Side effects of echinacea


Echinacea is an herb also known as Purple Cone Flower, Black Sampson, Black Susans, Fleur à Hérisson, Hedgehog, Igelkopfwurzel, Indian Head, Kansas Snakeroot, Red Sunflower, Rock-Up-Hat, Roter Sonnenhut, Rudbeckie Pourpre, Scurvy Root, Snakeroot, and many other names.

Echinacea has been used in alternative medicine as a possibly effective aid in treating the common cold, or vaginal yeast infections.

Echinacea has also been used to treat ear infections, or increasing exercise performance. However, research has shown that echinacea may not be effective in these conditions.

Other uses not proven with research have included treating anxiety, migraine headache, attention deficit hyperactivity disorder (ADHD), gingivitis, tonsillitis, genital herpes, human papilloma virus (HPV), low white blood cell counts, bladder infections, an eye condition called uveitis, and other conditions.

It is not certain whether echinacea is effective in treating any medical condition. Medicinal use of this product has not been approved by the FDA. Echinacea should not be used in place of medication prescribed for you by your doctor.

Echinacea is often sold as an herbal supplement. There are no regulated manufacturing standards in place for many herbal compounds and some marketed supplements have been found to be contaminated with toxic metals or other drugs. Herbal/health supplements should be purchased from a reliable source to minimize the risk of contamination.

Echinacea may also be used for purposes not listed in this product guide.

Follow all directions on the product label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

You should not use this product if you are allergic to echinacea or if you have:

  • an autoimmune disorder such as rheumatoid arthritis, lupus, or psoriasis.

Ask a doctor, pharmacist, or other healthcare provider if it is safe for you to use this product if you have any allergies, especially plant allergies (especially ragweed, mums, marigolds, or daisies).

It is not known whether echinacea will harm an unborn baby. Do not use this product without medical advice if you are pregnant.

It is not known whether echinacea passes into breast milk or if it could harm a nursing baby. Do not use this product without medical advice if you are breast-feeding a baby.

Do not give any herbal/health supplement to a child without medical advice. Echinacea should not be used in a child younger than 12 years old.

Echinacea and Golden Seal: The Dynamic Duo

Synthetic cold remedies from the druggist’s shelf do not look quite as good as they did a few years ago. The warning labels barely fit into the space available on the product box, and it is well-known to medical researchers that some ingredients in these products, such as aspirin, can cause stomach irritation—even bleeding. Further, research reports show that ingredients like aspirin and acetominophen have caused liver damage at therapeutic dosages.

What about antibiotics? Antibiotics don’t really touch viral infections, but are often prescribed to prevent complications like secondary bacterial infections. But what about the side effects of antibiotics, which include Immune suppression, allergic reactions, and mild liver damage. And doesn’t manufacturing synthetic drugs add to environmental pollution?

Echinacea is the purple Kansas cone-flower. It is a native American herb, from the plains states and grows to a lesser extent out to the east coast. The plant group Echinacea is made up of several different kinds or species, all occurring east of the Rocky mountains, though they are increasingly cultivated in Oregon and California. Two types of echinacea, Echinacea purpurea and Echinacea angustifolia, have been popular in American and European medicine for over 100 years. For centuries, they were considered the best remedies available, for rattlesnake bites, infections, and colds and flu, by the native American Indians. Pieces of echinacea root have been found in archeological digs from villages that were over 200 years old. Before synthetic medicine replaced most of the medicinal herbs prescribed by practitioners of “official” medicine, echinacea was included in one of America’s two official drug books—The National Formulary. It dropped out of sight for about 30 years (but not in Europe) and is now making a strong comeback.

Herbalists usually recommend the tea, powder, liquid extract or powdered extract for any kind of infection that is not deeply seated, or a result of a more serious weakness or deficiency. The extracts are preferred because they concentrate the active ingredients, which include important fat-soluble compounds such as polybutylamides and polyacetylenes and the water-soluble constituents cichoric acid and polysaccharides, which are giant sugar molecules. These well-researched active constituents have been shown to strongly stimulate various activities of immune function such as increased interferon activity which protects our cells against viral attack, and increased killer t-cell function, which can remove invading organisms. Echinacea can also stimulate the properdin/complement system, and the production of alpha-1 and alpha-2 gamma globulins, also helping to control and prevent infections.

In the old days, echinacea used to be called a “blood purifier.” Now we know that the immune constituents of echinacea stimulate our body’s phagocytes (cell-eaters) to engulf bacteria, virus-infected cells and wastes, recycling them and clearing them from the blood. This blood-purifying activity is important, because it can help prevent infections of bacterial, viral and fungal origin. This part of the immune system is the main focus area for echinacea , and I call it the “surface immune system”, or “protective shield,” because it affects the immune fighters in the mucous membranes throughout the body, especially in the upper respiratory tract, digestive tract and the urinary tract, where we are mainly exposed to outside organisms that may start an infection. This well-documented protective ability of echinacea, affecting several different mechanisms of our immune function, is a good reason why echinacea has become the herb of choice for such ailments as candida infections. Echinacea is also considered one of the most effective for infections such as strep throat, infected wounds, urinary tract infections, bronchitis, and of course, it is often the herb of choice for colds and flu. Modern science has shown it to have strong “surface immune” activating properties. In other words, it is very good at stimulating the “phagocytes”, or immune cells that protect us from virus and bacteria infections, by engulfing and recycling them. This part of our immune system I have called the “surface immune system,” or “protective shield.”

When we feel the first symptoms of a cold or flu, it is best to take a fairly strong dose, about 3 or 4 capsules of the powder, one dropperful of the liquid or one powdered extract capsule or tablet every 3 hours. In many cases, this “protective” measure may just forestall the impending cold or flu completely. I have seen it happen many times.

Golden seal is an eastern woodlands plant that likes to grow in rich soil. At one time it was abundant in Ohio, Missouri and Iowa to the Eastern seaboard, and all the way up into Canada. Today, because of its immense popularity, the wild resources are rapidly dwindling. This is true of echinacea as well. For this reason, I strongly recommend choosing commercial products of echinacea from “organically grown” sources. Look for organically-grown golden seal products as well.

Golden seal is a member of the buttercup family and has a bright yellow horizontal root or “rhizome” which is the part used in medicine. The plant was another favorite herb with the native people of America. According to early accounts from the diary of Lewis and Clark made on their trip to Oregon, Indian doctors used the root for infections and as a wash for any kind of eye irritation or infection. This use is still common today, and the root powder simmered in water and carefully filtered is still one of the best treatments for pink-eye and other similar ailments. Use golden seal powder from one “00” capsule in about 3 ounces of purified or distilled water.

Today, herbalists still widely recommend golden seal for many kinds of infections, inflammations and irritations of the mucous membranes. The mucous membranes are the “slime-producing” coating of our entire digestive tract, upper respiratory tract and urinary tract. They act as a protective barrier against bacteria, viruses and other kinds of mechanical irritation. When we have a urinary tract, upper respiratory tract or bowel inflammation or infection, it is mainly the mucous membranes which are first affected. Golden seal works well with these infections, bringing in more immune energy and increasing the micro-circulation to the “surface” (right beneath the membranes), which can help eliminate wastes and speed up the healing process. In Chinese medicine, golden seal is considered “cooling” because it lowers inflammation and removes heat.

Golden seal is also a good bitter tonic, and can help promote strong digestion and increase the production of enzymes and hydrochloric acid. However, it is important to note that some people can actually be harmed by golden seal, if they take it for too long a time or in too great a quantity—especially if they have weak digestion. I recommend two “00” capsules morning and evening around mealtimes for up to 10 days as a moderate dose.

So to summarise, golden seal is recommended for the following:

  • Sinus infections (sinusitis)
  • Mild bowel irritations and inflammations
  • Upper respiratory tract infections
  • Colds and flu
  • Hay fever
  • Urinary tract infections
  • Eye infections or irritations

It is best to take golden seal for limited periods (not more than 2 or 3 ten-day cycles every few months), and to add herbs such as cayenne or ginger if one’s digestion is weak or cold.

How do echincea and golden seal work together as the dynamic duo? During a cold, flu or infection, especially of the mucous membranes, echinacea can go to work to activate immune fighters, such as macrophages. These important defenders work to engulf and rid the body of virus-infected cells, bacteria, toxic wastes—helping to clear the debris of an “immune battle” from the site. The purple cone-flower can also help strengthen a protective gel that surrounds many of the body’s cells, thus keeping invading organisms from gaining a foothold. Golden seal, meanwhile, can help control the inflammatory process if it gets too carried away—if there is too much heat, redness, or swelling. The immune system can actually be inhibited in its protective job when this happens. It can also help bring more blood into the micro-circulation in the areas that are infected, such as the sinus cavities or urinary tract. It can help the body go through the infection much faster by bringing in more of the macrophages (that echinacea is activating) and helping to remove debris from the site.

© 1998 Christopher Hobbs

What is it and how does it work?
Echinacea is one of the top-selling herbal remedies throughout the world. It is also one of the oldest. Not only has this healing herb enjoyed long popularity, it also has been the subject of much scientific research. Echinacea is a native American plant that was recognized over a century ago as a natural infection fighter. It is an immunostimulant, a substance that boosts the body’s immune system. Unlike traditional antibiotics that kill bacteria directly, echinacea works indirectly, killing the germ by strengthening your immune system. While the entire echinacea story is still being researched, there is some evidence that it stimulates the body to produce more infection-fighting white blood cells, such as T-lymphocytes and killer white blood cells. It may also stimulate the release of interferons, one of the body’s most potent infection-fighting weapons. Interferon kills germs and also infiltrates their genetic control center, preventing them from reproducing. Besides helping the body produce more infection- fighting cells, echinacea helps these cells to produce more germ-eating cells, called macrophages, and it helps these cells eat the germs more voraciously, a process called phagocytosis. Echinacea also prevents bacteria from secreting an enzyme called hyaluronidase, which enables them to break through protective membranes, such as the lining of the intestines and respiratory tract, and invade tissues. Echinacea also seems to search out and destroy some viruses, such as the common cold and flu viruses. Here are some questions you may have about this valuable addition to your home pharmacy.

Is there proof that echinacea works?
Absolutely, but the research is not well known in America. The best research on echinacea comes from Germany, a country that is far ahead of the United States in the scientific study of over-the-counter herbal medicines. Echinacea has been studied in Germany using double-blind, placebo-controlled studies, the gold standard for scientific research on drugs. In this type of study, one group gets the real pill and the other group, the control group, gets a look-alike dummy pill. Neither the researcher nor the research subjects know who has gotten which pill until data collection is completed and the data are analyzed. This kind of research is especially necessary in studying herbal medicines to correct for the well-known placebo effect in which even a dummy pill can produce healing effects because of the power of suggestion. A double- blind, placebo-controlled study has shown that echinacea users experienced less frequent and less severe virus infections (colds and flus) by one-third to one-half compared to the group that took dummy pills (which interestingly also reported a decrease in severity of flu symptoms).

Is echinacea safe?
Studies have not shown any toxic effects of echinacea. The occasional person may experience some G.I. disturbances, such as diarrhea.

How should echinacea be taken and what is the proper dosage?
When and how much echinacea to take depends on your individual immune system and the medical reason why you want to take it. Best to seek dosage and timing advice from a naturopath or medical doctor knowledgeable about herbal medicines. For example, there are conditions in which you wouldn’t want to hype up your immune system, such as illnesses presumably caused by an overactive immune system called “autoimmune diseases.”

Studies on the safety and efficacy of echinacea in adults suggest the following dosage:

  • 300 milligrams three time a day for a total of 900 milligrams a day.
  • The dosage in children has not been studied as much, but a sensible amount would be one- half the adult dose for children ages six to thirteen, and one-quarter the adult dose for children under six.

Some people take echinacea all the time to prevent colds and flu, and others take it just for a couple of weeks when they feel the first signs of a cold coming on or if they have been exposed to a contagious viral infection. While there is no scientific evidence that taking echinacea daily for months is harmful, theoretically, taking any immune booster for too long could cause it to lose its punch or could stress the immune system. Another theoretical concern is that any drug that tampers with the genetic material of a virus cell (as echinacea does) could also affect the genetic material of cells in the body or could cause viruses to change genetically and become more resistant and more virulent.

Because of these concerns, taking echinacea as a preventive medicine during the cold and flu season (two weeks on / two weeks off) may be unwise, as there is no scientific basis for this popular regimen. Instead consider the following:

  1. When you feel a cold coming on or have been exposed to a contagious virus, take echinacea for two weeks, then stop.
  2. When you are under stress because of life changes (positive as well as negative)–pressures at work or at home, travel, or any other situation that affects your emotional or physical health– take echinacea for a couple of weeks.
  3. When entering a situation that challenges the immune system, such as the beginning of school in September, entering a new daycare situation, or exposure to any other new group of people that increases your contact with germs, take echinacea for two weeks.

Feeding your immune system each day is one way to help your medical bills go away.

August 9, 2013 August 9, 2013 Dr. Bill Sears

Echinacea: Benefits, Uses, Side Effects and Dosage

Research on echinacea suggests that it offers several impressive health benefits.

Positive Effect on the Immune System

Echinacea is best known for its beneficial effects on the immune system.

Numerous studies have found that this plant may help your immune system combat infections and viruses, which could help you recover faster from illness (8, 9, 10).

That’s one reason why echinacea is often used to prevent or treat the common cold.

In fact, a review of 14 studies found that taking echinacea may lower the risk of developing colds by more than 50% and shorten the duration of colds by one and a half days (11).

However, many studies on this topic are poorly designed and show no real benefit. This makes it hard to know if any benefits on colds are from taking echinacea or simply from chance (12).

In short, while echinacea may boost immunity, its effects on the common cold are unclear.

May Lower Blood Sugar Levels

High blood sugar can raise your risk of serious health problems.

This includes type 2 diabetes, heart disease and several other chronic conditions.

Test-tube studies have found that echinacea plants may help lower blood sugar levels.

In a test-tube study, an Echinacea purpurea extract was shown to suppress enzymes that digest carbohydrates. This would reduce the amount of sugar entering your blood if consumed (13).

Other test-tube studies found that echinacea extracts made cells more sensitive to insulin’s effects by activating the PPAR-y receptor, a common target of diabetes drugs (14, 15).

This particular receptor works by removing excess fat in the blood, which is a risk factor for insulin resistance. This makes it easier for cells to respond to insulin and sugar (16).

Still, human-based research on the effects of echinacea on blood sugar is lacking.

May Reduce Feelings of Anxiety

Anxiety is a common problem that affects close to one in five American adults (17).

In recent years, echinacea plants have emerged as a potential aid for anxiety.

Research has discovered that echinacea plants contain compounds that may reduce feelings of anxiety. These include alkamides, rosmarinic acid and caffeic acid (18).

In one mouse study, three out of five echinacea samples helped reduce anxiety. In addition, they did not make the mice less active, in contrast to higher doses of standard treatments (18).

Another study found that Echinacea angustifolia extract rapidly reduced feelings of anxiety in both mice and humans (19).

However, as of now, only a handful of studies on echinacea and anxiety exist. More research is needed before echinacea products can be recommended as a possible treatment.

Anti-Inflammatory Properties

Inflammation is your body’s natural way of promoting healing and defending itself.

Sometimes inflammation can get out of hand and last for longer than necessary and expected. This may raise your risk of chronic diseases and other health problems.

Several studies have shown that echinacea can help reduce excess inflammation.

In a mouse study, echinacea compounds helped reduce important inflammatory markers and memory-loss caused by inflammation (20).

In another 30-day study, adults with osteoarthritis found that taking a supplement containing echinacea extract significantly reduced inflammation, chronic pain and swelling.

Interestingly, these adults did not respond well to conventional non-steroidal inflammatory drugs (NSAIDS) but found the supplement containing echinacea extract helpful (21).

May Help Treat Skin Concerns

Research has shown that echinacea plants may help treat common skin concerns.

In a test-tube study, scientists found that echinacea’s anti-inflammatory and anti-bacterial properties suppressed the growth of Propionibacterium, a common cause of acne (22).

In another study in 10 healthy people aged 25–40, skin care products containing echinacea extract were found to improve skin hydration and reduce wrinkles (23).

Similarly, a cream containing Echinacea purpurea extract was shown to improve eczema symptoms and help repair the skin’s thin, protective outer layer (24).

However, echinacea extract appears to have a short shelf life, making it difficult to incorporate into commercial skin care products.

May Offer Protection Against Cancer

Cancer is a disease that involves the uncontrolled growth of cells.

Test-tube studies have shown that echinacea extracts may suppress cancer cell growth and even trigger cancer cell death (25, 26).

In one test-tube study, an extract of Echinacea purpurea and chicoric acid (naturally found in echinacea plants) was shown to trigger cancer cell death (25).

In another test-tube study, extracts from echinacea plants (Echinacea purpurea, Echinacea angustifolia and Echinacea pallida) killed human cancer cells from the pancreas and colon by stimulating a process called apoptosis or controlled cell death (26).

It’s believed that this effect occurs due to echinacea’s immune-boosting properties (27).

There was some concern that echinacea could interact with conventional cancer treatments, such as doxorubicin, but newer studies have found no interaction (28, 29).

That being said, human studies are needed before making any recommendations.

Summary Echinacea has been shown to improve immunity, blood sugar, anxiety, inflammation and skin health. It may even have anti-cancer properties. However, human-based research on these benefits is often limited.

General cancer information

Echinacea is a herb that grows wild in parts of North America. In Europe people use it as a herbal supplement.


  • Echinacea is a herb that grows in North America
  • There is no scientific evidence to support its use as a cancer treatment
  • Echinacea might have side effects

What is echinacea?

Echinacea is a wild herb. It grows in the Great Plains and eastern parts of North America. It is also grown in Europe .

Common names for echinacea include:

  • coneflower, purple coneflower or American coneflower
  • Kansas snakeroot
  • black sampson or sampson root

There are different varieties including:

  • echinacea purpurea
  • echinacea angustifolia
  • echinacea pallida

Manufacturers make a liquid extract from the leaves, roots or the whole plant .

Echinacea is mostly available as the herbal remedy echinacea purpurea. Some preparations do not say which variety they contain.

There is no scientific evidence to use it as a treatment for cancer in humans.

Manufacturers of echinacea promote it as a supplement. They say it can prevent and lessen the symptoms of the common cold, flu and infections of the airways. It might also work as an antiseptic and help wounds to heal.

Why people with cancer use it

A survey in America looked into complementary and alternative medicine use in adults. They found that echinacea was the most commonly used natural product.

There is no evidence that echinacea can help with cancer. But some people take it because they believe it might:

  • boost their immune system
  • fight their cancer
  • give them some control over their cancer and its treatment
  • treat their cancer if conventional treatment can no longer offer a possible cure

Laboratory and animal studies of echinacea have shown that it stimulated immune cells. It also prevented inflammation. But there are no clinical trial results to show this in humans. Studies in humans only showed changes to the immune system.

There is continuing research into its use to fight infections, viruses and cancer. In laboratory studies on human colon cancer cells echinacea caused cell death. But this is not enough evidence to use it as a treatment for cancer.

In some studies researchers found that echinacea could cause chemotherapy to work less well. And it could cause side effects.

How you have it

Echinacea comes as:

  • capsules
  • a liquid to dilute and drink
  • an ointment
  • injections in some European countries (not available in the USA)

You can buy many echinacea products from:

  • health food stores
  • chemists
  • over the internet

Dosages may vary because of different species in tinctures, tablets and liquids. So there is no standard dose.

Some herbalists say you shouldn’t take echinacea for longer than 8 weeks. This is due to possible side effects. But a study in Cardiff in 2012 seemed to show that it is safe to take for up to 4 months.

You can also buy echinacea ointment to help heal skin wounds. Echinacea injections are available in some European countries but not in America.

In Europe, only buy registered products under the Traditional Herbal Remedies (THR) scheme. Registered remedies under the scheme have a THR mark and symbol on the packaging. THR products have had tests for quality and safety.

Side effects

Echinacea is generally safe to take, and severe side effects seem rare.

The more common side effects of echinacea include:

  • headaches
  • dizziness
  • feeling sick
  • stomach ache
  • constipation
  • skin reactions (redness, itchiness and swelling) – these are more common in children

Using echinacea for longer than 8 weeks at a time might damage your liver or suppress your immune system. Herbalists recommend not to take echinacea if you are taking medicines known to affect your liver.

Check with your doctor first if you are having any other drugs, herbs, or supplements.

There is also a rare chance of a serious allergic reaction to echinacea.

Using echinacea safely

Tell your doctor if you want to replace your cancer treatment with echinacea. Also, if you are thinking of taking it alongside your cancer treatment.

It might be safe to use alongside your other cancer treatment but in some people, it is not.

Echinacea might interfere with how certain chemotherapy drugs, such as etoposide, work.

Pharmacists and doctors sometimes recommend people with lymphoma not to take echinacea. This is because it could interfere with their treatment.

In people with HIV, researchers found that it was safe to take echinacea with the drug etravine.

Talk to your doctor before taking echinacea if you:

  • are pregnant or breastfeeding
  • have a medical condition that affects your immune system, such as an autoimmune disease, HIV or AIDS
  • are taking drugs to suppress your immune system, because it may work against them
  • are under the age of 12 – the medical health regulatory association (MHRA) says there is a risk of allergic reactions such as skin rashes

Always ask your doctors and nurses about using complementary or alternative cancer therapies. They might interact with your other treatments.

If your treatment team don’t have the information you need they can direct you to other people who can help.

Research into echinacea

Some laboratory research says echinacea can boost different types of immune cells. It also says that it can decrease inflammation and kill bacteria and viruses. But human trials haven’t been able to prove this.

There is no scientific evidence to show that echinacea can help treat, prevent or cure cancer in any way.

There are claims that echinacea can relieve side effects from chemotherapy and radiotherapy. But there is no proof of this.

Doing clinical trials using herbal treatments is often difficult. Challenges researchers face include:

  • finding the best dose
  • finding out which part of the plant to use, for example the stem, flowers, leaves or root
  • looking at the differences between the different varieties of the herb

Researchers are looking into the benefits of echinacea in fighting infections and viruses.

In 2014 researchers used echinacea in a pilot study on 10 healthy people. A pilot study is a small-scale version of the main study. Pilot studies help to test that all the main parts of the study work together.

The researchers found that echinacea had some effect on the immune system. But this was only a small study. We need more research.

Researchers published a Cochrane Library systematic review in 2006. A systematic review means that a group of experts gather all the evidence about a particular subject. They then go through it to work out whether there is any evidence to support it. In the review researchers looked at 13 trials. The trials looked at whether using echinacea might treat and prevent the common cold.

Some of the studies showed that it might reduce the length of time colds last and relieve symptoms. But others showed that it did not work.

The review found that there was no evidence that echinacea could prevent the common cold. They recommended more research into how echinacea could help to treat infections. Also, to learn more about its side effects.

A study in 2010 looked at how well echinacea root worked for people who already had colds. It found that taking echinacea did not make any difference to how long the colds lasted.

In 2012 researchers did a study on more than 700 people. They found that people who took echinacea every day for at least 4 months had fewer colds and few side effects.

Researchers did another Cochrane review in 2014. They found that echinacea products on the market differ widely.

They also found that some types might reduce the risk of getting a cold in between 10 to 20 out of every 100 people (10% to 20%).

The researchers felt that this was a small effect and that the evidence to support it was unclear. This is because the studies used different preparations of echinacea.

In 2013 researchers looked at echinacea angustifolia. It is a variety of echinacea and is used as a treatment for anxiety. They found that all the people in the study who took echinacea felt less anxious after 2 days. They remained so for the 7 days of the study. The effect lasted for 2 weeks after the study.

In 2018 researchers in the USA started another study on echinacea angustifolia. The study is also looking at echinacea as a treatment for anxiety. They want to see if it is a safe and an effective treatment for generalised anxiety disorder (GAD) symptoms.

How much it costs

Echinacea is sold in health food shops, chemists and over the internet. The price can vary depending on:

  • the dose
  • the amount you buy
  • where you buy it (health food shops, chemist or online)

A word of caution

It is understandable that you might want to try anything if you think it might help treat or cure your cancer. Only you can decide whether to use a complementary cancer therapy such as echinacea.

You could harm your health if you stop your cancer treatment for an unproven treatment.

Many websites might promote echinacea as a cure for cancer. But no reputable scientific cancer organisations support any of these claims. Be cautious about believing this type of information or paying for any complementary cancer therapy over the internet.

Useful organisations

You can get more information about echinacea from the following organisations.

The National Institute for Medical Herbalists

Clover House
James Court
South Street

Phone: 01392 426022
Email: [email protected]

The College of Practitioners of Phytotherapy

Oak Glade
9 Hythe Close
East Sussex
BN26 6LQ

Phone: 01323 484353
Email: [email protected]


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Echinacea is a widely used herbal supplement that is taken to boost the immune system. IT is one of the more promising traditional remedies for the common cold, and it has other potential applications in skin health and anxiety. Read on to learn about all the ways echinacea might improve your health.

What is Echinacea?

Echinacea is a group of plant species. There are 9 species belonging to the echinacea subfamily. Extracts from these species have largely been used in traditional medicine to treat blood poisoning, bacterial infections, and the common cold .


Although they belong to the same subfamily, each species of echinacea has a particular set of molecules with biological activity. Different growing conditions, time of harvest, drying, and storage conditions also change the quantity of the active compounds in each plant .

Some of the active compounds in echinacea include:

  • Alkamides (alkylamides)
  • Glycoproteins and polysaccharides
  • Caffeic acid derivatives (phenylpropanoids)
  • Volatile oils
  • Others: Alkaloids, flavonoids (quercetin, kaempferol, isorhamnetin, patuletin-3-rutinoside), anthocyanins, phenolic acids (p-coumaric, p-hydroxybenzoic, and protocatechuic acids) .

Mechanism of Action

Echinacea has various effects on the immune system. The mechanism of action in humans is not completely understood.

Antioxidant Activity

Echinacea extracts have antioxidant activity; they scavenge free radicals (hydroxyl and DPPH radicals) and also inhibit cell damage (lipid peroxidation) caused by oxidative stress .

In mice injected with echinacea for 3 weeks, the antioxidant activity (SOD) of blood was increased .

Dendritic Cell Activity

Antigen-presenting cells are white blood cells that contribute to the immune system by recognizing foreign molecules. Dendritic cells are one such type of cell, and they require activation to function. After they are activated, they can produce pro and anti-inflammatory molecules called cytokines.

In cell studies, echinacea improved dendritic cell function by :

  • Increasing activation of dendritic cells
  • Increasing release of immune molecules (IL-8, IL-1beta and IL-18)
  • Increasing antioxidants
  • Increasing proteins that support cell structure

Root extracts were more effective in activating dendritic cells than leaf extracts .

Macrophage Activity

Macrophages are a type of white blood cell. They “eat” (phagocytose) foreign substances and dead cells in our blood. When activated in response to inflammatory signals or bacteria, they release inflammatory molecules called cytokines .

Some inflammatory molecules released by macrophages can activate natural killer cells (NK cells). Natural killer cells can then clear the infection from the body or recruit other white blood cells that assist in eliminating infections.

In cell studies, echinacea influenced macrophage activity in different ways :

  • It increased the production of specific molecules (IL-2 and IFN-gamma) that activate macrophages and natural killer cells.
  • During bacterial infection, it reduced inflammation (TNF-alpha and IL-1beta). This reduces the symptoms and irritation caused by inflammation but does not address the cause infection.

Two types of active components of echinacea, alkamides and polysaccharides, may have specific effects on macrophages.

Alkamides :

  • May improve the activity of macrophages in healthy lungs. This is mediated by their activity at the macrophage cannabinoid receptors (CB2), resulting in the production of inflammatory molecules (TNF-alpha and NO).
  • Deactivate macrophages when exposed to bacteria. This could potentially reduce inflammation, but some studies have shown increases in inflammatory molecules (TNF-alpha and NO).

Polysaccharides :

  • May increase the activation of natural killer cells. This may be caused by their ability to increase the production of inflammatory molecules (IL-1, TNF-alpha, and IL-6).
  • May also increase the production of reactive oxygen species (ROS) by macrophages, aiding in the destruction of bacteria.
  • May reduce inflammation during viral (influenza) infection (IL-10 and IFN-gamma).

Antimicrobial Activity

Alkamide molecules found in echinacea extracts disrupt the fungal cell wall .

Echinacea has antiviral activity against viruses that have membranes. These include:

  • Rhinovirus
  • Herpes simplex
  • Influenza A and B
  • Coronavirus
  • Respiratory syncytial virus

In dog cells infected with the influenza viruses, echinacea treatment prevented the virus from entering the cell by blocking viral receptors (hemagglutinin and neuraminidase) .

Other Mechanisms

Alkamides from echinacea extracts inhibit the enzymes cyclooxygenases 1 and 2 .

Alkamides activate PPAR-gamma in fat cells without increasing the amount of fat. Activating PPAR-gamma increases the action of insulin by promoting the storage of glucose in fat cells .

Echinacea inhibits the enzyme hyaluronidase. Hyaluronidase is responsible for breaking down hyaluronic acid in the skin, which is an important component of skin cells. When broken down, the tissue loosens up and causes inflammation. Inhibiting the breakdown of hyaluronic acid reduces inflammation and promotes skin healing .

Health Benefits of Echinacea

Echinacea is considered very safe, but supplements have not been approved by the FDA for medical use and generally lack solid clinical research. Regulations set manufacturing standards for them but don’t guarantee that they’re safe or effective. Speak with your doctor before supplementing.

Possibly Effective

1) Common Cold

Echinacea is perhaps best-known as a traditional remedy for the common cold.

In a study of 282 patients, echinacea taken at the first symptom of a cold reduced the severity of the symptoms .

Different clinical trials on the use of echinacea indicate that echinacea may either help or have no effect on the treatment of colds .

A meta-analysis found that echinacea extracts prevented colds and shortened their duration by an average of 1.4 days .

When studying the effects of rhinovirus colds in humans, which is the most common virus responsible for colds, echinacea helped prevent the symptoms of the common cold .

A different meta-analysis found some extracts have no clinically relevant effect in the prevention of colds .

The positive effects of echinacea extracts on cold symptoms likely derive from its anti-inflammatory activity on the airway .

Insufficient Evidence For

The following purported benefits are only supported by limited, low-quality clinical studies. There is insufficient evidence to support the use of echinacea for any of the below-listed uses. Remember to speak with a doctor before taking echinacea supplements, and never use them in place of something your doctor recommends or prescribes.

2) Immunity

In a study of 6 adults treated for 3 days, echinacea extract reduced inflammation and increased the production of molecules (IFN-alpha) that fight infection .

Echinacea is believed to promote overall immune function and reduce inflammation .

Echinacea extract increases the number of circulating white blood cells (lymphocytes and monocytes) in mice and rats .

Echinacea inhibited inflammatory molecules (IL- 6, IL-8) after viral infection in lung cells. In a model of the human airway, treatment with echinacea reduced mucus in the lungs (reduction in mucopolysaccharide and mucin) .

In mouse white blood cells, echinacea affected antibody (immunoglobulin) production in contradictory ways. Although some studies indicated that antibodies are increased, others have reported that echinacea has no effect or can even decrease antibodies .

3) Skin Health

In 49 patients, treatment with echinacea for 3 months helped improve the symptoms of atopic dermatitis (redness and swelling) .

In cells, echinacea inhibited collagen breakdown by free radicals. It also aided in wound healing (cicatrizing) after topical application in rats. This is attributed to its antioxidant activity and ability to reduce skin irritation (inhibition of hyaluronidase) .

Echinacea can aid in the treatment of acne by inhibiting the growth of the bacteria P. acnes and limiting inflammation .

4) Anxiety

Echinacea reduced mild anxiety in 32 healthy adults taking echinacea for 7 days .

In rats, echinacea reduced anxiety-like behaviors .

This might result from the ability of echinacea to bind to the CB2 cannabinoid receptor .

Animal & Cell Studies (Lacking Evidence)

No clinical evidence supports the use of echinacea for any of the conditions listed in this section. Below is a summary of the existing animal and cell-based research, which should guide further investigational efforts. However, the studies listed below should not be interpreted as supportive of any health benefit.

5) Inflammation

Echinacea extracts had an anti-inflammatory effect in rats after both topical and oral use .

Echinacea extract decreased airway inflammation and expanded air passages in guinea pigs, having an effect similar to salbutamol .

Echinacea decreases inflammation through the inhibition of pro-inflammatory molecules and by binding to the cannabinoid receptor (see Mechanism for more details). This does not necessarily help fight infections but can help reduce the symptoms of infection.

These effects might also result from the ability of echinacea to inhibit cyclooxygenase, an enzyme that helps in the formation of inflammatory molecules (prostaglandins, thromboxane, and levuloglandins). Cyclooxygenase is the target of many non-steroidal anti-inflammatory drugs (NSAIDs), such as aspirin and ibuprofen .

6) Antimicrobial Activity


In multiple cell studies, echinacea had antiviral activity against herpes simplex, rhinoviruses, human, avian, and swine influenza viruses. Echinacea is not effective against viruses once they have entered the cell .

In dog kidney cells, echinacea extract also prevented the influenza A virus from binding to cells, preventing the virus from entering .

Echinacea extract decreased the severity of influenza infection in mice .

Echinacea displayed its effects mainly in viruses with membranes (such as herpes simplex, influenza, and coronaviruses), probably through its ability to interact with membranes and block hemagglutinin and neuraminidase receptors.


Echinacea inhibited the growth of yeast (Candida albicans) .

In mice, echinacea treatment protected against lethal infections with different species (C. albicans and Listeria monocytogenes) .

This effect might be derived from the ability of echinacea to damage the fungal cell wall .

Bacteria and Parasites

Echinacea has antibacterial activity against S. pyogenes, H. influenzae, L. pneumophila, C. difficile, and P. acne .

In human cells, echinacea also kills parasites L. donovani, L. major, and T. brucei .

7) Diabetes

Obesity can increase insulin resistance, resulting in lower amounts of glucose entering the cells and higher glucose levels in the blood. Over time this can lead to type 2 diabetes .

Echinacea extracts increased the activity of insulin in mouse fat cells, resulting in increased glucose uptake. This is caused by the activation of PPAR-gamma. Therefore, echinacea might be useful for the treatment of insulin resistance related to obesity or type 2 diabetes .

8) Pain

Echinacea extract inhibits the TRPV1 receptor, a receptor that influences our perception of pain and reduces inflammation. It also inhibits cyclooxygenase enzymes, which are the target of many non-steroidal anti-inflammatory drugs (NSAIDs) that relieve pain .

9) Depression

Echinacea extract had antidepressant effects in rats and increased the stimulating effects of L-DOPA (an amino acid that is transformed into dopamine) .

Cancer Research

Echinacea inhibits the growth of cancerous colon and pancreas cells .

Echinacea also prevented the death of normal cells that were treated with chemotherapy, resulting in the death of only cancerous cells .

However, many substances have anti-cancer effects in cells, including downright toxic chemicals like bleach. This doesn’t mean that they have any medical value. On the contrary, most substances (natural or synthetic) that are researched in cancer cells fail to pass further animal studies or clinical trials due to a lack of safety or efficacy.

Natural Sources

Three species of echinacea are generally used for human consumption:

  • Echinacea purpurea
  • Echinacea angustifolia
  • Echinacea pallida

The roots of the 3 species are used, either fresh or dried. Typically, the flowers, leaves, and stems of E. purpurea are used too .

Commercially available products can be found in different formulations:

  • Dried roots
  • Dried leaves
  • Tinctures (extract in alcohol)
  • Water-based extracts
  • Tablets
  • Teas
  • Capsules
  • Freshly pressed into a juice

They might include the whole plant, only roots or the flowers, leaves, and stems.

Depending on the extraction conditions and part of the plant used, the active chemicals can vary amongst different echinacea formulations .

Side Effects & Precautions

According to data from clinical trials, side effects from echinacea consumption are rare. The common adverse reactions seen include rash and mild stomach problems such as nausea and stomach aches .

Allergic reactions may occur, especially in people allergic to other plants of the same family (such as chamomile) .


Due to the effects of echinacea on immune function, people with autoimmune or systemic diseases like tuberculosis, multiple sclerosis, or AIDS should not use echinacea. This also applies to patients taking immunosuppressants .


In studies with women that used echinacea during pregnancy, no negative effects were found. However, excessive use of echinacea during pregnancy and breastfeeding is not recommended .


The use of echinacea was found to be safe for children (ages 2-12) for up to 10 days .

To avoid adverse effects or unexpected interactions, talk to your doctor before using significant quantities of echinacea. If you experience an allergic reaction or serious side effects, seek medical attention immediately.

Limitations and Caveats

Despite the multiple biological activities of echinacea, many of the benefits have not yet been proven in humans.

The overall effects of echinacea on humans are difficult to establish since the clinical trials conducted have used different kinds of echinacea extracts. Some clinical trials have found no effects of echinacea on immune function and or the treatment of colds .

The concentration of biologically active compounds in echinacea varies between species and even between individual plants .

Alkamides from echinacea extracts are biologically available, meaning that they enter the bloodstream and can act internally. Other chemical compounds found in echinacea (caffeic acid derivatives, polysaccharides) have not been studied for their biological availability and it is not known if they reach the blood after oral uptake .

Modern echinacea supplements are composed of multiple echinacea species. The composition of these supplements can vary depending on which species were used and which parts of the plant were included (stem, flower, extracts). Therefore, echinacea supplements purchased from different sources can have varying health outcomes for the body.

Drug Interactions and Genetic Variations

Echinacea affects the activity of enzymes responsible for breaking down drugs and potentially toxic compounds. These include:

  • CYP2C9: Weakly inhibited
  • CYP1A2: Inhibited
  • CYP3A4 (intestinal): Inhibited
  • CYP3A4 (liver): Promoted

This could induce toxic blood concentrations of certain drugs such as (S)-warfarin and theophylline. It could also increase the availability of drugs that are broken down by the enzyme CYP3A4 such as verapamil, cyclosporine, and tacrolimus .

Why do people take echinacea?

Many people take echinacea in the hopes that it will boost immunity. Studies have had mixed results.

So far, evidence suggests that echinacea may prevent the common cold. It also might help as a treatment. Some studies, many of them small, have found that taking echinacea may reduce the length of a cold and the severity of its symptoms. However, two large clinical trials found no benefits at all.

It’s important to note that there are different species of echinacea, such as Echinacea purpurea, Echinacea pallida, and Echinacea angustifolia. Some of the conflicting findings may result from researchers testing different varieties. The strongest evidence for echinacea as a cold treatment comes from studies of Echinacea purpurea. Studies of Echinacea angustifolia and any echinacea root have had weaker results. Echinacea may not work as well in children and young adults as it does in older adults.

When taken along with an antifungal cream, oral echinacea may help prevent recurrent vaginal yeast infections. While some studies suggest that echinacea may slightly reduce flu symptoms, the evidence isn’t clear.

Echinacea does not seem to help prevent or treat herpes. The effect of echinacea on other conditions is not known.

It’s the season when many of us will come down with the common cold. And if you have kids in school, chances are you’ll get hit more than once.

With the inevitable misery of cold season, many Canadians stock up on natural remedies to help relieve sore, scratchy throats, sneezing and runny noses.

One popular cold fighter is echinacea, an herbal remedy believed to boost the body’s immune system and lessen the duration and severity of cold symptoms.

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But according to a study published Tuesday in the Annals of Internal Medicine, it’s a supplement that offers little relief.

Previous studies – several hundred in fact – have tested echinacea for preventing or treating colds with mixed results.

In the current study, researchers from the University of Wisconsin studied 719 people, aged 12 to 80, with early cold symptoms. Participants were assigned to receive either no pill, echinacea, or a placebo. Patients then recorded their symptoms twice a day for one week.

Compared to folks given no pills or placebos, those taking Echinacea had only a slight decrease in the duration of their colds. Echinacea users experienced, on average, a 10 per cent reduction (seven to 10 hours) in the duration of theirweek-long cold, a finding that wasn’t deemed statistically significant (e.g. it could have happened by chance).

As well, there was no significant decrease in the severity of cold symptoms between echinacea users and non-users.

In truth, there’s very little you can do to fight the common cold because we have no way to attack the 200-plus viruses that cause colds.

That said, there’s growing evidence that some natural health products can offer cold relief, at least to a modest degree. Studies suggest the following alternative treatments might take the edge off your cold.

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(Before taking any herb or supplement, speak to your doctor if you are pregnant, have a medical condition, or take medication that may interact with certain supplements.)

Vitamin C

Data does not support the notion that taking vitamin C will prevent you from catching a cold, but as a treatment, the evidence is much better. Most studies show that vitamin C can decrease the duration of a cold by 24 to 36 hours.

To reduce cold symptoms, take 2,000 milligrams of vitamin C a day, in divided doses (e.g. 500 milligrams four times a day). The supplement appears to be most effective in children, people under physical stress and those with low dietary intakes of vitamin C.

Taking high doses of vitamin C for prolonged periods may increase the risk of kidney stones. People with a history of kidney stones should restrict their intake to 100 milligrams a day.


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Zinc lozenges are a popular treatment for colds and most studies suggest they do ease symptoms and speed up recovery in adults. It’s believed that zinc may block the replication of cold viruses.

Lozenges of zinc gluconate or zinc acetate should be taken every two hours while awake, starting within the first 48 hours of symptoms. Most zinc lozenges contain 10 milligrams of zinc. Do not take more than 50 milligrams (5 lozenges) of zinc a day; too much zinc can depress immune function.


Clinical studies have found this special extract of North American ginseng, made by Afexa Life Sciences Inc., is effective at reducing the frequency, severity and duration of colds in healthy adults and seniors by boosting the immune system.

The recommended dose of Cold-FX is 200 milligrams, twice daily, during cold and flu season. Cold-FX Extra Strength is a higher dose to be used short-term at the first sign of cold symptoms.


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These friendly strains of bacteria added to yogurt and sold as supplements are thought to stimulate the immune system. In adults and children, taking a daily supplement containing lactobacilli and bifidobacteria has been shown to reduce the severity and duration of colds.

To supplement, buy a product that contains 1 billion to 10 billion live cells per dose (capsule). Choose a probiotic supplement that contains both lactobacilli and bifidobacteria strains. Children’s products are available on the market; these usually contain one-quarter to one-half of the adult dose.


This herb appears to boost the immune system and fight viruses. Some research, although preliminary, even suggests that garlic can help prevent you from catching a cold.

Raw garlic – crushed or minced – seems to work better that cooked garlic. Keep in mind that raw garlic can cause stomach upset and may increase the risk of bleeding in people taking blood thinning medications.

Leslie Beck, a Toronto-based dietitian at the Medcan Clinic, is on CTV’s Canada AM every Wednesday. Her website is

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