Antibiotics that cause diarrhea

Antibiotic-Associated Diarrhea

What Is It?

Published: February, 2019

In healthy people, many different species of bacteria live inside the bowel. Many are harmless or even helpful to the body, but a few have the potential to be aggressive troublemakers. Under normal circumstances, the “bad” bacteria are far outnumbered. So, the bowel’s natural ecological balance keeps them under control.

This can change dramatically when a person begins treatment with an antibiotic. This is because antibiotics can kill large numbers of the bowel’s normal bacteria, altering the delicate balance among the various species.

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Eating yogurt or taking a so-called probiotic when you have to take antibiotics may help prevent the diarrhea that often accompanies antibiotic treatment.

That’s the conclusion of a study just published in the Journal of the American Medical Association. A team of California-based researchers combined the results of 63 randomized trials pitting probiotics versus placebo among almost 12,000 men and women taking antibiotics. Those who took antibiotics plus probiotics were 42% less likely to develop diarrhea as those who got the placebo.

About one in three people who take antibiotics develop diarrhea. The symptoms usually start on the last day or two of antibiotic therapy, or a day or so after it has ended. The diarrhea is usually mild, with two to four loose stools per a lasting for a couple days. In most cases, it gets better quickly without treatment. That said, antibiotic-associated diarrhea makes some people very sick. The most severe form, called C. difficile colitis, can be life threatening.

Probiotics are live bacteria, yeast, and other microbes thought to be beneficial to human health. They’ve been widely promoted as a way to keep your body in balance. The evidence for many of these claims is slim. Perhaps the strongest evidence a benefit of probiotics is for antibiotic-associated diarrhea.

Antibiotics upset intestinal balance

Thousands of species of bacteria, yeast, and other microorganisms live on our skin, in our intestines, and on other body surfaces. They’re known as our “normal flora.” When it is in balance, these microbes stay put and many of them contribute to good health. Bacteria in the gut, for example, help break down food.

Antibiotics kill these “good” microbes along with bacteria that are causing an infection. This upsets the balance of the normal flora in the intestines. The result is often loose, watery stools known as antibiotic-associated diarrhea.

The idea behind using probiotics is that they may help populations of good bacteria recover more quickly and restore order to the intestines. There’s no good evidence that probiotics are helpful in otherwise healthy people. But earlier research has suggested they can be helpful in:

  • treating recurrent or persistent C. difficile colitis, when repeated courses of other therapies have not been successful
  • preventing complications from pancreatitis
  • decreasing persistent or recurring vaginal yeast infections

Not a cure-all

Although the results of this study sound impressive, I won’t be recommending probiotics every time I write a prescription for antibiotic. But I will advise some of my patients to try a probiotic. They include:

  • people who have had antibiotic-associated diarrhea in the past. This is especially true for those that have had a C. difficile infection.
  • people who must take antibiotics for more than 10 days. (Other doctors might use more than 5 days).
  • people who have switched from one antibiotic to another over a relatively short period of time.

The researchers were not able to answer two very important questions:

  • Which probiotics are the most effective in preventing and treating antibiotic associated diarrhea?
  • Which antibiotics are more likely to cause diarrhea?

The medical bottom line

Antibiotics are wonderful medicines. But this study of probiotics and many other studies show they also have a dark side. The best way to avoid antibiotic-associated diarrhea is to limit your use of antibiotics. For example, you likely don’t need an antibiotic for an uncomplicated ear or sinus infection or bronchitis. Most often the culprits are viruses, which don’t respond to antibiotics anyway.

The best way to keep your normal flora in balance is to only take antibiotics when necessary.

How to Keep Antibiotics From Causing Diarrhea

Protect Yourself

Some patients find they can take certain antibiotics and diarrhea won’t be a problem, but taking other drugs will cause diarrhea, Parkman says. If you have diarrhea from taking antibiotics, especially if symptoms persist or worsen, call your doctor. If it’s necessary for you to continue antibiotics treatment, your doctor may be able to switch you to another drug that won’t have this side effect.

If you’re taking an antibiotic, consider changing your diet for a few days to avoid foods that commonly trigger diarrhea, such as dairy products, fatty foods, spicy foods, and foods high in fiber like whole-grain breads, cereals, and beans. You should also sip water and skip caffeine and alcohol. If your symptoms of antibiotic-associated diarrhea are severe, your doctor may recommend bed rest, intravenous fluids to replace your electrolytes — sodium, potassium, and chloride — and another antibiotic to treat the bad intestinal bacteria that is causing diarrhea.

Probiotics May Relieve Diarrhea

Probiotics are friendly bacteria or yeast that help your digestive system function properly. A growing body of research shows that probiotics may help protect against antibiotic-associated diarrhea. In particular, some people have found that the probiotic Lactobacillus acidophilus, found in certain brands of yogurt, helps reduce antibiotic-associated diarrhea in adults. Probiotics are also found in miso and other fermented foods.

Probiotics occur naturally in some foods, are added to others, or can be taken as concentrated supplements. “There are hundreds of probiotics,” Parkman says. “Each one is a little different. You may need to experiment to determine which one, if any, works for you.”

Probiotics supplements are sold in drugstores, groceries, and health food stores in liquid, powder, and capsule forms. They are sometimes kept in a refrigerated section because they need to be protected from heat. You should talk to your doctor before taking probiotics, to make sure they’re safe to use with your other treatment plans.

A Prescription for Caution

To avoid antibiotic-associated diarrhea, it’s best to take antibiotics only when your healthcare provider believes they are absolutely necessary. Antibiotics do not combat viral infections such as the cold and flu; they are effective only against bacterial infections.

Adjusting your diet may help you avoid or ease diarrhea symptoms until you finish your antibiotics regimen. Drink water to stay hydrated and replace any fluids lost to diarrhea. Most important, if your symptoms worsen or don’t clear up after you take your medication, talk to your doctor.

Why do some antibiotics cause diarrhea and is this a cause for concern?

Question – I have recently completed a course of antibiotics prior to having a dental procedure. Now I am experiencing diarrhea. Should I be concerned?
Answer – Antibiotic therapy is a common source of diarrhea in both hospitalized patients and outpatients. Approximately 20% of patients taking antibiotics will develop diarrhea.

There are two common causes of diarrhea in this setting.

Change in normal colonic flora – Antibiotics can cause a change in the normal colonic flora or the type of bacteria that normally reside in the colon. Large numbers of bacteria reside in the colon, which play a very important role in maintaining the integrity of the lining (mucosa) of the colon and assisting in digestion of unabsorbed carbohydrates.

When antibiotics are taken, they alter the number and types of bacteria present in the colon. The result is an impaired absorption of carbohydrates. This leads to water secretion and looser stools. The colonic bacteria are also crucial in producing organic acids, which act as vital nutrients in maintaining mucosal integrity. Should the mucosal integrity be impaired, one’s ability to reabsorb water in the colon will be limited. This can contribute to increased stool volume and diarrhea.

C. difficile – The second factor, which can cause diarrhea after antibiotic use, is C. difficile colitis. C. difficile is a bacterium that can increase in number after a course of antibiotics. This bacterium produces a toxin that causes inflammatory changes in the colon. These inflammatory changes result in both impaired water reabsorption in the colon and secretion of fluid resulting in diarrhea.

Probiotics

Probiotics, which are microorganisms that are ingested to provide a beneficial effect, have been shown to decrease the risk of antibiotic associated diarrhea. There are numerous preparations available over-the-counter. Discuss treatment options using probiotics with your healthcare provider.
– Thomas Puetz, MD

Contributor

  • Thomas Puetz, MD, Gastroenterology, Aurora Advanced Healthcare, Mequon, WI

Common use
Zithromax is a semi-synthetic macrolide antibiotic chemically related to erythromycin which is active against majority of species of gram positive and gram negative microorganisms such as genus Staphylococcus; S. aureus, S. pneumoiane, S. pyogenes, S. agalactiae, Haemophilus influenzae and parainfluenzae, Moraxela catarrhalis, Bacteroides fragilis, Escherichia coli, Bordetella ssp., Borrelia burgdorferi, Haemophilus ducreui, Nisseria gonorrhoeae Ø Chlamidia trachomati. In vitro it showed activity against Legionella pneumophila, Mycoplasma pneumoiae hominis, Helicobacter pylori, Toxoplasma gondii, Ureaplasma urealiticum. As a Macrolide antibiotic Zithromax inhibits bacterial protein synthesis and prevents bacteria from growth and propagation. It is used to treat infections of upper and low respiratory organs (tonsillitis, otitis, sinusitis, pneumonia), urogenital infections (urethritis, prostatitis, cervicitis, adnexitis caused by chlamydia, gonorrhea, early syphilis), intestinal infections, ulcer of stomach and duodenum.
Dosage and directions
Take exactly as prescribed and do not discontinue your treatment even if you feel fine and your symptoms improved without permission of your doctor. Take Zithromax tablet with a big glass of water. To prepare a liquid suspension form one dose packet mix one packet with 2 ounces of water, shake and drink at once. Do not use the suspension which was prepared longer than 12 hours ago. Tablets and suspension can be taken with or without food while capsules should be taken on an empty stomach 2 hours before or after a meal.
Precautions
There are no evidences if Zithromax affects an unborn baby or excretes in a breast milk. This medication should be used in pregnant and breastfeeding women only if expected benefit prevails over potential risk for the baby.
Contraindications
Hypersensitivity to Zithromax and related drugs such as azithromycin or erythromycin.
Possible side effect
Among side effects may be diarrhea or loose stools, nausea, abdominal pain, and vomiting, uneven heartbeats, loss of appetite, dark urine, clay-colored stools, jaundice, fever, rash, red skin, headache. You should call your doctor and inform about such symptoms or get immediate medical attention.
Drug interaction
Zithromax is not recommended to take with aluminum- or magnesium- based antacids, such as Mylanta or Maalox as they decrease its absorption in the intestine.
Missed dose
Take the missed dose when you remember. If it is almost time of the next intake just skip it and return to your schedule.
Overdose
Symptoms of overdose may appear as nausea, vomiting, diarrhea, and stomach discomfort. In this case look for immediate medical attention.
Storage
Store at room temperature between 59-77 F (15-25 C) away from light and moisture, kids and pets. Do not store the liquid longer than 10 days.
Disclaimer
We provide only general information about medications which does not cover all directions, possible drug integrations, or precautions. Information at the site cannot be used for self-treatment and self-diagnosis. Any specific instructions for a particular patient should be agreed with your health care adviser or doctor in charge of the case. We disclaim reliability of this information and mistakes it could contain. We are not responsible for any direct, indirect, special or other indirect damage as a result of any use of the information on this site and also for consequences of self-treatment.

Common use
Zithromax is a semi-synthetic macrolide antibiotic chemically related to erythromycin which is active against majority of species of gram positive and gram negative microorganisms such as genus Staphylococcus; S. aureus, S. pneumoiane, S. pyogenes, S. agalactiae, Haemophilus influenzae and parainfluenzae, Moraxela catarrhalis, Bacteroides fragilis, Escherichia coli, Bordetella ssp., Borrelia burgdorferi, Haemophilus ducreui, Nisseria gonorrhoeae Ø Chlamidia trachomati. In vitro it showed activity against Legionella pneumophila, Mycoplasma pneumoiae hominis, Helicobacter pylori, Toxoplasma gondii, Ureaplasma urealiticum. As a Macrolide antibiotic Zithromax inhibits bacterial protein synthesis and prevents bacteria from growth and propagation. It is used to treat infections of upper and low respiratory organs (tonsillitis, otitis, sinusitis, pneumonia), urogenital infections (urethritis, prostatitis, cervicitis, adnexitis caused by chlamydia, gonorrhea, early syphilis), intestinal infections, ulcer of stomach and duodenum.
Dosage and directions
Take exactly as prescribed and do not discontinue your treatment even if you feel fine and your symptoms improved without permission of your doctor. Take Zithromax tablet with a big glass of water. To prepare a liquid suspension form one dose packet mix one packet with 2 ounces of water, shake and drink at once. Do not use the suspension which was prepared longer than 12 hours ago. Tablets and suspension can be taken with or without food while capsules should be taken on an empty stomach 2 hours before or after a meal.
Precautions
There are no evidences if Zithromax affects an unborn baby or excretes in a breast milk. This medication should be used in pregnant and breastfeeding women only if expected benefit prevails over potential risk for the baby.
Contraindications
Hypersensitivity to Zithromax and related drugs such as azithromycin or erythromycin.
Possible side effect
Among side effects may be diarrhea or loose stools, nausea, abdominal pain, and vomiting, uneven heartbeats, loss of appetite, dark urine, clay-colored stools, jaundice, fever, rash, red skin, headache. You should call your doctor and inform about such symptoms or get immediate medical attention.
Drug interaction
Zithromax is not recommended to take with aluminum- or magnesium- based antacids, such as Mylanta or Maalox as they decrease its absorption in the intestine.
Missed dose
Take the missed dose when you remember. If it is almost time of the next intake just skip it and return to your schedule.
Overdose
Symptoms of overdose may appear as nausea, vomiting, diarrhea, and stomach discomfort. In this case look for immediate medical attention.
Storage
Store at room temperature between 59-77 F (15-25 C) away from light and moisture, kids and pets. Do not store the liquid longer than 10 days.
Disclaimer
We provide only general information about medications which does not cover all directions, possible drug integrations, or precautions. Information at the site cannot be used for self-treatment and self-diagnosis. Any specific instructions for a particular patient should be agreed with your health care adviser or doctor in charge of the case. We disclaim reliability of this information and mistakes it could contain. We are not responsible for any direct, indirect, special or other indirect damage as a result of any use of the information on this site and also for consequences of self-treatment.

PMC

Diarrhoea is a common adverse effect of antibiotic treatments. Antibiotic associated diarrhoea occurs in about 5-30% of patients either early during antibiotic therapy or up to two months after the end of the treatment.1–3 The frequency of antibiotic associated diarrhoea depends on the definition of diarrhoea, the inciting antimicrobial agents, and host factors.

Almost all antibiotics, particularly those that act on anaerobes, can cause diarrhoea, but the risk is higher with aminopenicillins, a combination of aminopenicillins and clavulanate, cephalosporins, and clindamycin.1,4,5 Host factors for antibiotic associated diarrhoea include age over 65, immunosuppression, being in an intensive care unit, and prolonged hospitalisation.6

Clinical presentations of antibiotic associated diarrhoea range from mild diarrhoea to fulminant pseudomembranous colitis. The latter is characterised by a watery diarrhoea, fever (in 80% of cases), leucocytosis (80%), and the presence of pseudomembranes on endoscopic examination. Severe complications include toxic megacolon, perforation, and shock.

Antibiotic associated diarrhoea results from disruption of the normal microflora of the gut by antibiotics. This microflora, composed of 1011 bacteria per gram of intestinal content, forms a stable ecosystem that permits the elimination of exogenous organisms. Antibiotics disturb the composition and the function of this flora and enable overgrowth of micro-organisms that induce diarrhoea. Since demonstration of its role in 1978, Clostridium difficile has emerged as the major enteropathogen of antibiotic associated diarrhoea.3 This anaerobic spore forming bacteria is responsible for 10-25% of cases of antibiotic associated diarrhoea and for virtually all cases of pseudomembranous colitis.3 It works by secreting two potent toxins that cause mucosal damage and inflammation of the colon. Other infectious agents reported to be responsible for antibiotic associated diarrhoea include C perfringens, Staphylococcus aureus, Candida spp, Klebsiella oxytoca, and Salmonella spp.7 However, their role in the pathogenesis of diarrhoea is still debated because most of them are considered to be usual commensal bacteria of the gut flora. Antibiotic associated diarrhoea can also result from a decrease in metabolism of carbohydrates and bile acids.7

Managing the diarrhoea depends on the clinical presentation and the inciting agent.7–10 In mild to moderate diarrhoea conventional measures include rehydration or discontinuation of the inciting agent or its replacement by an antibiotic with a lower risk of inducing diarrhoea, such as quinolones, co-trimoxazole, or aminoglycosides. In 22% of cases of diarrhoea related to C difficile, withdrawal of the inciting agent will lead to resolution of clinical signs in three days.11

In cases of severe or persistent antibiotic associated diarrhoea, the challenge is to identify C difficile associated infections since this is the most common identifiable and treatable pathogen. Diagnosis relies on detecting toxins A or B in stools. Tissue culture assay is the gold standard, although it is time consuming. Enzyme immunoassays for toxins A or B have a good specificity but a false negative rate of 10-20%.

Treatment of C difficile related diarrhoea is based on oral metronidazole (250 mg four times daily) or oral vancomycin (125 mg four times daily) for 10 days.11,12 The response to metronidazole or vancomycin is similar (>90%), and diarrhoea usually resolves in two or three days. The Infectious Diseases Society of America, the American College of Gastroenterology, and the Society for Hospital Epidemiology of America recommend metronidazole as the first line of treatment to prevent the emergence of vancomycin resistant organisms.9,10 Vancomycin should be reserved for those with severe illness, intolerance to metronidazole, failure to respond to metronidazole, or pregnancy. Antiperistaltic agents should be avoided because of the risk of retention of toxins in the lumen. About 20% of patients with C difficile related diarrhoea will relapse. Most patients will respond to another course of metronidazole or vancomycin, but 5% will experience several relapses; the management of these remains controversial.

As antibiotic associated diarrhoea mostly results from a disequilibrium of the normal intestinal flora, research has focused on the benefits of administering living organisms (probiotics or biotherapeutic agents) to restore the normal flora. Numerous probiotics such as Lactobacillus acidophilus, L casei GG, L bulgaricus, Bifidobacterium bifidum, B longum, Enterococcus faecium, Streptococcus thermophilus, or Saccharomyces boulardii have been tested for the treatment and prevention of antibiotic associated diarrhoea.13 The benefits of probiotics are unproved as few have been evaluated in double blind placebo controlled studies. The results of the small and open trials of treatment are conflicting.

Most studies with probiotics have assessed their use in preventing antibiotic associated diarrhoea. In this issue D’Souza et al report a meta-analysis of nine randomised double blind trials comparing probiotics with placebo in the prevention of diarrhoea (p 1361).14 Among these studies, four trials were used S boulardii and five Lactobacillus. Their results suggest that probiotics are useful in prevention. The expected advantages of probiotics include ease of administration, cost effectiveness, and relative lack of side effects. However, several cases of bacteraemia with S boulardii have been reported, which should prompt caution in the use of this yeast in immunosuppressed patients or patients with underlying disorders.

The key measure for preventing antibiotic associated diarrhoea, however, is to limit antibiotic use. Probiotics have proved useful in preventing diarrhoea, but the number of clinical trials is limited and further controlled trials using different probiotics are needed. In the case of C difficile related diarrhoea hygiene measures (single rooms, use of gloves, and handwashing) should be systematically associated with treatment in order to prevent transmission and dissemination of this nosocomial bacteria.

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