What is nitrofurantoin mono mac 100mg caps used for?


Generic Name: nitrofurantoin (NYE troe fue RAN toin)
Brand Names: Furadantin, Macrobid, Macrodantin, Nitro Macro

Medically reviewed by Sanjai Sinha, MD Last updated on Dec 22, 2018.

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What is nitrofurantoin?

Nitrofurantoin is an antibiotic that fights bacteria in the body.

Nitrofurantoin is used to treat urinary tract infections.

Nitrofurantoin may also be used for purposes not listed in this medication guide.

Important information

You should not take nitrofurantoin if you have severe kidney disease, urination problems, or a history of jaundice or liver problems caused by nitrofurantoin.

Do not take this medicine if you are in the last 2 to 4 weeks of pregnancy.

Before taking this medicine

You should not take nitrofurantoin if you are allergic to it, or if you have:

  • severe kidney disease;

  • a history of jaundice or liver problems caused by taking nitrofurantoin;

  • if you are urinating less than usual or not at all; or

  • if you are in the last 2 to 4 weeks of pregnancy.

Do not take nitrofurantoin if you are in the last 2 to 4 weeks of pregnancy.

To make sure nitrofurantoin is safe for you, tell your doctor if you have:

  • kidney disease;

  • anemia;

  • diabetes;

  • an electrolyte imbalance or vitamin B deficiency;

  • glucose-6-phosphate dehydrogenase (G6PD) deficiency; or

  • any type of debilitating disease.

FDA pregnancy category B. This medicine is not expected to be harmful to an unborn baby during early pregnancy. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

Nitrofurantoin can pass into breast milk and may harm a nursing baby. You should not breast-feed while you are taking this medicine.

Nitrofurantoin should not be given to a child younger than 1 month old.

How should I take nitrofurantoin?

Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Take nitrofurantoin with food.

Shake the oral suspension (liquid) well just before you measure a dose. Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.

You may mix your liquid dose with water, milk, or fruit juice to make it easier to swallow. Drink the entire mixture right away.

Use this medicine for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Skipping doses may also increase your risk of further infection that is resistant to antibiotics. Nitrofurantoin will not treat a viral infection such as the common cold or flu.

Nitrofurantoin is usually given for up to 3 to 7 days.

If you use this medicine long-term, you may need frequent medical tests at your doctor’s office.

Nitrofurantoin can cause unusual results with certain lab tests for glucose (sugar) in the urine. Tell any doctor who treats you that you are using nitrofurantoin.

Store at room temperature away from moisture, heat, and light.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking nitrofurantoin?

Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or has blood in it, call your doctor. Do not use any medicine to stop the diarrhea unless your doctor has told you to.

Avoid using antacids without your doctor’s advice. Use only the type of antacid your doctor recommends. Some antacids can make it harder for your body to absorb nitrofurantoin.

Nitrofurantoin side effects

Get emergency medical help if you have any of these signs of an allergic reaction to nitrofurantoin: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • diarrhea that is watery or bloody;

  • sudden chest pain or discomfort, wheezing, dry cough or hack;

  • new or worsening cough, trouble breathing;

  • fever, chills, body aches, tiredness, unexplained weight loss;

  • numbness, tingling, or pain in your hands or feet;

  • liver problems–nausea, upper stomach pain, itching, tired feeling, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes); or

  • lupus-like syndrome–joint pain or swelling with fever, swollen glands, muscle aches, chest pain, vomiting, unusual thoughts or behavior, and patchy skin color.

Serious side effects may be more likely in older adults and those who are ill or debilitated.

Common nitrofurantoin side effects may include:

  • headache, dizziness;

  • gas, upset stomach;

  • mild diarrhea; or

  • vaginal itching or discharge.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Nitrofurantoin dosing information

Usual Adult Dose for Cystitis:

Regular release: 50 to 100 mg orally 4 times a day for 1 week or for at least 3 days after urine sterility is obtained
Dual release: 100 mg orally twice a day for 7 days

Usual Adult Dose for Cystitis Prophylaxis:

Regular release: 50 to 100 mg orally once a day at bedtime

Usual Pediatric Dose for Cystitis:

Regular release:
1 month or older: 5 to 7 mg/kg/day (up to 400 mg/day) orally in 4 divided doses
Dual release:
Greater than 12 years: 100 mg orally twice a day for 7 days

Usual Pediatric Dose for Cystitis Prophylaxis:

Regular release:
1 month or older: 1 to 2 mg/kg/day (up to 100 mg/day) orally in 1 to 2 divided doses

What other drugs will affect nitrofurantoin?

Other drugs may interact with nitrofurantoin, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use nitrofurantoin only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Copyright 1996-2020 Cerner Multum, Inc. Version: 8.01.

Related questions

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  • Drug class: urinary anti-infectives

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  • Nitrofurantoin Capsules
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  • Nitrofurantoin (Advanced Reading)

Other brands: Macrobid, Macrodantin, Furadantin

Professional resources

  • Nitrofurantoin (AHFS Monograph)
  • … +4 more

Related treatment guides

  • Urinary Tract Infection
  • Prevention of Bladder infection
  • Bladder Infection



In clinical trials of Macrobid, the most frequent clinical adverse events that were reported as possibly or probably drug-related were nausea (8%), headache (6%): and flatulence (1.5%). Additional clinical adverse events reported as possibly or probably drug-related occurred in less than 1% of patients studied and are listed below within each body system in order of decreasing frequency:

Gastrointestinal: Diarrhea, dyspepsia, abdominal pain, constipation, emesis

Neurologic: Dizziness, drowsiness, amblyopia

Respiratory: Acute pulmonary hypersensitivity reaction (see WARNINGS)

Allergic: Pruritus, urticaria

Dermatologic: Alopecia

Miscellaneous: Fever, chills, malaise

The following additional clinical adverse events have been reported with the use of nitrofurantoin:

Gastrointestinal: Sialadenitis, pancreatitis. There have been sporadic reports of pseudomembranous colitis with the use of nitrofurantoin. The onset of pseudomembranous colitis symptoms may occur during or after antimicrobial treatment. (See WARNINGS.)

Neurologic: Peripheral neuropathy, which may become severe or irreversible, has occurred. Fatalities have been reported. Conditions such as renal impairment (creatinine clearance under 60 mL per minute or clinically significant elevated serum creatinine), anemia, diabetes mellitus, electrolyte imbalance, vitamin B deficiency, and debilitating diseases may increase the possibility of peripheral neuropathy. (See WARNINGS.)

Asthenia, vertigo, and nystagmus also have been reported with the use of nitrofurantoin.

Benign intracranial hypertension (pseudotumor cerebri), confusion, depression, optic neuritis, and psychotic reactions have been reported rarely. Bulging fontanels, as a sign of benign intracranial hypertension in infants, have been reported rarely.





In subacute pulmonary reactions, fever and eosinophilia occur less often than in the acute form. Upon cessation of therapy, recovery may require several months. If the symptoms are not recognized as being drug-related and nitrofurantoin therapy is not stopped, the symptoms may become more severe.

Acute pulmonary reactions are commonly manifested by fever, chills, cough, chest pain, dyspnea, pulmonary infiltration with consolidation or pleural effusion on x-ray, and eosinophilia. Acute reactions usually occur within the first week of treatment and are reversible with cessation of therapy. Resolution often is dramatic. (See WARNINGS.)

Changes in EKG (e.g., non-specific ST/T wave changes, bundle branch block) have been reported in association with pulmonary reactions.

Cyanosis has been reported rarely.

Hepatic: Hepatic reactions, including hepatitis, cholestatic jaundice, chronic active hepatitis, and hepatic necrosis, occur rarely. (See WARNINGS.)

Allergic: Lupus-like syndrome associated with pulmonary reaction to nitrofurantoin has been reported. Also, angioedema; maculopapular, erythematous, or eczematous eruptions; anaphylaxis; arthralgia; myalgia; drug fever; chills; and vasculitis (sometimes associated with pulmonary reactions) have been reported. Hypersensitivity reactions represent the most frequent spontaneously-reported adverse events in worldwide postmarketing experience with nitrofurantoin formulations.

Dermatologic: Exfoliative dermatitis and erythema multiforme (including Stevens-Johnson syndrome) have been reported rarely.

Hematologic: Cyanosis secondary to methemoglobinemia has been reported rarely.

Miscellaneous: As with other antimicrobial agents, superinfections caused by resistant organisms, e.g., Pseudomonas species or Candida species, can occur.

In clinical trials of Macrobid, the most frequent laboratory adverse events (1-5%), without regard to drug relationship, were as follows: eosinophilia, increased AST (SGOT), increased ALT (SGPT), decreased hemoglobin, increased serum phosphorus. The following laboratory adverse events also have been reported with the use of nitrofurantoin: glucose-6- phosphate dehydrogenase deficiency anemia (see WARNINGS), agranulocytosis, leukopenia, granulocytopenia, hemolytic anemia, thrombocytopenia, megaloblastic anemia. In most cases, these hematologic abnormalities resolved following cessation of therapy. Aplastic anemia has been reported rarely.

Read the entire FDA prescribing information for Macrobid (Nitrofurantoin)

Nitrofurantoin is an antibiotic that’s commonly prescribed to treat urine infections.

Nitrofurantoin comes as tablets and capsules (50mg and 100mg strengths) and as a liquid. It’s also available under the brand names Furadantin, Genfura and Macrobid.

What is nitrofurantoin used for?

  • Treating urinary tract infections (UTIs) caused by bacteria in adults and children aged three months and over.
  • Preventing UTIs in people who get lots of urine infections.
  • Preventing UTIs in people having a surgical procedure on the bladder or urinary tract.

Your doctor may want you to give a urine sample before prescribing this medicine. This will be sent to microbiology to make sure the type of bacteria causing your urine infection are susceptible to nitrofurantoin.

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How does nitrofurantoin work?

Nitrofurantoin is a type of medicine called an antibiotic. When you take it by mouth, high levels of nitrofurantoin get filtered out of the blood and into the urine by your kidneys. This puts the medicine right among the bacteria that are causing the urine infection.

Nitrofurantoin kills the bacteria by entering their cells and damaging their genetic material (DNA). This leaves the bacteria unable to repair themselves or to multiply and so clears up the infection.

Nitrofurantoin works quickly to treat urine infections and usually only requires a short course of three to seven days. If you get lots of UTIs your doctor may ask you to take this antibiotic on a regular basis for longer periods of time. This is to control the numbers of bacteria in your urine and stop UTIs coming back.

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Things to know before taking nitrofurantoin:

  • Nitrofurantoin can turn your urine a dark yellow or brown colour. This is normal and nothing to worry about – it’s due to the colour of the medicine.
  • It’s important to complete the prescribed course of nitrofurantoin when treating a UTI. If you stop treatment early because you feel better this makes it more likely that your infection will come back. It also increases the risk of the bacteria becoming resistant to the antibiotic.

Can I drink alcohol while taking nitrofurantoin?

Alcohol doesn’t affect nitrofurantoin itself, so it won’t cause a problem with the medication if you drink in moderation while taking it. However, it’s best to avoid drinking alcohol while you have a UTI – drink plenty of water instead to help flush the bacteria out of your bladder and urinary tract.

Can I drive while taking nitrofurantoin?

This antibiotic is very unlikely to affect your ability to drive, but if you find it does make you feel sleepy or dizzy then it’s best to avoid driving while taking it.

More information about nitrofurantoin

  • Who shouldn’t take nitrofurantoin?
  • How do you take nitrofurantoin?
  • What are the side effects of nitrofurantoin?
  • Can I take other medicines with nitrofurantoin?

Last updated: 14.02.2019

Helen Marshall, BPharm, MRPharmS Helen Marshall, BPharm, MRPharmS A UK registered pharmacist with a background in hospital pharmacy.

Nitrofurantoin and Alcohol

While Nitrofurantoin and alcohol do not have any known interactions, it is still not a good idea to mix the two. Moderate alcohol consumption (one glass a day for women and two glasses a day for men) has been shown to have no negative effect on Nitrofurantoin. However, if you drink excessive amounts, it could cause serious health problems and may reduce the drug’s effectiveness.

If you do plan to alcohol, no matter how little, you should let your doctor know. There may be other health considerations, beyond this one drug, that need to be considered.

If you are using Nitrofurantoin to treat a bladder or urinary tract infection you need to abstain from alcohol. Alcohol can exacerbate the infection, which can alter the effectiveness of the medication, and increase the length of time for recovery.

Another reason to avoid alcohol while taking any medication, is that is can delay you from noticing any adverse side effects. These side effects could be serious, so it’s important to remain as alert as possible, so you realise of you experience any.

If you are not sure if you are drinking too much in your situation, then consult your doctor about it. Your doctor will be able to tell you how much alcohol is acceptable for your condition and what other substances you need to abstain from while your body is healing.

View our full range of cystitis treatment

There’s a good reason you shouldn’t drink alcohol while you’re on antibiotics — but it’s probably not what you’ve been told

  • Alcohol and antibiotics are two things most people know not to mix. However, the truth is more complicated.
  • Although drinking while taking most antibiotics doesn’t pose a health risk, it can slow down your healing and lead to unpleasant side effects.
  • Some antibiotics should never be taken with alcohol due to dangerous reactions.

You’ve probably heard that you shouldn’t drink while on antibiotics. While it’s technically a myth that having a sip of something strong while treating an infection always poses a serious risk to your health, there are reasons to avoid mixing booze and antibiotics.

Here are the facts about why and when you should abstain from alcohol while on antibiotics.

First of all, you’re not going to immediately drop dead if you have a drink while on antibiotics.

Your doctor will likely caution you to avoid alcohol while you’re taking your course of antibiotics, but forgetting and having one glass of wine with dinner isn’t going to be the end of you.

According to the UK’s National Health Service, “it’s unlikely that drinking alcohol in moderation will cause problems if you’re taking most common antibiotics.”

Similarly, senior lecturer of medical sciences at The University of Adelaide Dr. Ian Musgrave told HuffPost, “for the vast majority of antibiotics, you don’t have to worry. Seriously, for most antibiotics, it doesn’t matter. Outside of — if you drink too much and then you won’t remember to take your antibiotics — which can then be a problem.”

This misconception was reportedly started by doctors in the 1950s to keep patients from having sex.

They tried to deter Netflix For real, according to Karl S. Kruszelnicki in ABC Science. When penicillin was first used to treat sexually transmitted infections in the 1950s, doctors considered it something of a miracle drug. However, there wasn’t a lot of understanding amongst patients about how antibiotics and STIs worked.

To keep patients from having sex immediately and give the antibiotics a chance to clear them of disease, Kruszelnicki said doctors warned them to not take the drugs with alcohol. The thought was the drinking would make the patients friskier, and that friskiness would lead to them reinfecting their partners or spreading the disease.

But in reality, drinking while taking antibiotics can make you feel even sicker.

Although combining happy hour with antibiotics isn’t going to create some lethal chemical reaction inside you, it will up your chances of experiencing negative side effects from both drugs. Because yes, alcohol is a drug.

According to the Mayo Clinic, many antibiotics can cause side effects like drowsiness, nausea, dizziness, and upset stomach. As you might have noticed, these are also side effects of alcohol consumption. Add in the fact that you’re likely taking antibiotics because you’re already unwell, and that’s a recipe for not feeling awesome after a night out.

“While antibiotics may not interfere with the absorption or action of most antibiotics, you’re nuts to do this. If you’re sick enough to be on antibiotics, you’re too sick to consume alcohol,” chair of Berkeley Wellness’ editorial board Dr. John Swartzberg told Thrillist.

Though alcohol won’t stop your antibiotics from working, it could stall your healing in other ways.

It could potentially make you feel sicker for a longer period of time. FOX Most antibiotics will remain effective if you indulge in modest alcohol consumption. However, that doesn’t mean that you’ll get better just as fast as if you hadn’t gone out for drinks.

There is clinical evidence that alcohol can slow wound healing and recovery from illness. One study suggested that drinking may affect wound healing and lead to impaired tissue repair and another study showed that alcohol may impact immunity and the body’s ability to heal from infections. Further research has given evidence that ethanol intoxication, i.e. being drunk, can increase the risk of infection following abdominal trauma.

Essentially, alcohol can keep you sicker for longer. If you don’t want to draw out your illness, consider skipping the booze.

Certain antibiotics can cause a serious reaction if mixed with alcohol.

Though most antibiotics won’t cause any blatantly terribly effects if taken with alcohol, some definitely will.

Drinking alcohol while on certain antibiotics will cause you to have an almost immediate and horrible reaction.

Metronidazole is a common antibiotic used to treat some dental and vaginal infections like bacterial vaginosis and pelvic inflammatory disease. You might also be prescribed this drug if you have rosacea. Tinidazole treats many of the same infections and can eliminate certain kinds of parasites.

If you drink while taking either of these drugs, you’re putting yourself at risk of severe nausea, vomiting, and diarrhea. These effects can be serious enough to land you in the hospital for dehydration and heart palpitations.

Taking trimethoprim-sulfamethoxazole, also known as Bactrim or Septra, can also lead to rapid heart rate and severe nausea when mixed with alcohol.

Mixing erythromycin with drinks can lead to heightened intoxication, or getting much drunker than you expected in a much shorter time frame. This is due to erythromycin’s tendency to cause faster gastric emptying, which leads to more alcohol absorption. This can lead to lethal alcohol poisoning.

Interestingly, the antibiotic disulfiram causes such intolerable symptoms when taken with alcohol that the drug is actually used as a treatment for alcohol abuse.

Although taking most antibiotics alongside a beer isn’t going to kill you, it can lead to unpleasant side effects that go beyond a normal hangover. Ultimately, you should probably just rest up.

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