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Generic Name: Nitrofurantoin Capsules (nye troe fyoor AN toyn)
Brand Name: Macrobid, Macrodantin

Medically reviewed by Last updated on Jul 23, 2020.

Uses of Macrobid:

  • It is used to treat or prevent a urinary tract infection (UTI).

What do I need to tell my doctor BEFORE I take Macrobid?

For all patients taking Macrobid (nitrofurantoin capsules):

  • If you have an allergy to nitrofurantoin or any other part of Macrobid (nitrofurantoin capsules).
  • If you are allergic to Macrobid (nitrofurantoin capsules); any part of Macrobid (nitrofurantoin capsules); or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
  • If you have kidney disease.
  • If you have trouble passing urine.
  • If Macrobid (nitrofurantoin capsules) caused liver problems before.
  • If you are more than 38 weeks pregnant.
  • If you are breast-feeding or plan to breast-feed.


  • If your child is younger than 1 month of age. Do not give Macrobid (nitrofurantoin capsules) to an infant younger than 1 month of age.

This is not a list of all drugs or health problems that interact with Macrobid (nitrofurantoin capsules).

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take Macrobid (nitrofurantoin capsules) with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take Macrobid?

  • Tell all of your health care providers that you take Macrobid (nitrofurantoin capsules). This includes your doctors, nurses, pharmacists, and dentists.
  • Be careful if you have G6PD deficiency. Anemia may happen.
  • This medicine may affect certain lab tests. Tell all of your health care providers and lab workers that you take Macrobid (nitrofurantoin capsules).
  • Do not use longer than you have been told. A second infection may happen.
  • Very bad and sometimes deadly lung problems have rarely happened with Macrobid (nitrofurantoin capsules). Most of the time, this happens in people who are taking Macrobid (nitrofurantoin capsules) for 6 months or longer. Lung problems may happen without warning signs. If you take Macrobid (nitrofurantoin capsules) for a long time, your doctor will watch your lung function. Call your doctor right away if you have fever, chills, chest pain, a cough that is not normal, or trouble breathing or other breathing problems.
  • If you are 65 or older, use Macrobid (nitrofurantoin capsules) with care. You could have more side effects.
  • Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using Macrobid (nitrofurantoin capsules) while you are pregnant.

How is this medicine (Macrobid) best taken?

Use Macrobid (nitrofurantoin capsules) as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • Take Macrobid (nitrofurantoin capsules) with food.
  • Keep taking Macrobid (nitrofurantoin capsules) as you have been told by your doctor or other health care provider, even if you feel well.
  • Drink lots of noncaffeine liquids unless told to drink less liquid by your doctor.
  • Do not take antacids that have magnesium trisilicate in them with Macrobid (nitrofurantoin capsules).

What do I do if I miss a dose?

  • Take a missed dose as soon as you think about it.
  • If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
  • Do not take 2 doses at the same time or extra doses.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Signs of a pancreas problem (pancreatitis) like very bad stomach pain, very bad back pain, or very bad upset stomach or throwing up.
  • Signs of lupus like a rash on the cheeks or other body parts, sunburn easy, muscle or joint pain, chest pain or shortness of breath, or swelling in the arms or legs.
  • Not able to control eye movements.
  • Feeling very tired or weak.
  • Diarrhea is common with antibiotics. Rarely, a severe form called C diff–associated diarrhea (CDAD) may happen. Sometimes, this has led to a deadly bowel problem (colitis). CDAD may happen during or a few months after taking antibiotics. Call your doctor right away if you have stomach pain, cramps, or very loose, watery, or bloody stools. Check with your doctor before treating diarrhea.
  • Liver problems have rarely happened with Macrobid (nitrofurantoin capsules). Sometimes, this has been deadly. Call your doctor right away if you have signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
  • Nerve problems have happened with Macrobid (nitrofurantoin capsules). Sometimes, these nerve problems have been very bad, have not gone away, or have been deadly. The chance of nerve problems may be higher in people who have kidney problems, anemia, diabetes, electrolyte problems, or low vitamin B. Call your doctor right away if you have a burning, numbness, or tingling feeling that is not normal.

What are some other side effects of Macrobid?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Headache.
  • Upset stomach or throwing up.
  • Not hungry.
  • Stomach pain or diarrhea.
  • Feeling dizzy, sleepy, tired, or weak.
  • Some people have had hair loss with Macrobid (nitrofurantoin capsules). This went back to normal when Macrobid (nitrofurantoin capsules) was stopped.
  • This medicine may change the color of the urine to brown. This is normal and not harmful.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at

If OVERDOSE is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out Macrobid?

  • Store at room temperature.
  • Store in a dry place. Do not store in a bathroom.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

Consumer information use

  • If your symptoms or health problems do not get better or if they become worse, call your doctor.
  • Do not share your drugs with others and do not take anyone else's drugs.
  • Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about Macrobid (nitrofurantoin capsules), please talk with your doctor, nurse, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Further information

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

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