Nitrofurantoin belongs to the class of medications called antibiotics. It is used to treat Urinary Tract Infections or bladder infections caused by certain types of bacteria. It works by killing the bacteria and preventing them from reproducing.

Nitrofurantoin may be available under multiple brand names and/or in several different forms. Any specific brand name of Nitrofurantoin may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of Nitrofurantoin may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking Nitrofurantoin without consulting your doctor.

Do not give Nitrofurantoin to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

The recommended dose of this medication for adults and children over 12 years old is 50 mg to 100 mg 4 times daily. Nitrofurantoin should be taken with food or milk to reduce the risk of stomach upset.

The recommended dose of nitrofurantoin for children is based on body size. It is calculated as 5 mg to 7 mg per kilogram of body weight per day, divided into 4 equal doses.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

It is important to take this medication exactly as prescribed by your doctor. Finish all of this medication, even if you start to feel better. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store Nitrofurantoin at room temperature, protect it from light and moisture, and keep it out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Nitrofurantoin. If you are concerned about side effects, discuss the risks and benefits of Nitrofurantoin with your doctor.

The following side effects have been reported by at least 1% of people taking Nitrofurantoin. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• Diarrhea
• gas
• headache
• nausea
• stomach pain
• vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• symptoms of liver problems (such as yellow eyes or skin, abdominal pain, pale stools, dark urine, itching, nausea, or fatigue)
• symptoms of low red blood cells (such as fatigue, weakness, decreased energy, or pale skin)
• symptoms of a lung reaction to the medication (such as Fever, chills, cough, chest pain, or difficulty breathing)
• symptoms of nerve damage (such as tingling, burning, pain, or numbness in the arms and legs; or difficulty controlling the muscles in the arms or legs)

Stop taking the medication and seek immediate medical attention if any of the following occur:

• symptoms of a serious skin reaction (such as a severe blistering skin rash that causes the skin to peel or fall off; fever; or bloodshot eyes)
• symptoms of a Anaphylaxis (severe allergic reaction) (such as Hives, difficulty breathing, and swelling of the face or throat)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Nitrofurantoin.

50 mg
Each scored tablet contains 50 mg of nitrofurantoin. Nonmedicinal ingredients: croscarmellose sodium, lactose monohydrate, magnesium stearate, and microcrystalline cellulose.

100 mg
Each scored tablet contains 100 mg of nitrofurantoin. Nonmedicinal ingredients: croscarmellose sodium, lactose monohydrate, magnesium stearate, and microcrystalline cellulose.

Do not take nitrofurantoin if you:

• are allergic to nitrofurantoin or any ingredients of the medication
• have significantly reduced kidney function
• are a pregnant woman in labour or a pregnant woman expecting to go into labour soon (i.e. close to your due date)

Do not give Nitrofurantoin to infants under one month of age.

There may be an interaction between nitrofurantoin and any of the following:

• antacids containing magnesium trisilicate
• bacillus Calmette-Guerin (BCG)
• Cholera vaccine
• Dapsone
• Eplerenone
• Methotrexate
• Norfloxacin
• prilocaine
• sodium picosulfate
• Spironolactone
• tetracaine
• typhoid vaccine

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Nitrofurantoin. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use Nitrofurantoin.

Anemia: Rarely, nitrofurantoin may cause low levels of red blood cells. This is more likely to happen if you have the genetic condition G-6-PD deficiency. If you experience symptoms of reduced red blood cell count (anemia) such as shortness of breath, feeling unusually tired, or pale skin, contact your doctor as soon as possible.

Bacterial resistance: Misuse of an antibiotic such as nitrofurantoin may lead to the growth of resistant bacteria that will not be killed by the antibiotic. If this happens, the antibiotic may not work for you in the future. Although you may begin to feel better when you first start taking nitrofurantoin, you need to take all the medication exactly as directed by your doctor to finish ridding your body of the infection and to prevent resistant bacteria from taking hold. Do not take nitrofurantoin or other antibiotics to treat a viral infection such as The Common Cold; antibiotics do not kill viruses, and using them to treat viral infections can lead to the growth of resistant bacteria.

Discolouration of urine: Nitrofurantoin may turn your urine a rust yellow or brown colour. This is a normal effect of the medication and is not a cause for concern.

Kidney function: If you have reduced kidney function or Kidney Disease, discuss with your doctor how Nitrofurantoin may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Nitrofurantoin, and whether any special monitoring is needed.

Liver function: Nitrofurantoin may affect liver function. If you have liver problems, discuss with your doctor how Nitrofurantoin may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Nitrofurantoin, and whether any special monitoring is needed.

Lung inflammation: Rarely, some people taking this medication have experienced lung inflammation (interstitial lung disease), causing difficulty breathing. This complication can be serious and sometimes fatal. If you experience new or worsening shortness of breath or cough (with or without fever) at any time while you are taking nitrofurantoin, contact your doctor immediately.

Nerve damage: Tingling, numbness, or pain have been reported with the use of nitrofurantoin. These effects may be more likely to occur for people who have other conditions that are linked to nerve damage such as Diabetes, certain vitamin deficiencies, or fluid and electrolyte problems.

Overgrowth of organisms: The use of Nitrofurantoin may cause an overgrowth of microorganisms not killed by the medication, possibly causing yeast infections or resistant bacteria.

Pregnancy: Nitrofurantoin should not be used during pregnancy unless the benefits outweigh the risks. Do not use Nitrofurantoin if you are in labour or expect to go into labour soon (i.e. you are close to your due date). If you become pregnant while taking Nitrofurantoin, contact your doctor immediately.

Breast-feeding: Nitrofurantoin passes into breast milk. If you are a breast-feeding mother and are taking nitrofurantoin, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children less than one month of age.