Description and Brand Names

Drug information provided by: Merative, Micromedex®

US Brand Name

  1. Furadantin
  2. Macrodantin

Canadian Brand Name

  1. Novo-Furan Suspension

Descriptions


Nitrofurantoin is used to treat urinary tract infections. This medicine is an antibiotic. It works by killing bacteria or preventing their growth. However, this medicine will not work for colds, flu, or other virus infections.

This medicine is available only with your doctor's prescription.

This product is available in the following dosage forms:

  • Suspension
  • Capsule

Before Using

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of nitrofurantoin in children 1 month of age and older. However, safety and efficacy have not been established in children younger than 1 month of age.

Geriatric

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of nitrofurantoin capsules in the elderly. However, elderly patients are more likely to have age-related heart, liver, lung, or kidney problems, which may require caution in patients receiving this medicine .

No information is available on the relationship of age to the effects of nitrofurantoin oral liquid in geriatric patients.

Breastfeeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Drug Interactions

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Cholera Vaccine, Live
  • Fluconazole
  • Levoketoconazole
  • Methotrexate

Other Interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Anemia or
  • Diabetes or
  • Mineral imbalance in the blood or
  • Vitamin B deficiency—May increase the chance for side effects.
  • Diarrhea or
  • Liver disease or
  • Lung disease—Use with caution. May make these conditions worse.
  • Glucose-6-phosphate dehydrogenase (G6PD) deficiency (an enzyme problem in red blood cells)—May cause hemolytic anemia (red blood cells are destroyed) in patients with this condition.
  • Kidney disease (not infection)—Use with caution. The effects may be increased because of slower removal of the medicine from the body.
  • Kidney disease, severe or
  • Liver disease, history of or
  • Trouble urinating—Should not be used in patients with these conditions.

Proper Use

Take this medicine only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.

Nitrofurantoin is best taken with food or milk. This may lessen stomach upset and help your body to absorb the medicine.

Shake the oral liquid forcefully before each dose to make sure the medicine is evenly mixed. Use a specially marked measuring spoon or other device to measure each dose accurately. The average household teaspoon may not hold the right amount of liquid.

Swallow the capsule whole. Do not open, crush, or chew the capsule before swallowing it.

Do not take antacids containing magnesium trisilicate (eg, Genaton®) while you are using nitrofurantoin.

Keep using this medicine for the full treatment time, even if you feel better after the first few doses. Your infection may not clear up if you stop using the medicine too soon.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage forms (capsules and tablets):
    • For prevention of urinary tract infections:
      • Adults—50 to 100 milligrams (mg) at bedtime.
      • Children 1 month of age and older—Dose is based on body weight and must be determined by your doctor.
      • Children younger than 1 month of age—Use is not recommended.
    • For treatment of urinary tract infections:
      • Adults—50 to 100 milligrams (mg) 4 times a day.
      • Children 1 month of age and older—Dose is based on body weight and must be determined by your doctor.
      • Children younger than 1 month of age—Use is not recommended.
  • For oral dosage form (extended-release capsules):
    • For treatment of urinary tract infections:
      • Adults and children 12 years of age and older—100 milligrams (mg) every 12 hours for 7 days.
      • Children younger than 12 years of age—Use and dose must be determined by your doctor.
  • For oral dosage form (suspension):
    • For treatment of urinary tract infections:
      • Adults and children weighing 40 kilograms (kg) or more—50 to 100 milligrams (mg) 4 times a day.
      • Children 1 month of age and older—Dose is based on body weight and must be determined by your doctor. The dose is usually 5 milligram per kilogram (mg/kg) of body weight or 7 mg/kg of body weight per 24 hours given in 4 divided doses.
        • 25 milligram (mg)/5 milliliters (mL) suspension:
          • Weighing more than 30 kilograms (kg) to 40 kg—10 mg 4 times a day.
          • Weighing more than 25 kg to 30 kg—8.5 mg 4 times a day.
          • Weighing more than 20 kg to 25 kg—7 mg 4 times a day.
          • Weighing more than 14 kg to 20 kg—5 mg 4 times a day.
          • Weighing more than 10 kg to 14 kg—3.5 mg 4 times a day.
          • Weighing more than 7 kg to 10 kg—2.5 mg 4 times a day.
          • Weighing more than 5 kg to 7 kg—1.8 mg 4 times a day.
          • Weighing more than 4 kg to 5 kg—1.4 mg 4 times a day.
          • Weighing 4 kg or less—1 mg 4 times a day.
        • 50 mg/5 mL suspension:
          • Weighing more than 30 kilograms (kg) to 40 kg—5 mg 4 times a day.
          • Weighing more than 25 kg to 30 kg—4.25 mg 4 times a day.
          • Weighing more than 20 kg to 25 kg—3.5 mg 4 times a day.
          • Weighing more than 14 kg to 20 kg—2.5 mg 4 times a day.
          • Weighing more than 10 kg to 14 kg—1.75 mg 4 times a day.
          • Weighing more than 7 kg to 10 kg—1.25 mg 4 times a day.
          • Weighing more than 5 kg to 7 kg—0.9 mg 4 times a day.
          • Weighing more than 4 kg to 5 kg—0.7 mg 4 times a day.
          • Weighing 4 kg or less—0.5 mg 4 times a day.
      • Children younger than 1 month of age—Use is not recommended.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Precautions

It is very important that your doctor check your or your child's progress while you are using this medicine. This will allow your doctor to see if the medicine is working properly and to decide if you should continue to use it. Blood and urine tests may be needed to check for unwanted effects.

If your or your child's symptoms do not improve within a few days, or if they become worse, check with your doctor.

Using this medicine can harm your unborn baby. Tell your doctor right away if you think you have become pregnant.

This medicine may cause serious allergic reactions, including anaphylaxis, which can be life-threatening and require immediate medical attention. Call your doctor right away if you or your child have a rash, itching, hives, hoarseness, trouble breathing or swallowing, or any swelling of your hands, face, mouth, or throat after you take this medicine.

This medicine may cause lung problems (eg, pneumonitis, pulmonary fibrosis). Check with your doctor right away if you have chest pain, chills, cough, fever, general feeling of discomfort or illness, thickening of bronchial secretions, or trouble breathing.

Diabetic patients that use urine sugar tests should be careful when using this medicine. Nitrofurantoin may cause false test results with some urine sugar tests. Check with your doctor before changing your diet or the dose of your diabetes medicine.

Check with your doctor right away if you or your child have pain or tenderness in the upper stomach, pale stools, dark urine, loss of appetite, nausea, unusual tiredness or weakness, or yellow eyes or skin. These could be symptoms of a serious liver problem.

Tell your doctor right away if you start having numbness, tingling, or burning pain in your hands, arms, legs, or feet. These may be symptoms of a condition called peripheral neuropathy.

This medicine may cause hemolytic anemia. Check with your doctor right away if you have back, leg, or stomach pain, bleeding gums, chills, dark urine, fatigue, fever, general body swelling, headache, loss of appetite, nausea or vomiting, nosebleeds, pale skin, sore throat, trouble breathing, or yellowing of the eyes or skin.

Nitrofurantoin may cause diarrhea, and in some cases it can be severe. It may occur 2 months or more after you or your child stop taking this medicine. Do not take any medicine to treat diarrhea without first checking with your doctor. Diarrhea medicines may make the diarrhea worse or make it last longer. If you have any questions about this or if mild diarrhea continues or gets worse, check with your doctor.

This medicine may cause the urine to become a rust-yellow to brown color. This side effect does not require medical attention.

Before you have any medical tests, tell the medical doctor in charge that you are using this medicine. The results of some tests (eg, urine glucose tests) may be affected by this medicine.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

  1. Changes in facial skin color
  2. chest pain
  3. chills
  4. cough
  5. fever
  6. general feeling of discomfort or illness
  7. hives, itching, skin rash
  8. hoarseness
  9. joint or muscle pain
  10. sudden trouble swallowing or breathing
  11. swelling of the face, mouth, hands, or feet
  12. trouble breathing

Less common

  1. Black, tarry stools
  2. blood in the urine or stools
  3. burning, numbness, tingling, or painful sensations
  4. dizziness
  5. drowsiness
  6. headache
  7. pinpoint red spots on the skin
  8. sore throat
  9. unsteadiness or awkwardness
  10. unusual bleeding or bruising
  11. unusual tiredness or weakness
  12. weakness in the arms, hands, legs, or feet

Rare

  1. Blindness
  2. blistering, peeling, or loosening of the skin
  3. blue-yellow color blindness
  4. bluish color of the fingernails, lips, skin, palms, or nail beds
  5. blurred vision or loss of vision, with or without eye pain
  6. bulging soft spot on the head of an infant
  7. change in the ability to see colors, especially blue or yellow
  8. chest tightness
  9. confusion
  10. cracks in the skin
  11. dark urine
  12. decreased vision
  13. diarrhea
  14. diarrhea, watery and severe, which may also be bloody
  15. eye pain
  16. general tiredness and weakness
  17. light-colored stools
  18. loss of appetite
  19. loss of heat from the body
  20. mental depression
  21. mood or mental changes
  22. nausea or vomiting
  23. pale skin
  24. pale stools
  25. red skin lesions, often with a purple center
  26. red, irritated eyes
  27. red, swollen skin
  28. red, thickened, or scaly skin
  29. skin rash
  30. sores, ulcers, or white spots on the lips or in the mouth
  31. stomach pain
  32. swollen or painful glands
  33. tenderness of salivary glands
  34. unpleasant breath odor
  35. upper right abdominal pain
  36. visual changes
  37. vomiting of blood
  38. yellow eyes or skin

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

  1. Diarrhea
  2. gas

Incidence not known

  1. Dizziness or lightheadedness
  2. feeling of constant movement of self or surroundings
  3. lack or loss of strength
  4. loss of hair, temporary
  5. sensation of spinning
  6. uncontrolled eye movements

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.