Proper Use

Drug information provided by: Merative, Micromedex®

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.

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