Nitrofurantoin Oral Suspension should be given with food to improve drug absorption and, in some patients, tolerance.
Adults
50-100 mg four times a day -- the lower dosage level is recommended for uncomplicated urinary tract infections.
Pediatric Patients
5-7 mg/kg of body weight per 24 hours, given in four divided doses (contraindicated under one month of age).
The following table is based on an average weight in each range receiving 5 to 6 mg/kg of body weight per 24 hours, given in four divided doses. It can be used to calculate an average dose of Nitrofurantoin Oral Suspension (25 mg/5mL) for pediatric patients.
Table 3: Pediatric Dosing Table
Weight in Kilograms (kg)
Pediatric Doses (milliliters) and Frequency
7 kg to 11 kg
2.5 mL Four times Daily
12 kg to 21 kg
5 mL Four times Daily
22 kg to 30 kg
7.5 mL Four times Daily
31 kg to 41 kg
10 mL Four times Daily
42 kg or greater
See Adult Dose
Therapy should be continued for one week or for at least 3 days after sterility of the urine is obtained. Continued infection indicates the need for reevaluation.
For long-term suppressive therapy in adults, a reduction of dosage to 50-100 mg at bedtime may be adequate. For long-term suppressive therapy in pediatric patients, doses as low as 1 mg/kg per 24 hours, given in a single dose or in two divided doses, may be adequate. SEE WARNINGS SECTION REGARDING RISKS ASSOCIATED WITH LONG TERM THERAPY.