ACUTE, SUBACUTE, OR CHRONIC PULMONARY REACTIONS HAVE BEEN OBSERVED IN PATIENTS TREATED WITH NITROFURANTOIN. IF THESE REACTIONS OCCUR, NITROFURANTOIN ORAL SUSPENSION, USP SHOULD BE DISCONTINUED AND APPROPRIATED MEASURES TAKEN. REPORTS HAVE CITED PULMONARY REACTIONS AS A CONTRIBUTING CAUSE OF DEATH.
CHRONIC PULMONARY REACTIONS (DIFFUSE INTERSTITIAL PNEUMONITIS OR PULMONARY FIBROSIS, OR BOTH) CAN DEVELOP INSIDIOUSLY. THESE REACTIONS OCCUR RARELY AND GENERALLY IN PATIENTS RECEIVING THERAPY FOR SIX MONTHS OR LONGER. CLOSE MONITORING OF THE PULMONARY CONDITION OF PATIENTS RECEIVING LONG-TERM THERAPY IS WARRANTED AND REQUIRES THAT THE BENEFITS OF THERAPY BE WEIGHED AGAINST POTENTIAL RISKS.(see RESPIRATORY REACTIONS.)
Hepatotoxicity
Hepatic reactions, including hepatitis, cholestatic jaundice, chronic active hepatitis, and hepatic necrosis, occur rarely. Fatalities have been reported. The onset of chronic active hepatitis may be insidious, and patients should be monitored periodically for changes in biochemical tests that would indicate liver injury. If hepatitis occurs, the drug should be withdrawn immediately and appropriate measures should be taken.
Neuropathy
Peripheral neuropathy, which may become severe or irreversible, has occurred. Fatalities have been reported. Conditions such as renal impairment (creatinine clearance under 60 mL per minute or clinically significant elevated serum creatinine), anemia, diabetes mellitus, electrolyte imbalance, vitamin B deficiency, and debilitating disease may enhance the occurrence of peripheral neuropathy. Patients receiving long-term therapy should be monitored periodically for changes in renal function.
Optic neuritis has been reported rarely in postmarketing experience with nitrofurantoin formulations.
Hemolytic anemia
Cases of hemolytic anemia of the primaquine-sensitivity type have been induced by nitrofurantoin. Hemolysis appears to be linked to a glucose-6-phosphate dehydrogenase deficiency in the red blood cells of the affected patients. This deficiency is found in 10 percent of Blacks and a small percentage of ethnic groups of Mediterranean and Near-Eastern origin. Hemolysis is an indication for discontinuing Nitrofurantoin Oral Suspension, USP; hemolysis ceases when the drug is withdrawn.
Clostridium difficile-associated diarrhea
Clostridium difficile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including Nitrofurantoin Oral Suspension, and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile.
C. difficile produces toxins A and B which contribute to the development of CDAD. Hypertoxin producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents.
If CDAD is suspected or confirmed, ongoing antibiotic use not directed against C. difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of C. difficile, and surgical evaluation should be instituted as clinically indicated.
Nitrofurantoin Oral Suspension, USP is specifically indicated for the treatment of urinary tract infections when due to susceptible strains of Escherichia coli, enterococci, Staphylococcus aureus, and certain susceptible strains of Klebsiella and Enterobacter species.
Nitrofurantoin is not indicated for the treatment of pyelonephritis or perinephric abscesses.
Nitrofurantoins lack the broader tissue distribution of other therapeutic agents approved for urinary tract infections. Consequently, many patients who are treated with nitrofurantoin oral suspension, USP are predisposed to persistence or reappearance of bacteriuria. Urine specimens for culture and susceptibility testing should be obtained before and after completion of therapy. If persistence or reappearance of bacteriuria occurs after treatment with nitrofurantoin oral suspension, USP, other therapeutic agents with broader tissue distribution should be selected. In considering the use of nitrofurantoin oral suspension, USP, lower eradication rates should be balanced against the increased potential for systemic toxicity and for the development of antimicrobial resistance when agents with broader tissue distribution are utilized.
Nitrofurantoin, a synthetic chemical, is a stable, yellow, crystalline compound. Nitrofurantoin Oral Suspension, USP is an antibacterial agent for specific urinary tract infections. Nitrofurantoin Oral Suspension, USP is available in 25 mg/5 mL liquid suspension for oral administration.
Nitrofurantoin Oral Suspension, USP should be given with food to improve drug absorption and, in some patients, tolerance.
Adults
50 to100 mg four times a day -- the lower dosage level is recommended for uncomplicated urinary tract infections.
Pediatric Patients
5 to 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, USP (25 mg/5 mL) 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 to100 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 WARNINGSSECTION REGARDING RISKS ASSOCIATED WITH LONG TERM THERAPY.
Use lowest effective dose for the shortest duration consistent with treatment goals for the individual patient. These doses can be given without regard to timing of meals.
2.1 Osteoarthritis
For relief of the signs and symptoms of OA the recommended oral dose is 200 mg per day administered as a single dose or as 100 mg twice daily.
2.2 Rheumatoid Arthritis
For relief of the signs and symptoms of RA the recommended oral dose is 100 to 200 mg twice daily.
2.3 Juvenile Rheumatoid Arthritis
For the relief of the signs and symptoms of JRA the recommended oral dose for pediatric patients (age 2 years and older) is based on weight. For patients >10 kg to <25 kg the recommended dose is 50 mg twice daily. For patients >25 kg the recommended dose is 100 mg twice daily.
For patients who have difficulty swallowing capsules, the contents of a celecoxib capsule can be added to applesauce. The entire capsule contents are carefully emptied onto a level teaspoon of cool or room temperature applesauce and ingested immediately with water. The sprinkled capsule contents on applesauce are stable for up to 6 hours under refrigerated conditions (2-8° C/ 35-45° F).
2.4 Ankylosing Spondylitis
For the management of the signs and symptoms of AS, the recommended dose of celecoxib capsules is 200 mg daily in single (once per day) or divided (twice per day) doses. If no effect is observed after 6 weeks, a trial of 400 mg daily may be worthwhile. If no effect is observed after 6 weeks on 400 mg daily, a response is not likely and consideration should be given to alternate treatment options.
2.5 Management of Acute Pain and Treatment of Primary Dysmenorrhea
The recommended dose of celecoxib capsules is 400 mg initially, followed by an additional 200 mg dose if needed on the first day. On subsequent days, the recommended dose is 200 mg twice daily as needed.
2.6 Special Populations Hepatic insufficiency:
The daily recommended dose of celecoxib capsules in patients with moderate hepatic impairment (Child-Pugh Class B) should be reduced by 50%. The use of celecoxib in patients with severe hepatic impairment is not recommended [see Warnings and Precautions (5.5), Use in Specific Populations (8.6) and Clinical Pharmacology (12.3)].
Poor Metabolizers of CYP2C9 Substrates:
Patients who are known or suspected to be poor CYP2C9 metabolizers based on genotype or previous history/experience with other CYP2C9 substrates (such as warfarin, phenytoin) should be administered celecoxib with caution. Consider starting treatment at half the lowest recommended dose in poor metabolizers (i.e. CYP2C9*3/*3). Consider using alternative management in JRA patients who are poor metabolizers. [see Use in Specific populations (8.8), and Clinical Pharmacology (12.5)].
Nitrofurantoin Oral Suspension, USP should be given with food to improve drug absorption and, in some patients, tolerance.
Adults:
50 to 100 mg four times a day — the lower dosage level is recommended for uncomplicated urinary tract infections.
Pediatric Patients:
5 to 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, USP (25 mg/5 mL) 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 to 100 mg at bedtime may be adequate. For longterm 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.