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nitrofurantoin macrocrystals
Macrobid, Macrodantin

nitrofurantoin microcrystals
Apo-Nitrofurantoin†, Furadantin, Furalan, Macrodantin, Novo-Furantoin†

Pregnancy Risk Category B

How supplied
nitrofurantoin macrocrystals

Capsules:
25 mg, 50 mg, 100 mg
nitrofurantoin microcrystals

Oral suspension:
25 mg/5 ml

Action
Unknown. Appears to interfere with bacterial enzyme systems and possibly with bacterial cell-wall formation.

Indications & dosage
Urinary tract infections due to susceptible
Escherichia coli, Staphylococcus aureus, enterococci; or certain strains of Klebsiella and Enterobacter--
Adults and children over age 12:
50 to 100 mg P.O. q.i.d. with meals and h.s.
Children ages 1 month to 12 years:
5 to 7 mg/kg P.O. daily, divided q.i.d.
Long-term suppression therapy--

Adults:
50 to 100 mg P.O. daily h.s.
Children:
1 mg/kg P.O. daily in a single dose h.s. or divided into two doses given q 12 hours.

Adverse reactions
CNS:
peripheral neuropathy, headache, dizziness, drowsiness, ascending polyneuropathy with high doses or renal impairment.
GI:
anorexia, nausea, vomiting, abdominal pain, diarrhea.
Hematologic:
hemolysis in patients with G6PD deficiency, agranulocytosis, thrombocytopenia.
Hepatic:
hepatitis, hepatic necrosis, elevated bilirubin and alkaline phosphatase.
Metabolic:
hypoglycemia.
Respiratory: pulmonary sensitivity reactions,
asthmatic attacks.
Skin:
maculopapular, erythematous, or eczematous eruption; transient alopecia; pruritus; urticaria; exfoliative dermatitis; Stevens-Johnson syndrome.
Other:
hypersensitivity reactions, anaphylaxis, drug fever, overgrowth of nonsusceptible organisms in urinary tract.

Interactions
Drug-drug.
Magnesium-containing antacids: decreased nitrofurantoin absorption. Separate administration times by 1 hour.
Probenecid, sulfinpyrazone:
increased blood levels and decreased urine levels. May result in increased toxicity and lack of therapeutic effect. Don't use together.
Drug-food.
Any food: increased absorption. Give drug with food.

Effects on diagnostic tests
Nitrofurantoin may cause false-positive results in urine glucose tests using cupric sulfate (such as Benedict's reagent, Fehling's solution, or Clinitest) because it reacts with these agents.

Contraindications
Contraindicated in infants ages 1 month and under and in patients with moderate to severe renal impairment, anuria, oliguria, or creatinine clearance under 60 ml/minute. Contraindicated in pregnancy at term (38 to 42 weeks) and during labor and delivery.

Nursing considerations

Patient teaching

*Liquid contains alcohol. **May contain tartrazine.  †Canada  ‡Australia  §U.K.  OTCOver the counter
Reactions may be common, uncommon, life-threatening, or COMMON AND LIFE-THREATENING

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