nitrofurantoin

Contraindicated in:

Hypersensitivity;
Hypersensitivity to parabens (suspension);
Oliguria, anuria, or significant renal impairment (CCr <60 mL/min);
History of cholestatic jaundice or hepatic impairment with previous use of nitrofurantoin;
OB: Pregnancy near term (38–42 wk gestation) and during labor/delivery (↑ risk of hemolytic anemia);
Pedi: Infants <1 mo (↑ risk of hemolytic anemia).

Use Cautiously in:

Glucose-6-phosphate dehydrogenase (G6PD) deficiency (↑ risk of hemolytic anemia, especially in Blacks and Mediterranean and Near Eastern ethnic groups);
Diabetes (↑ risk of neuropathy);
OB: Use during pregnancy only if potential fetal risk outweighs potential material benefit; Lactation: May cause hemolysis in infants with G6PD deficiency who are breastfed;
Geri: Appears on Beers list. ↑ risk of pulmonary toxicity, hepatotoxicity, and peripheral neuropathy, especially with long-term use, in older adults. Avoid use in older adults if CCr <30 mL/min or for long-term suppression of urinary tract infections.

Adv. Reactions/Side Effects ⬆ ⬇

EENT: nystagmus

GI: anorexia, nausea, vomiting, abdominal pain, CLOSTRIDIOIDES DIFFICILE-ASSOCIATED DIARRHEA (CDAD), diarrhea, HEPATOTOXICITY

GU: rust/brown discoloration of urine

Hemat: blood dyscrasias, hemolytic anemia

Neuro: dizziness, drowsiness, headache, peripheral neuropathy

Resp: PNEUMONITIS, PULMONARY FIBROSIS

Misc: hypersensitivity reactions

Interactions ⬆ ⬇

Drug-drug:

Probenecid prevents high urinary concentrations; may ↓ effectiveness.
Antacids may ↓ absorption.
↑risk of neurotoxicity with neurotoxic drugs.
↑risk of hepatotoxicity with hepatotoxic drugs.
↑risk of pneumonitis with drugs having pulmonary toxicity.

Availability ⬆ ⬇

(Generic available)

Tablets: 50 mg; 100 mg
Capsules (Macrodantin): 25 mg; 50 mg; 100 mg
Extended-release capsules (Macrobid): 100 mg
Oral suspension: 25 mg/5 mL; 50 mg/5 mL

Route/Dosage ⬆ ⬇

PO (Adults ): Treatment of active infection: 50–100 mg every 6 hr or 100 mg every 12 hr as extended-release product. Chronic suppression: 50–100 mg at bedtime.
PO (Children >1 mo): Treatment of active infection: 5–7 mg/kg/day divided every 6 hr; maximum dose: 400 mg/day. Chronic suppression: 1–2 mg/kg/day in 1–2 divided doses; maximum dose: 100 mg/day (unlabeled).

US Brand Names ⬆ ⬇

Furadantin, Macrobid, Macrodantin

Action ⬆ ⬇

Interferes with bacterial enzymes.

Therapeutic effects:

Bactericidal or bacteriostatic action against susceptible organisms.

Spectrum:

Many gram-negative and some gram-positive organisms, specifically:
- Citrobacter,
- Corynebacterium,
- Enterobacter,
- Escherichia coli,
- Klebsiella,
- Neisseria,
- Salmonella,
- Shigella,
- Staphylococcus aureus,
- Staphylococcus epidermidis,
- Enterococcus.

Classifications ⬆ ⬇

Therapeutic Classification: anti-infectives

Pharmacokinetics ⬆ ⬇

Absorption: Readily absorbed after oral administration. Absorption is slower but more complete with macrocrystals (Macrodantin).

Distribution: Minimally distributed to tissues (concentrated in urine).

Metabolism/Excretion: Partially metabolized by the liver; 30–50% excreted unchanged by the kidneys.

Half-Life: 20 min (↑ in renal impairment).

Time/Action Profile ⬆ ⬇

(urine levels)

ROUTE	ONSET	PEAK	DURATION
PO	unknown	30 min	6–12 hr

Patient/Family Teaching ⬆ ⬇

Explain purpose and side effects of medication to patient. Advise patient to read Patient Information before starting therapy. Instruct patient to take medication around the clock, as directed. Take missed doses as soon as remembered and space next dose 2–4 hr apart. Do not skip or double up on missed doses. Instruct patient to consult health care professional if no improvement is seen within a few days after initiation of therapy.
May cause dizziness or drowsiness. Caution patient to avoid driving or other activities requiring alertness until response to medication is known.
Inform patient that medication may cause a rust-yellow to brown discoloration of urine, which is not significant.
Advise patient to notify health care professional if fever, chills, cough, chest pain, dyspnea, skin rash, numbness or tingling of the fingers or toes, or intolerable GI upset occurs. Signs of superinfection (milky, foul-smelling urine; perineal irritation; dysuria) should also be reported.
Instruct patient to notify health care professional if fever and diarrhea develop, especially if stool contains blood, pus, or mucus. Advise patient not to treat diarrhea without consulting health care professional.
Rep: May cause fetal harm. Advise females of reproductive potential to notify health care professional if pregnancy is planned or suspected and to avoid breastfeeding during therapy and for 1 mo after last dose of therapy. May cause hemolytic anemia in pregnant patients at term (38–42 wk gestation), during labor and delivery, or when the onset of labor is imminent.

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Indications ⬇

Contraind./Precautions ⬆ ⬇