Nitrofurantoin: Action, Uses , Administration, Dosage, Side Effects, Nursing Considerations by Nurses Note

 Nitrofurantoin

Uses of Nitrofurantoin

Prevention/treatment of UTI caused by susceptible gram-negative, gram-positive organisms, including E. coli, S. aureus, Enterococcus, Klebsiella, and Enterobacter.

Precautions of Nitrofurantoin

Contraindications: Hypersensitivity to nitrofurantoin. Anuria, oliguria, renal impairment (CrCl less than 60 mL/min), infants younger than 1 mo due to risk of hemolytic anaemia. Pregnancy at term, during labour, or delivery, or when the onset of labour is imminent. Pts with history of cholestatic jaundice or hepatic impairment with previous nitrofurantoin therapy. Cautions: Renal impairment, diabetes, electrolyte imbalance, anaemia, vitamin B deficiency, debilitated pts (greater risk of peripheral neuropathy), G6PD deficiency (greater risk of hemolytic anaemia), elderly pts, prolonged therapy (may cause pulmonary toxicity).

Action of Nitrofurantoin,

Inhibits bacterial enzyme systems, interfering with metabolism and cell wall synthesis. Therapeutic Effect: Bacteriostatic (bactericidal at high concentrations).

Pharmacokinetics

Microcrystalline form rapidly, completely absorbed; macrocrystalline form more slowly absorbed. Food increases absorption. Protein binding: 60%. Primarily concentrated in urine, kidneys. Metabolized in most body tissues. Primarily excreted in urine. Removed by hemodialysis. Half-life: 20–60 min.

Lifespan considerations

Pregnancy/Lactation: Readily crosses placenta. Distributed in breast milk. Contraindicated at term and during lactation when infant suspected of having G6PD deficiency. Children: No age-related precautions noted in pts older than 1 mo. Elderly: Avoid use. More likely to develop acute pneumonitis, peripheral neuropathy. Age-related renal impairment may require dosage adjustment.

Interactions

DRUG: Antacids containing magnesium trisilicate may decrease absorption. Probenecid may increase concentration, risk of toxicity. 

HERBAL: None significant. 

FOOD: None known. 

LAB VALUES: May increase serum ALT, AST, phosphorus. May decrease Hgb.

Availability (Rx) of  Nitrofurantoin

Capsules (Macrocrystalline [Macrobid]): 100 mg. Capsules (Macrocrystalline [Macrodantin]): 25 mg, 50 mg, 100 mg. Oral Suspension Microcrystalline [Furadantin]): 25 mg/5 mL.

Administration/handling of  Nitrofurantoin

PO

• Give with food, milk to enhance absorption, reduce GI upset.

• May mix suspension with water, milk, fruit juice; shake well.

Indications/routes/dosage of  Nitrofurantoin

UTI

PO: (Furadantin, Macrodantin): ADULTS, ELDERLY: 50–100 mg q6h for 7 days or at least 3 days after obtaining sterile urine. Maximum: 400 mg/day.

CHILDREN, ADOLESCENTS: 5–7 mg/kg/day in divided doses q6h for 7 days or at least 3 days after obtaining sterile urine. Maximum: 400 mg/day.

PO: (Macrobid): ADULTS, ELDERLY, ADOLESCENTS: 100 mg twice daily for 7 days.

Long-Term Prevention of UTI

PO: ADULTS, ELDERLY: 50–100 mg at bedtime. CHILDREN OLDER

THAN 1 MONTH: 1–2 mg/kg/day in 2 divided doses. Maximum: 100 mg/day.

Dosage in Renal Impairment

Contraindicated in pts with CrCl less than 60 mL/min.

Dosage in Hepatic Impairment

No dose adjustment.

Side effects of  Nitrofurantoin

Frequent: Anorexia, nausea, vomiting, dark urine. Occasional: Abdominal pain, diarrhoea, rash, pruritus, urticaria, hypertension, headache, dizziness, drowsiness. Rare: Photosensitivity, transient alopecia, asthmatic exacerbation in those with history of asthma.

Adverse effects/toxic reactions of  Nitrofurantoin

Superinfection, hepatotoxicity, peripheral neuropathy (may be irreversible), Stevens-Johnson syndrome, permanent pulmonary impairment, anaphylaxis occur rarely.

Nursing considerations of  Nitrofurantoin

Baseline assessment

Question for history of asthma. Evaluate baseline renal function, LFT. Question medical history as listed in Precautions, and screen for contraindications.

Intervention/evaluation

Monitor CBC, BMP, LFT; I&O. Monitor daily pattern of bowel activity, stool consistency. Assess skin for rash, and urticaria. Be alert for numbness/tingling, of lower extremities (may signal onset of peripheral neuropathy). Observe for signs of hepatotoxicity (fever, rash, arthralgia, hepatomegaly). Monitor respiratory status, esp. in pts with asthma.

Patient/ family teaching

• Urine may become dark yellow/brown.

• Take with food, milk for best results, to reduce GI upset.

• Complete full course of therapy.

• Avoid sun, and ultraviolet light; use sunscreen, wear protective clothing.

• Report cough, fever, chest pain, difficulty breathing, numbness/tingling of fingers, toes.

• Rare occurrence of alopecia is transient.