What is the recommended dose and frequency of Nitrofurantoin (Macrobid) for Urinary Tract Infection (UTI)?

From the Guidelines

For uncomplicated urinary tract infections (UTIs), the recommended dose and frequency of Nitrofurantoin (Macrobid) is 100 mg taken orally twice daily for 5 days. This recommendation is based on the most recent and highest quality study, which suggests that this dosage is effective and has minimal resistance and propensity for collateral damage 1. The medication should be taken with food to improve absorption and reduce stomach upset. Patients should complete the entire course of antibiotics even if symptoms improve before finishing the prescription.

Key Considerations

• Macrobid works by concentrating in the urine where it interferes with bacterial cell wall production and metabolism, making it effective against many common UTI-causing organisms including E. coli.
• Patients should drink plenty of water while taking this medication and should be aware of potential side effects including nausea, headache, or urine discoloration.
• Macrobid is not recommended for patients with significant kidney impairment (creatinine clearance <30 mL/min) as it may not concentrate adequately in the urine to be effective.
• If symptoms worsen or do not improve within 3 days, patients should contact their healthcare provider.

Supporting Evidence

• A 2021 study published in the Annals of Internal Medicine recommends short-course antibiotics with either nitrofurantoin for 5 days, trimethoprim–sulfamethoxazole (TMP–SMZ) for 3 days, or fosfomycin as a single dose for women with uncomplicated bacterial cystitis 1.
• A 2011 study published in the Clinical Infectious Diseases journal also recommends nitrofurantoin monohydrate/macrocrystals (100 mg twice daily for 5 days) as an appropriate choice for therapy due to minimal resistance and propensity for collateral damage 1.

From the Research

Recommended Dose and Frequency of Nitrofurantoin (Macrobid) for UTI

• The recommended dose and frequency of Nitrofurantoin (Macrobid) for Urinary Tract Infection (UTI) is a 5-day course of nitrofurantoin, as stated in the study 2.
• Another study 3 suggests that nitrofurantoin monohydrate/macrocrystals (100 mg twice daily for 5-7 days) is an appropriate first-line therapy for uncomplicated cystitis.
• The pharmacokinetic characteristics of nitrofurantoin are discussed in the study 4, which highlights the importance of choosing an agent for treating uncomplicated UTIs based on its pharmacokinetic characteristics to optimize clinical benefit and minimize the risk of antibacterial resistance.
• The study 5 reports that nitrofurantoin is one of the most commonly prescribed antibiotic agents for uncomplicated UTIs, with 31.8% of visits resulting in a prescription for nitrofurantoin.
• The study 6 does not provide specific information on the dose and frequency of nitrofurantoin, but reports that 18.9% of participants received nitrofurantoin for their UTI, and that allergies to nitrofurantoin were not as common as allergies to other antibiotics, such as trimethoprim-sulfamethoxazole.

Key Points

• Nitrofurantoin is a recommended first-line treatment for uncomplicated UTIs 2, 3.
• The typical dose and frequency of nitrofurantoin is 100 mg twice daily for 5-7 days 3.
• Nitrofurantoin is one of the most commonly prescribed antibiotic agents for uncomplicated UTIs 5.
• Allergies to nitrofurantoin are relatively less common compared to other antibiotics 6.