From the Guidelines
Macrobid (nitrofurantoin) is effective for treating nitrite-positive urinary tract infections (UTIs), with a recommended dosage of 100 mg taken orally twice daily for 5 days, as supported by the most recent guidelines from the American College of Physicians 1. The medication works particularly well against common UTI-causing bacteria like E. coli, which often produce nitrites in urine. Some key points to consider when prescribing Macrobid include:
- The medication concentrates in the urinary tract rather than in the bloodstream, making it specifically effective for bladder infections.
- Macrobid is not appropriate for kidney infections, for patients with poor kidney function (creatinine clearance <30 mL/min), or during late pregnancy.
- Common side effects include nausea, which can be reduced by taking the medication with food.
- It's essential to complete the full course of treatment even if symptoms improve before finishing the medication.
- Patients should drink plenty of water while taking Macrobid and should contact their healthcare provider if symptoms worsen or don't improve within 3 days. According to the guidelines, nitrofurantoin monohydrate/macrocrystals (100 mg twice daily for 5 days) is an appropriate choice for therapy due to minimal resistance and propensity for collateral damage, with efficacy comparable to 3 days of trimethoprim-sulfamethoxazole 1. Additionally, studies have shown that nitrofurantoin has a clinical cure rate of 88% - 93% and a bacterial cure rate of 81% - 92% in treating acute uncomplicated cystitis 1. Overall, Macrobid is a suitable option for treating nitrite-positive UTIs, with its effectiveness and safety profile supported by recent guidelines and studies.
From the Research
Effectiveness of Macrobid for Nitrite-Positive UTI
- Macrobid (nitrofurantoin) is effective in treating uncomplicated urinary tract infections (UTIs), including those that are nitrite-positive 2, 3, 4, 5.
- Studies have shown that nitrofurantoin is active against common uropathogens, including Escherichia coli, Staphylococcus saprophyticus, and Enterococcus species 2, 4.
- A randomized controlled trial found that nitrofurantoin was significantly more effective than placebo in achieving bacteriological cure and symptomatic relief in women with uncomplicated UTIs 2.
- Another study compared the efficacy of nitrofurantoin with fosfomycin in women with uncomplicated lower UTIs and found that nitrofurantoin resulted in a significantly greater likelihood of clinical and microbiologic resolution at 28 days after therapy completion 5.
- Nitrofurantoin is also considered a valuable treatment option for UTIs in men, provided that systemic symptoms are absent 6.
Considerations for Use
- Nitrofurantoin is contraindicated in the last three months of pregnancy and in patients with renal impairment of any degree 4.
- The use of nitrofurantoin may be accompanied by adverse drug effects, including pulmonary reactions and polyneuropathy, which mainly occur with long-term use 4.
- Short-term nitrofurantoin therapy has been shown to be effective and well-tolerated, with a low frequency of adverse events 5.