From the Research
Nitrofurantoin (Macrobid) is generally considered safe during the first trimester of pregnancy, but its use should be carefully weighed against potential risks and benefits, particularly in light of recent evidence suggesting an increased risk of serious cutaneous adverse drug reactions 1.
Key Considerations
- The evidence regarding an association between nitrofurantoin and birth defects is mixed, but it is still considered appropriate for use in the first trimester when no other suitable alternative antibiotics are available 2.
- A large population-based retrospective cohort study found no association between exposure to nitrofurantoin during the first trimester and major malformations 3.
- Nitrofurantoin is commonly prescribed to treat urinary tract infections in pregnant women and is classified as FDA Pregnancy Category B, indicating that animal studies have not shown risk to the fetus and there are no adequate studies in pregnant women showing adverse effects.
- The typical dosage is 100 mg twice daily for 5-7 days for uncomplicated UTIs.
- However, nitrofurantoin should be avoided near term (38-42 weeks) as it may cause hemolytic anemia in the newborn due to immature enzyme systems.
- It's also contraindicated in women with G6PD deficiency or renal insufficiency.
- Always take the full course of antibiotics as prescribed, even if symptoms improve, and maintain adequate hydration while taking this medication.
- Any unusual symptoms should prompt immediate consultation with your healthcare provider.
Recent Evidence
- A 2024 study found that nitrofurantoin is associated with an increased risk of serious cutaneous adverse drug reactions, with an adjusted odds ratio of 2.2 (95% CI, 2.1-2.4) compared to macrolides 1.
- Another study found that preferential use of nitrofurantoin over fluoroquinolones for acute uncomplicated cystitis was associated with a reduction in fluoroquinolone use and a stabilization in fluoroquinolone-resistant E. coli 4.