Key takeaways
Nitrofurantoin (Macrobid) and Elmiron (pentosan) are both prescription medications, but they serve different purposes and belong to different drug classes. Nitrofurantoin is a nitrofuran antibiotic used to treat or prevent urinary tract infections (UTIs) by killing bacteria in the urinary tract. It is available in both brand and lower-cost generic forms. Common side effects include nausea, headache, and gas. On the other hand, Elmiron is a urinary analgesic used to relieve bladder pain and discomfort caused by bladder pain syndrome (interstitial cystitis). It is not the first-choice treatment for this condition and can take 3 to 6 months to start working. Elmiron does not have a generic version and can cause side effects like hair loss, nausea, and changes in vision. While Nitrofurantoin is taken with food to improve absorption and reduce stomach upset, Elmiron should be taken on an empty stomach to ensure effectiveness. Additionally, Elmiron carries a risk of causing bleeding and permanent eye damage, which are not associated with Nitrofurantoin.
