Furosemide (Lasix) and finasteride (Proscar) are both prescription medications, but they serve different purposes and belong to different drug classes. Furosemide is a loop diuretic, commonly known as a water pill, used to relieve swelling due to heart failure, liver problems, or kidney problems, and to lower blood pressure. It works by making you urinate more to get rid of extra water and electrolytes. On the other hand, finasteride is a 5-alpha reductase inhibitor used to treat benign prostatic hyperplasia (BPH) in men, which helps relieve urinary symptoms and reduces the need for prostate surgery. It works by blocking the conversion of testosterone to dihydrotestosterone (DHT), which causes the prostate to shrink. Furosemide starts working within an hour, while finasteride can take up to six months to show effects. Both medications are available as a lower-cost generics. Additionally, furosemide can cause frequent urination and dizziness, whereas finasteride may lead to sexual side effects like the inability to have an erection and lower sex drive. Pregnant women should avoid handling crushed or broken finasteride tablets due to the risk of harm to the unborn baby.