Dutasteride: What It Is, How It Works, and How It Compares to Finasteride

When you hear dutasteride, a 5-alpha reductase inhibitor used to treat enlarged prostate and male pattern hair loss. Also known as Avodart, it works by blocking the enzyme that turns testosterone into DHT—the main culprit behind both hair thinning and prostate growth. Unlike finasteride, which only blocks one type of this enzyme, dutasteride shuts down two, making it more powerful at lowering DHT levels across the body.

This difference matters. If you’ve tried finasteride and didn’t see results, or if your prostate is significantly enlarged, dutasteride might be the next step. It’s not just a stronger version—it’s a different tool. Studies show it reduces DHT by over 90%, compared to about 70% with finasteride. That extra drop can mean slower hair loss, better regrowth, and improved urinary flow for men with BPH. But with more power comes more potential side effects: lower libido, erectile issues, and breast tenderness are possible, though not guaranteed. The key is knowing your goals and risks before starting.

Many people compare finasteride, a well-known drug for hair loss and prostate issues, often sold as Propecia or Proscar to dutasteride because they’re used for similar reasons. But they’re not interchangeable. Finasteride is FDA-approved for hair loss; dutasteride isn’t—yet it’s still commonly prescribed off-label for it. Some doctors prefer finasteride for younger men worried about sexual side effects, while others choose dutasteride for men with larger prostates or faster hair loss. Then there’s BPH, benign prostatic hyperplasia, a non-cancerous enlargement of the prostate that affects most men over 50. Dutasteride is one of the few drugs proven to shrink the prostate over time, not just ease symptoms. And for those exploring hair loss treatment, options that target the root cause rather than just covering thinning, dutasteride sits near the top of the list—alongside minoxidil, spironolactone, and low-level laser therapy.

You’ll find posts here that break down exactly how dutasteride stacks up against finasteride in real-world use—cost, side effects, how long it takes to work, and whether switching makes sense. You’ll also see how it fits into broader discussions about prostate health, medication safety, and what happens when you stop taking it. No fluff. Just clear comparisons, patient experiences, and what your doctor might not tell you. Whether you’re considering starting, already on it, or just researching options, this collection gives you the facts you need to make a smart decision.