DHT blockers: what they do and who they help

Hair thinning or an enlarged prostate? DHT blockers often show up in both conversations. DHT (dihydrotestosterone) is a male hormone that can shrink hair follicles and drive prostate growth. Blocking DHT can slow hair loss and ease urinary symptoms from benign prostatic hyperplasia (BPH).

This page gives clear, practical info: the common prescription drugs, natural and topical choices, what to expect, and safety tips so you can ask smarter questions at your next doctor visit.

Prescription DHT blockers you’ll likely hear about

Finasteride and dutasteride are the two main prescription DHT blockers. Finasteride (often 1 mg for hair loss) lowers DHT by blocking the enzyme that converts testosterone into DHT. Dutasteride blocks the same enzyme but more strongly. Both can slow hair thinning, and in many people they help regrow some hair over months.

If you’re using them for BPH, doses and monitoring differ. These drugs can lower PSA (a prostate cancer screening marker), so tell your doctor before testing. Side effects can include reduced libido, erectile issues, and mood changes in a small number of users. Some effects stop after you stop the drug; others can linger for some people. Women who are pregnant or may become pregnant should avoid handling crushed or broken tablets.

Topical forms of finasteride are available in some places. They aim to cut systemic exposure while keeping the drug where it’s needed—on the scalp. Talk to your provider about options and prescriptions.

Natural and topical options people try

Saw palmetto is a popular herbal option. Some small studies show modest benefit, but evidence is weaker than for finasteride. Pumpkin seed oil, green tea extract, and supplements with zinc or biotin get mentioned a lot. They’re generally lower risk, but results vary and tend to be smaller.

Ketoconazole shampoo and caffeine shampoos act locally on the scalp. Ketoconazole has mild anti-androgen effects and can reduce scalp inflammation; using it a few times per week may help when combined with other treatments. Minoxidil (non-DHT) isn’t a DHT blocker but pairs well with them to boost results.

How long until you see change? Expect at least 3–6 months to notice slowing of hair loss, and up to a year for visible regrowth. If you stop treatment, benefits usually reverse within months.

Questions to ask your doctor: Which drug fits my goals (hair vs. prostate)? What side effects should I watch for? Do I need blood tests or PSA monitoring? Can I combine treatments safely?

If you’re thinking about trying a DHT blocker, start with a medical check and clear goals. Use trusted pharmacies, follow dosing, and track changes. Small, steady steps usually work best—don’t expect overnight fixes, but give treatments time and check in with your clinician if anything feels off.