What dutasteride does to sperm, semen and testosterone, and what to do if you want kids.
Find Your ProtocolIt can lower it somewhat. In the study on the FDA label, healthy men aged 18 to 52 took 0.5mg dutasteride for a year. On average, compared with placebo:
Sperm concentration and shape didn’t change, and the average results stayed in the normal range. Two men had much bigger drops, which partly recovered after stopping. Six months after stopping, the group’s average sperm count was still 23% below where it started. What this means for any one man’s fertility isn’t known.
Many men do. The average changes in the label study stayed within the normal range. But if you’re actively trying, or your fertility is already borderline, don’t guess. Tell your physician, and consider a semen analysis before you start so you have a baseline.
Lower semen volume is one of the more common things men notice on dutasteride. The label study showed a 26% average drop. It’s usually a volume change, not a sign that something is wrong, but tell your physician if it bothers you.
A small amount of dutasteride ends up in semen. According to the FDA label, even in a worst case it’s about 100 times lower than the levels that caused problems in animal studies, so it isn’t expected to affect a pregnancy. Women who are or may become pregnant still shouldn’t handle the softgels, because dutasteride can be absorbed through the skin. Full side effects →
No. Dutasteride blocks the enzyme that turns testosterone into DHT. Less testosterone gets converted, so testosterone usually goes up a little, typically staying in the normal range. The drop in DHT is what protects your hair.
Most men don’t notice any change. A small percentage report lower sex drive or erection problems, usually in the first months. The FDA label numbers are on our side effects page. If you notice something, tell your physician; options include lowering the dose or stopping.
Many men do. Testosterone therapy raises DHT too, which can speed up hair loss in men who are prone to it, so a DHT blocker is a common pairing. Keep in mind that TRT itself lowers sperm production. Fertility on TRT, including medications like hCG, is managed by the doctor who prescribes your TRT. We don’t prescribe TRT. Make sure both doctors know everything you take. More dutasteride questions →
Tell your physician before you start or as soon as you’re planning. Your options include staying on your dose, lowering it, or pausing. Dutasteride stays in your body for months (its half-life is about 5 weeks), so plan ahead rather than stopping the week you start trying.
The label study used 0.5mg. There’s much less data on sperm and semen at 1.5mg or 2.5mg. If fertility matters to you right now, that’s worth weighing with your physician when choosing a dose. How to choose your dose →
It can. Finasteride also lowers semen volume in studies, and there are reports of lower sperm counts in some men, especially those whose counts were already low. Neither drug is a form of birth control.