Finasteride / Dutasteride
Oral 5-alpha-reductase inhibitors that lower DHT to slow hair loss and treat benign prostatic hyperplasia (BPH). Finasteride is selective while dutasteride blocks more of the enzyme.
- Half-life
- 6 h
- Out of system
- ~1.3 days
- Route
- Oral
- Level
- Intermediate
Short-acting — protocols usually dose daily. After the last dose, roughly 97% has cleared in ~1.3 days (five half-lives) — the window that matters for washouts, bloodwork and surgery.
What Finasteride / Dutasteride is used for
- Reduces DHT to slow or partially reverse pattern hair loss
- Shrinks the prostate and relieves urinary symptoms in BPH
- Convenient low-dose oral daily regimen
How it's typically used
Literature range: finasteride 1 mg orally daily for hair loss (higher for BPH), with dutasteride dosed lower, as reported in the research.
What to watch for
- Can cause sexual side effects including reduced libido and erectile dysfunction
- A minority report persistent symptoms after stopping (post-finasteride syndrome)
- Prescription 5-alpha-reductase inhibitors; use only under medical supervision
About Ancillaries (SERMs / AIs)
- What they are
- Support drugs — SERMs, aromatase inhibitors, and prolactin controls used to manage the side effects of androgen use or to restart natural production afterwards.
- How they're run
- Oral tablets, dosed against bloodwork rather than on a fixed schedule.
- What to watch
- These are only meaningful with labs in hand. Crushing oestrogen with an AI wrecks joints, libido, and lipids just as thoroughly as having too much of it.
Full guide
Finasteride and Dutasteride: A Tracking Guide for 5-Alpha-Reductase Inhibitors
A balanced, harm-reduction look at finasteride and dutasteride, how they cut DHT for hair loss, and the honest tradeoffs including post-finasteride syndrome.
Other ancillaries (serms / ais)
Peptid AI is an educational and self-tracking tool — not a medical service, and not a vendor. Nothing here is medical advice, a prescription, or an endorsement. Doses reflect what is commonly reported in research literature; they are not recommendations. Many compounds listed are experimental, not approved for human use, and/or controlled substances that are illegal to possess without a prescription in many countries. Always consult a qualified physician before starting, changing, or stopping any protocol.