The important points
- Finasteride 1 mg is used for male androgenetic alopecia in suitable adults.
- Dutasteride is licensed for benign prostate enlargement rather than hair loss.
- Any dutasteride discussion for hair loss is off-label and never an automatic prescription.
- Both require an individual benefit-risk discussion and appropriate follow-up.
Why they are compared
Both medicines inhibit 5-alpha reductase and reduce formation of DHT, which is involved in androgenetic hair loss. Dutasteride inhibits more than one form of the enzyme, but pharmacological potency alone does not establish that it is the correct or licensed choice for an individual patient.
The licensing difference matters
Finasteride 1 mg has a licensed hair-loss indication for suitable men. Dutasteride 0.5 mg is authorised for benign prostate enlargement. Prescribing outside the licensed indication requires a specific clinical rationale, transparent explanation and individual consent.
| Point | Clinical meaning |
|---|---|
| Hair-loss licence | Finasteride 1 mg: licensed for suitable male androgenetic alopecia. Dutasteride: not licensed for hair loss. |
| Enzyme action | Finasteride mainly inhibits type II 5-alpha reductase; dutasteride inhibits type I and II. |
| Routine route | Finasteride may be considered after assessment. Dutasteride requires an explicit off-label decision. |
| Repeat requests | Only established, unchanged treatment with evidence can use the focused repeat route. |
Safety and follow-up
The clinician reviews sexual adverse effects, fertility and pregnancy-handling precautions, mood symptoms, liver history and other medicines. A repeat request is suitable only when treatment has already been established, remains unchanged and is supported by named evidence.
Dr Ben Harry Clegg
General practitioner · Málaga registration 292911940 · Nerja Medical Center NICA 55712
Official sources and connected clinical guidance
Medical information and product instructions can change. Follow the leaflet supplied with the exact medicine and the individual plan agreed with your clinician.
Do you need an individual hair-loss assessment?
Discuss the pattern, previous treatment, medical history and the safest next step with an English-speaking doctor.