Competitively inhibits 5-alpha reductase type II enzyme, blocking conversion of testosterone to dihydrotestosterone (DHT) in the prostate. DHT is the primary androgen driving prostatic hyperplasia. Reduces prostate size without affecting libido.
At a glance
Class
5-Alpha Reductase Inhibitor
Storage
Store at room temperature below 30°C; handle with gloves if pregnant women present
Dosing
Used for benign prostatic hyperplasia (BPH) in intact male dogs when castration
Feline prostatic disease is extremely rare
Educational reference only
This information is provided for educational purposes and is not a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a qualified veterinarian before administering any medication to your pet.
Find a vet near you →Safety
Prostate size by ultrasound at 8–12 weeksClinical signs (straining, hematuria)Hepatic enzymes periodically
Educational reference only
This information is provided for educational purposes and is not a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a qualified veterinarian before administering any medication to your pet.
Find a vet near you →Interactions
No documented interactions.
FAQs
Frequently asked questions
›What is Finasteride?
Finasteride is a 5-alpha reductase inhibitor used in pets. Competitively inhibits 5-alpha reductase type II enzyme, blocking conversion of testosterone to dihydrotestosterone (DHT) in the prostate. DHT is the primary androgen driving prostatic hyperplasia. Reduces prostate size without affecting libido.
›What is Finasteride used for in pets?
Finasteride is used in veterinary medicine for: Used for benign prostatic hyperplasia (BPH) in intact male dogs when castration ; Feline prostatic disease is extremely rare.
›What is the Finasteride dose for dogs?
For dogs, Finasteride is typically dosed as follows — Used for benign prostatic hyperplasia (BPH) in intact male dogs when castration : 0.1–0.5 mg/kg PO q24h. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›What is the Finasteride dose for cats?
For cats, Finasteride is typically dosed as follows — Feline prostatic disease is extremely rare: undefined undefined N/A N/A. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›Does Finasteride need a prescription?
Yes. Finasteride is a prescription medication and should only be administered under veterinary supervision.
Educational reference only
This information is provided for educational purposes and is not a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a qualified veterinarian before administering any medication to your pet.
Find a vet near you →References
References
The PetCare.AI drug reference is built from 13 authoritative sources cited across 580 drug monographs.
Textbooks & handbooks — 5
- Plumb's Veterinary Drug Handbook
- Withrow & MacEwen's Small Animal Clinical Oncology
- Merck Veterinary Manual
- NRC Nutrient Requirements of Dogs and Cats
- Veterinary Pharmacology and Therapeutics (Riviere & Papich)
Clinical guidelines & consensus — 4
- ASPCA Animal Poison Control Center Guidelines
- AAHA Diabetes Management Guidelines
- ASPCA Poison Control Guidelines
- RECOVER CPR Guidelines
Journals & peer-reviewed studies — 2
- EPIC Study (J Vet Intern Med 2016)
- JVIM FAT CAT Study
Regulatory & approvals — 1
- CDSCO Veterinary Drug Approval Registry (1969–2026)
Databases — 1
- Washington State University VCPL MDR1 Database