ExoticRx · exoticrx.com/drugs/finasteride
US brand names:Proscar, Propecia
Finasteride is dosed at 5 mg/kg PO q24h in ferrets, per Rosenthal K. Endocrine disorders of ferrets: insulinoma and adrenal gland disease. Annu Waltham/OSU Symp Treat Small Anim Dis: Exotics Proc 21st; 1997:35-38. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.949 — Carpenter's Exotic Animal Formulary 6th ed, Table 11.8 (Endocrine and Reproductive Disease Agents Used in Ferrets). The copy held is an ebook conversion with no printed page numbers, so the table — not the page — is the citable location. — SOURCE EDITION: Carpenter's Exotic Animal Formulary — ISBN 9780323833929, https://openlibrary.org/isbn/9780323833929. Verify against current literature before clinical use.
Inhibits 5-alpha reductase type II, blocking conversion of testosterone to dihydrotestosterone (DHT). Reduces prostate size.
Used for benign prostatic hyperplasia in dogs. Teratogenic — do not handle crushed tablets during pregnancy. Effects take weeks. Does not affect libido.
Species references:All Dog (Domestic) drugsAll Ferret drugs
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A dog/cat sample is shown here. Cited dosing for all 2 species — reptiles, birds, pocket pets, livestock, and equine — is free on the per-species pages above. Pro adds the weight-based calculator for every species.
| Species | Route | Dose | Frequency | Evidence | Source |
|---|---|---|---|---|---|
| Dog (Domestic) | PO | 0.1–0.5 mg/kg | q24h | Moderate | Sirinarumitr K, Johnston SD, Kustritz MVR, Johnston GR, Sarkar DK, Memon MA. Effects of finasteride on size of the prostate gland and semen quality in dogs with benign prostatic hypertrophy. J Am Vet Med Assoc. 2001;218(8):1275-1280. doi:10.2460/javma.2001.218.1275; Lima CB, Angrimani DSR, Flores RB, Vannucchi CI. Endocrine, prostatic vascular, and proapoptotic changes in dogs with benign prostatic hyperplasia treated medically or surgically. Domest Anim Endocrin. 2021;75:106601. doi:10.1016/j.domaniend.2020.106601 — Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.552 (2026-08-01). — Plumb's 10th ed (held) printed p.524, Finasteride monograph; page located 2026-08-05 from the book's own running heads, verified to name the drug in its body text. — SOURCE EDITION: Plumb's Veterinary Drug Handbook — ISBN 9781394172207, https://openlibrary.org/isbn/9781394172207 |
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View PlansSource citations and evidence levels available on the live page. Reference only — verify against current literature before clinical use.