ExoticRx · exoticrx.com/drugs/methenamine
US brand names:Mandelamine, Hiprex
Methenamine is dosed at 10–20 mg/kg PO q12h in dogs, per Greene CE. Infectious Diseases of the Dog and Cat. Elsevier Health Sciences; 2013. Distributed by John Wiley & Sons, Inc. doi:10.1016/c2014-0-03934-2 — Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.876 (2026-08-01).. Verify against current literature before clinical use.
Hydrolyzed to formaldehyde in acidic urine (pH < 5.5), which is bactericidal. Requires acidic urine pH for activity.
Ineffective if urine pH > 6.5. May need urinary acidifiers concurrently. GI irritation. Avoid in renal insufficiency. Avoid with sulfonamides (precipitate formation).
Species references:All Dog (Domestic) drugs
Each ExoticRx dose rule is graded by the strength of its primary evidence — see the editorial process.
A dog/cat sample is shown here. Cited dosing for all 1 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 | 10–20 mg/kg | q12h | Weak | Greene CE. Infectious Diseases of the Dog and Cat. Elsevier Health Sciences; 2013. Distributed by John Wiley & Sons, Inc. doi:10.1016/c2014-0-03934-2 — Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.876 (2026-08-01). |
Upgrade to Pro or Student to unlock the full dose ranges and frequency for every species. The drug's mechanism, warnings, indications, and cited sources are free to read.
View PlansSource citations and evidence levels available on the live page. Reference only — verify against current literature before clinical use.