What is Clemastine used for?

Clemastine is indicated for: Allergic dermatitis, allergic rhinitis, Atopic dermatitis, pruritus.

Which species have cited Clemastine dosing data?

Clemastine dosing in the ExoticRx formulary covers 2 species: Cat (Domestic), Dog (Domestic).

Is Clemastine a controlled substance?

Clemastine is not federally scheduled in the US. Controlled-drug status differs by country — verify your local rules.

Clemastine

US brand names:Tavist, Dayhist

Calculate dosage

Sourced from published veterinary references. Awaiting credentialed clinical reviewer — our editorial process.

Clemastine is dosed at 0.05–0.1 mg/kg PO q12h in dogs, per Miller WH, Scott DW, Wellington JR. A clinical-trial on the efficacy of clemastine in the management of allergic pruritus in dogs. Canadian Veterinary Journal-Revue Veterinaire Canadienne. 1993;34:25-27. PMID: 17424141 — Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.307 (2026-08-01).. Verify against current literature before clinical use.

Drug Class

Respiratory

Routes

Indications

Allergic dermatitisallergic rhinitisAtopic dermatitispruritus

Mechanism of Action

Competitive H1 histamine receptor antagonist that blocks histamine-mediated allergic responses including pruritus, urticaria, and rhinitis.

Side effects & warnings

Sedation is common. Anticholinergic effects (dry mouth, urinary retention). May be more effective than diphenhydramine for canine atopic dermatitis.

Evidence levels across 2 dose rules

Moderate×1Weak×1

Each ExoticRx dose rule is graded by the strength of its primary evidence — see the editorial process.

Backed by 2 published sources

· Miller WH, Scott DW, Wellington JR. A clinical-trial on the efficacy of clemastine in the management of allergic pruritus in dogs. Canadian Veterinary Journal-Revue Veterinaire Canadienne. 1993;34:25-27. PMID: 17424141 — Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.307 (2026-08-01).
· Miller WH, Scott DW. Clemastine fumarate as an antipruritic agent in pruritic cats - results of an open clinical-trial. Canadian Veterinary Journal-Revue Veterinaire Canadienne. 1994;35:502-504. — Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.307 (2026-08-01).

Sample dosing (2 of 2 cited rules)

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	0.05–0.1 mg/kg	q12h	Moderate	Miller WH, Scott DW, Wellington JR. A clinical-trial on the efficacy of clemastine in the management of allergic pruritus in dogs. Canadian Veterinary Journal-Revue Veterinaire Canadienne. 1993;34:25-27. PMID: 17424141 — Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.307 (2026-08-01).
Cat (Domestic)	PO	0.34–0.67 mg per cat	q12h	Weak	Miller WH, Scott DW. Clemastine fumarate as an antipruritic agent in pruritic cats - results of an open clinical-trial. Canadian Veterinary Journal-Revue Veterinaire Canadienne. 1994;35:502-504. — Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.307 (2026-08-01).

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