Clemastine
Also known as: Tavist, Tavist Allergy, Dayhist-1, Agasten, Aller-Eze, Antihist-1, Clamist, Contac 12 Hour Allergy, Tavegil, Tavegyl, Meclastin
Clemastine is an antihistamine used to help manage allergies. * **Symptom Relief:** Understand that antihistamines may be useful for the symptomatic relief of allergic signs, but they are **not a cure** for the underlying disease. * **Side Effects:** May cause mild sleepiness or, conversely, unexpected hyperactivity in some pets. Dry mouth is also possible. * **Cats:** Watch for diarrhea, which is the most commonly reported side effect in felines. * **Administration:** Give exactly as prescribed. Do not increase the dose without consulting your veterinarian.
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
What it is used for
- Antihistamine
- Antihistamine
- Atopy
- Allergic conditions (Historical dosing - Efficacy doubtful)
How it is given
Possible side effects
- Sedation (dogs)
- Paradoxical hyperactivity (dogs)
- Anticholinergic effects: dry mucous membranes, tachycardia, urinary retention
- Diarrhea (cats)
- Fixed drug reaction (cats - rare)
Cautions & contraindications
- Known hypersensitivity to clemastine
- Use with caution in patients with prostatic hypertrophy, bladder neck obstruction, severe cardiac failure, angle-closure glaucoma, or pyeloduodenal obstruction. Antihistamines should be discontinued 3-7 days before intradermal skin testing to prevent false-negative wheal and flare responses. Use with caution in pregnant or nursing animals, especially with newborns, as the drug enters maternal milk.
Drug interactions
- CNS Depressant Medications (e.g., barbiturates, tranquilizers): Additive CNS depression may occur.
- Monoamine Oxidase Inhibitors (e.g., furazolidone, amitraz, selegiline): May intensify the anticholinergic effects of clemastine.
- CNS Depressants (e.g., phenobarbital, gabapentin, opioids): Additive CNS depression and sedation
- Anticholinergic drugs: Additive anticholinergic effects (dry mouth, urinary retention)
Frequently asked questions
What is Clemastine used for in pets?
Clemastine is an antihistamine used to help manage allergies. * **Symptom Relief:** Understand that antihistamines may be useful for the symptomatic relief of allergic signs, but they are **not a cure** for the underlying disease. * **Side Effects:** May cause mild sleepiness or, conversely, unexpected hyperactivity in some pets. Dry mouth is also possible. * **Cats:** Watch for diarrhea, which is the most commonly reported side effect in felines. * **Administration:** Give exactly as prescribed. Do not increase the dose without consulting your veterinarian.
Is Clemastine safe for my pet?
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
This article is for general education and is not a substitute for professional veterinary advice. If your pet is unwell, please consult a veterinarian.
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