ExoticRx · exoticrx.com/drugs/phenoxybenzamine-ophthalmic
US brand names:Compounded Phenoxybenzamine Ophthalmic
Irreversible alpha-adrenergic antagonist that causes smooth muscle relaxation of the iris dilator, preventing miosis. Used to facilitate mydriasis in heavily pigmented irises.
Must be compounded. Used pre-operatively for cataract surgery in dogs with dark irises. Irreversible binding — effects last 24-48 hours. Local irritation possible.
Species references:All Dog (Domestic) drugs
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| Species | Route | Dose | Frequency | Evidence | Source |
|---|---|---|---|---|---|
| Dog (Domestic) | Ophthalmic | Compounded | 1 drop q8h starting 24h before surgery | Moderate | Gelatt KN, Veterinary Ophthalmology, 6th Ed |
| Dog (Domestic) | Ophthalmic | Combined with tropicamide/phenylephrine protocol for maximum dilation | 1 drop pre-operatively, repeat if needed | Moderate | Gelatt KN, Veterinary Ophthalmology, 6th Ed |
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