ExoticRx · exoticrx.com/drugs/phenylephrine-ophthalmic
Mydfrin, Neo-Synephrine Ophthalmic
Alpha-1 adrenergic agonist causing contraction of iris dilator muscle (mydriasis) without cycloplegia. Also causes conjunctival vasoconstriction.
10% concentration can cause systemic hypertension — use 2.5% in small animals. Mydriasis without cycloplegia (pupil still accommodates). Avoid in narrow-angle glaucoma.
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| Species | Route | Dose | Frequency | Evidence | Source |
|---|---|---|---|---|---|
| Dog (Domestic) | TOPICAL (ophthalmic) | 0 1 drop 2.5% per eye | PRN for exam or q6-8h therapeutic | Moderate | Plumb's Veterinary Drug Handbook, 9th Ed |
| Cat (Domestic) | TOPICAL (ophthalmic) | 0 1 drop 2.5% per eye | PRN for exam or q6-8h | Moderate | Plumb's Veterinary Drug Handbook, 9th Ed |
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