Tetrahydrozoline
Allergy · OTC
Trade namesVisine Original, Murine Plus
Drug classImidazoline decongestant
Strength0.05%
AvailabilityOTC
Mechanism of actionAlpha-adrenergic agonist; conjunctival vasoconstriction.
Indication / reason for useShort-term relief of conjunctival redness from minor irritation.
Usual adult dosing1-2 drops up to 4×/day, ≤72 h.
PreservativeBAK
Contact lensesRemove lenses before use.
Common / important adverse effectsRebound hyperemia with chronic use, stinging, mydriasis, systemic effects (CNS depression) if ingested, keep away from children.
Contraindications & cautionsNarrow angles; caution with cardiovascular disease, hyperthyroidism, MAOIs.
Pregnancy / lactationAvoid routine use.
Practice notesIngestion by a child is a poison-control emergency.
Chair-side reference only. Dosing, contraindications and pregnancy guidance here are not exhaustive. Confirm against the current prescribing information and the patient’s full history before prescribing or advising.