Dorzolamide / timolol
Glaucoma · Rx
Trade namesCosopt, Cosopt PF
Drug classFixed combination, CAI + beta-blocker
StrengthDorzolamide 2% + timolol 0.5%
AvailabilityRx
Mechanism of actionTwo aqueous-suppressants with additive effect; fewer bottles and less total preservative than separate agents.
Indication / reason for useOpen-angle glaucoma / ocular hypertension inadequately controlled on one agent.
Usual adult dosing1 drop in the affected eye(s) twice daily.
PreservativeBAK 0.0075% (Cosopt PF is preservative-free single-use vials) , a preservative-free option exists
Contact lensesRemove lenses; reinsert after 15 minutes. Prefer Cosopt PF for lens wearers / ocular surface disease.
Common / important adverse effectsCombined profile: taste disturbance, stinging, plus systemic beta-blocker effects.
Contraindications & cautionsReactive airway disease, bradycardia/AV block/heart failure (timolol); severe renal impairment, sulfonamide allergy, compromised endothelium (dorzolamide).
Pregnancy / lactationAvoid where possible.
Practice notesScreen for both beta-blocker and CAI contraindications before prescribing a combination.
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.