Timolol Maleate

Caution recommended due to possible atrioventricular conduction disturbances, left ventricular failure, and hypotension. Coadministration should be avoided in patients with impaired cardiac function.

Beta-blockers may exacerbate rebound hypertension following clonidine withdrawal; staggered discontinuation required.

Concomitant use may have additive effects in prolonging atrioventricular conduction time. Caution should be used due to possible atrioventricular conduction disturbances.

Left ventricular failure and AV conduction disturbances reported with concomitant use; additive effects in prolonging AV conduction time.

Patients may be unresponsive to usual doses of epinephrine used to treat anaphylactic reactions.

Hypotension more likely to occur when dihydropyridine calcium antagonist is added to beta-blocker therapy.

Potentiated systemic beta-blockade (decreased heart rate, depression) has been reported during combined treatment with this CYP2D6 inhibitor and timolol.

Close observation recommended when timolol is administered with reserpine due to possible additive effects and production of hypotension and/or marked bradycardia, which may result in vertigo, syncope, or postural hypotension.

Left ventricular failure and AV conduction disturbances reported with concomitant use; additive effects in prolonging AV conduction time.

Potential additive effect on systemic effects of carbonic anhydrase inhibition. Concomitant administration is not recommended.

Potential additive effects of beta-blockade, both systemic and on intraocular pressure. Concomitant use of two topical beta-adrenergic blocking agents is not recommended.

Blunting of the antihypertensive effect of timolol; patients should be carefully observed to confirm desired therapeutic effect.

High-dose salicylate therapy may cause acid-base and electrolyte disturbances leading to toxicity when combined with dorzolamide.

Drug Interactions Although Timolol Maleate Ophthalmic Solution used alone has little or no effect on pupil size, mydriasis resulting from concomitant therapy with Timolol Maleate Ophthalmic Solution and epinephrine has been reported occasionally. Beta-adrenergic blocking agents: Patients who are receiving a beta-adrenergic blocking agent orally and Timolol Maleate Ophthalmic Solution should be observed for potential additive effects of beta-blockade, both systemic and on intraocular pressure. Calcium antagonists: Caution should be used in the coadministration of beta-adrenergic blocking agents, such as Timolol Maleate Ophthalmic Solution, and oral or intravenous calcium antagonists because of possible atrioventricular conduction disturbances, left ventricular failure, and hypotension.

7 DRUG INTERACTIONS Potential additive effect of oral carbonic anhydrase inhibitor with dorzolamide hydrochloride and timolol maleate ophthalmic solution. (7.7) 7.1 Oral Carbonic Anhydrase Inhibitors There is a potential for an additive effect on the known systemic effects of carbonic anhydrase inhibition in patients receiving an oral carbonic anhydrase inhibitor and dorzolamide hydrochloride and timolol maleate ophthalmic solution. The concomitant administration of dorzolamide hydrochloride-timolol maleate ophthalmic solution and oral carbonic anhydrase inhibitors is not recommended.