Interaksi Betaksolol dan Epinefrin

…concomitantly receiving any of the following drugs should be observed carefully for the development of cardiac arrhythmias [see Warnings and Precautions (5.6) and Adverse Reactions (6) ]. β-blockers, such as propranolol Cyclopropane or halogenated hydrocarbon anesthetics, such as halothane Antihistamines Thyroid hormones Diuretics Cardiac glycosides, such as digitalis…

Epinephrine may antagonize the neuronal blockade produced by guanethidine resulting in decreased antihypertensive effect and requiring increased dosage of the latter.

• Drugs that potentiate the effects of epinephrine include sympathomimetics, beta blockers, tricyclic antidepressants, MAO inhibitors, COMT inhibitors, clonidine, doxapram, oxytocin, levothyroxine sodium, and certain antihistamines.

• Drugs that increase the arrhythmogenic potential of epinephrine include beta blockers, cyclopropane and halogenated hydrocarbon anesthetics, quinidine, antihistamines, exogenous thyroid hormones, diuretics, and cardiac glycosides.

Drugs antagonizing pressor effects of epinephrine α-blockers, such as phentolamine Vasodilators, such as nitrates Diuretics Antihypertensives Ergot alkaloids Drugs potentiating pressor effects of epinephrine • Sympathomimetics • β-blockers, such as propranolol • Tricyclic anti-depressants • Monoamine oxidase (MAO) inhibitors • Catechol-O-methyl transferase (COMT)…

Risk of Anaphylactic Reaction Although it is known that patients on beta-blockers may be refractory to epinephrine in the treatment of anaphylactic shock, beta-blockers can, in addition, interfere with the modulation of allergic reaction and lead to an increased severity and/or frequency of attacks.

Such patients may be unresponsive to the usual doses of epinephrine used to treat allergic reaction.

Since β 1 -selectivity is not absolute and is inversely related to dose, the lowest possible dose of betaxolol should be used (5 to 10 mg once daily) and a bronchodilator should be made available.