Comparative Pharmacology
Head-to-head clinical analysis: BREVIBLOC DOUBLE STRENGTH IN PLASTIC CONTAINER versus DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: BREVIBLOC DOUBLE STRENGTH IN PLASTIC CONTAINER versus DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE.
BREVIBLOC DOUBLE STRENGTH IN PLASTIC CONTAINER vs DORZOLAMIDE HYDROCHLORIDE AND TIMOLOL MALEATE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Selective beta-1 adrenergic receptor antagonist; reduces heart rate, myocardial contractility, and blood pressure by blocking catecholamine effects at beta-1 receptors.
Dorzolamide is a carbonic anhydrase inhibitor that reduces aqueous humor secretion by inhibiting carbonic anhydrase in the ciliary processes. Timolol is a non-selective beta-adrenergic receptor antagonist that reduces aqueous humor production by blocking beta-2 adrenergic receptors in the ciliary epithelium.
Intravenous: For stable patients, an initial loading dose of 500 mcg/kg/min over 1 minute followed by a maintenance infusion of 50 mcg/kg/min for 4 minutes; if response is inadequate, increase maintenance infusion to 100 mcg/kg/min and repeat loading dose after 10 minutes. Titrate in 50 mcg/kg/min increments up to 200 mcg/kg/min. For intraoperative and postoperative use, see full prescribing information.
One drop of the fixed combination (dorzolamide 22.26 mg/mL, timolol 6.83 mg/mL) in the affected eye(s) every 12 hours.
None Documented
None Documented
Terminal elimination half-life is approximately 9 minutes (range 8–10 minutes). Clinically, the half-life is consistent with rapid offset of effect upon discontinuation; steady state is achieved within 30 minutes of continuous infusion.
Dorzolamide: ~4 months but accumulates in RBCs; terminal half-life ~4-5 months due to binding to carbonic anhydrase. Timolol: ~4-6 hours.
Primarily metabolized by red blood cell esterases; <1% excreted unchanged in urine. Elimination is not dependent on renal or hepatic function.
Dorzolamide: primarily renal (approx. 80% unchanged), with minor biliary/fecal elimination. Timolol: renal (15-20% unchanged) and extensive hepatic metabolism with fecal excretion.
Category C
Category A/B
Beta-Blocker
Beta-Blocker