Drug Interaction Report

MONITOR: The antihypertensive effects of methoxyflurane and beta blockers may be additive. The combination may cause profound hypotension. Older anesthetics such as methoxyflurane have more severe circulatory depressant effects in the presence of beta-blockade.

MANAGEMENT: It is currently recommended that beta blocker therapy not be routinely withdrawn prior to surgery. However, in general, patients taking beta blockers should not be anaesthetized with methoxyflurane. Instead, an anesthetic with minimal negative inotropic activity may be considered. If methoxyflurane must be used, beta blocker therapy should be withdrawn gradually and generally completed 24 to 48 hours before anesthesia.

GENERALLY AVOID: Alcohol may potentiate some of the pharmacologic effects of central nervous system (CNS)-active agents. Use in combination may result in additive CNS depression and/or impairment of judgment, thinking, and psychomotor skills.

MANAGEMENT: Patients receiving CNS-active agents should be advised to avoid or limit consumption of alcohol. Ambulatory patients should be counseled against driving, operating machinery, or engaging in potentially hazardous activities requiring mental alertness and motor coordination until they know how these agents affect them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities.