Drug Interactions between Cortisporin Otic and succinylcholine

MONITOR: Aminoglycosides possess neuromuscular blocking activity, which may be additive with that of depolarizing and nondepolarizing muscle relaxants, potentially resulting in severe and/or prolonged respiratory depression during concomitant use. Aminoglycosides inhibit the release of acetylcholine at neuromuscular junctions by interfering with calcium influx. They also appear to decrease the sensitivity of postsynaptic membrane to acetylcholine. The interaction has been observed with various routes of aminoglycoside administration including oral, intramuscular, intravenous, intraperitoneal, esophageal, intraluminal, intradural, and beneath skin flaps. Respiratory paralysis and fatalities have been reported. Patients at increased risk include those with renal impairment and/or hypocalcemia.

MANAGEMENT: Topically applied aminoglycosides may be systemically absorbed, and significant absorption could occur in certain circumstances (e.g., application to burnt or broken skin; use of large quantities or on large areas for prolonged periods). Clinicians should be aware of the potential for interaction if neuromuscular blockers are used in patients who have been treated extensively with topical aminoglycosides. Vital signs should be closely monitored, and ventilatory support should be readily available in case of respiratory arrest. Treatment with anticholinesterases and calcium may not always be effective in reversing the neuromuscular blockade caused by these agents.