effects do antibiotics have on neuromuscular blockade?
Many antibiotics interact with neuromuscular
transmis-sion, enhancing the effect of neuromuscular muscle relaxants.
The aminoglycosides enhance nondepolarizing
neuro-muscular blockade by decreasing nerve terminal release of acetylcholine,
a magnesium-like effect. Additionally, aminoglycosides decrease the sensitivity
of the acetyl-choline receptor to acetylcholine. Aminoglycosides may augment
depolarizing neuromuscular blockade; however, this is less well studied.
Nonaminoglycoside antibiotics also augment
neuro-muscular blockade. Polymixin B augments blockade by decreasing
acetylcholine release from nerve terminals and by decreasing endplate ion
channel conductance. A local anesthetic-like effect may decrease the action
Both depolarizing and
nondepolarizing neuromuscular blockades are affected. Clindamycin and
lincomycin both enhance nondepolarizing neuromuscular blockade. They exert a
nonmagnesium-like, prejunctional effect. Clindamycin but not lincomycin has a
local anesthetic-like effect as well. The tetracyclines exert a pre-junctional
effect, increasing sensitivity to nondepolarizing neuromuscular blockade but
not to succinylcholine.