What effects do antibiotics have on neuromuscular blockade?

What 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 potential of muscle as well. 

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.