Neuromuscular blockers, specific

Several different neuromuscular blockers are currently available, and the choice of a specific agent depends primarily on the desired length of action and the agent s potential side effects (Table 11-3).21,23 Possible side effects include cardiovascular problems (tachycardia), increased histamine release, increased... 

Life-threatening anaphylactic reactions that rarely occur during general anesthesia are mostly due to neuromuscular blockers. They may be due to cross-allergy mediated by drug-specific IgE antibodies to the quaternary ammonium moiety of the neuromuscular blocker molecule, perhaps with a contribution from IgE-independent mechanisms. Quaternary ammonium compounds, such as benzalkonium, in cosmetics and toiletries may play a role in sensitization (7). 

Baldo BA, McDonnell NJ, Pheun NH. Drug-specific cyclodextrans with emphasis on sugammadex, the neuromuscular blocker rocuronium and perioperative anaphylaxis impUcations for drug aUeigy. Clin Exp AUeigy. 2011 41 1663-78. 

There is at least one group of drugs, the neuromuscular blockers (and probably more to be identified), that can specifically elicit antibody-induced mast cell activation and release without first undergoing coupling to a macromolecular carrier. For these drags, the di- or multi-valency which is an inherent part of the molecular structure, initiates mediator release by CToss-Unking cell-bound antibodies. 

Fig. 7.15 Chemical structure of one of the eight a-1-4-linked glucopyranose units of sugammadex, 6-perdeoxy-6-per(2-carboxyethyl)thio-Y-cyclodextrin sodium salt, showing the thio(2-carboxyethyl)sodium group linked at position 6 of the glucose molecule. From Baldo BA et al. Drug-specific cyclodextrins with emphasis on sugammadex, the neuromuscular blocker rocuronium and perioperative anaphylaxis implications for drug aUeigy. Qin Exp Allergy 2011 41 1663. Reprinted with permission from lohn Wiley and Sons...

Furthermore, these allosteric effects were shown to be truly subtype specific, depending on the nature of the allosteric modulating compound. Thus, alcuronium exerts positive copperativity with [3H]NMS at the M2 and M4 but not at the Mi and M3 receptors [26,27], while other neuromuscular junction blockers such as stercuronium, pancuronium, and d-tubocurarine have been shown to exhibit their effects via an allosteric mechanism specifically on the M2 receptors [28-30]. 

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