The development of new drugs is frequently configured as a search for “blockers” of specific molecular signals (i.e., a search
for simple competitive antagonists). In contrast, allosteric antagonists can be sought for their ability to “permit” receptor
function, albeit described by altered kinetics, with regard to a particular agonist. Indeed, the use of permissive antagonists—or
better said, permissive “modulators,” for they may actually promote agonism—offers therapeutic modalities distinct from simple
“blockers.” An allosteric change that may obliterate receptor function with respect to one agonist, for example, may be inconsequential
with respect to another. An appreciation of this selective aspect of allostery can thus be relevant to any attempt to “block”
receptor function.