the desired effect in 95% of the population. In anaesthesia, the term ED95 is also used when referring to the pharmacology of neuromuscular blocking drugs. In this context, it is the dose which will cause 95% depression of the height of a single muscle twitch, in half of the population. Put another way, it is the ED50 for 95% reduction in twitch height. The single twitch response occurs when a nerve stimulator is used to stimulate the ulnar nerve, and the degree of twitch of the adductor pollicus muscle is measured. A more accurate nomenclature when used in this way would be "ED5095". See also List of abbreviations used in medical prescriptions Certain safety factor References Clinical pharmacology Mathematics in medicine