dose not antagonize and may prolong the phase 1 block of depolarizing muscle relaxants (eg. succinylcholine); use with caution in patients with epilepsy, asthma, hyperthyroidism, cardiac arrhymias, or peptic ulcer; adequate facilies should be available for cardiopulmonary resuscitation when testing and adjusting dose for myasthenia gravis; have atropine and epiephrine ready to treat hypersensitivity reactions; overdosage may result in cholinergic crisis, this must be distinguished from myasthenic cirsis; anticholinesterasa insensitivity can develop for prolonged periods