Physostigmine treatment in various drug-induced intoxications

Eighty three patients who were comatose or confused due to intoxication with various drugs were treated repeatedly with 2 mg doses of physostigmine until maximal neurological improvement or side effects appeared. During therapy special attention was paid to the level of consciousness (Glasgow coma score) and to the general cardiorespiratory state. According to the main drug ingested the patients were divided into the following groups: anticholinergic (35 patients), benzodiazepine (12 patients), non-anticholinergic (22 patients) and unclassified (14 patients). The best antidotal effect of physostigmine was in the anticholinergic group (91%) and in the benzodiazepine group (67%), whereas in the non-anticholinergic and in the unclassified group only 32% and 50% of the patients, respectively, showed any improvement in mental condition during the physostigmine application. After the antidotal therapy, relapses occurred in 21/32 patients in the anticholinergic group, whereas the figures for the benzodiazepine and the non-anticholinergic groups were only 2/8 and 0/7. Major side effects of physostigmine were noted in two patients, one had ventricular extrasystoles and the other an acute grand mal attack. In this series the diagnostic value of physostigmine was considerable, but the therapeutic benefit was limited.