Timing and frequency of physostigmine redosing for antimuscarinic toxicity.
We sought to determine how frequently antimuscarinic-poisoned patients receiving physostigmine receive multiple doses of physostigmine, the length of time between physostigmine doses, and what impact multiple doses of physostigmine have on the disposition and total length of hospital stay. We performed a retrospective chart review of patients given physostigmine for likely antimuscarinic toxicity. A total of 45 patients met inclusion criteria. We abstracted patient demographics, vital signs, physical exam findings, electrocardiograms, the timing and dose of physostigmine, the implicated antimuscarinic agents, and disposition from the hospital. We counted the number of patients who required multiple physostigmine doses and calculated the time to repeat dosing. Fourteen of the 45 patients (31%) given physostigmine for antimuscarinic toxicity received multiple doses: nine patients (20%) received two doses, three patients (6.6%) received three doses, and two patients (4.4%) received four doses. Less than 5.5 h elapsed between sequential physostigmine doses, and less than 6.5 h elapsed between the first and last dose. Forty-five percent of patients receiving one dose of physostigmine were discharged from the emergency department (ED) and 36% of patients receiving more than one dose of physostigmine were discharged from the ED. Whether admitted or discharged, there was no statistically significant difference in the length of hospital stay between patients receiving one or multiple doses of physostigmine. Repeated physostigmine administration is not frequently needed in medication-induced antimuscarinic toxicity. Patients are not likely to require further physostigmine redosing more than 6.5 h from their first dose.
Rosenbaum
Christopher
C
Department of Emergency Medicine, Division of Medical Toxicology, University of Massachusetts Medical School, Worcester, MA, USA.
Bird
Steven B
SB
D000328:Adult; D017109:Akathisia, Drug-Induced / Q000188:drug therapy; D001341:Autonomic Nervous System / Q000187:drug effects* / Q000503:physiopathology; D002800:Cholinesterase Inhibitors / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D018727:Muscarinic Antagonists / Q000633:toxicity*; D020258:Neurotoxicity Syndromes / Q000188:drug therapy* / Q000503:physiopathology; D010830:Physostigmine / Q000008:administration & dosage*; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
D002800:Cholinesterase Inhibitors; D018727:Muscarinic Antagonists; D010830:Physostigmine
JAMA. 1974 Dec 4;230(10):1405-7
4479642
N Engl J Med. 1985 Aug 22;313(8):474-9
4022081
JAMA. 1975 Mar 3;231(9):941-3
1173100
Ann Emerg Med. 1980 Nov;9(11):588-90
7001962
Br Med J (Clin Res Ed). 1984 Feb 25;288(6417):601-3
6421394
Clin Pediatr (Phila). 1976 Dec;15(12):1123-8
825344
Pediatrics. 1973 Sep;52(3):449-51
4147165
Am J Emerg Med. 1998 Sep;16(5):505-7
9725967
JACEP. 1976 Jun;5(6):436-9
933411
Ann Emerg Med. 2003 Jul;42(1):14-9
12827117
Curr Med Chem. 2004 Feb;11(3):279-96
14965232
J Emerg Med. 1991 Jul-Aug;9(4):275-7
1861064
JAMA. 1977 Jun 13;237(24):2632-3
576990
J Toxicol Clin Toxicol. 1998;36(1-2):43-5
9541041
Anaesthesia. 2005 May;60(5):433-8
15819761
Am Fam Physician. 1992 Aug;46(2):526-30
1636566
Ther Apher Dial. 2009 Apr;13(2):147-9
19379154
Vet Hum Toxicol. 1993 Feb;35(1):32-3
8434447
Ann Emerg Med. 2000 Apr;35(4):374-81
10736125
Life Sci. 2000 Nov 24;68(1):29-39
11132243
JAMA. 1974 Dec 4;230(10):1433-4
4547804
Toxicol Rev. 2006;25(2):99-138
16958557
J Clin Psychiatry. 1983 Dec;44(12):463-4
6654839
J Emerg Med. 2003 Aug;25(2):185-91
12902007
Ann Emerg Med. 1996 Mar;27(3):305-8
8599488
JAMA. 1976 Apr 5;235(14):1474-6
946448
Pediatr Emerg Care. 1998 Jun;14(3):224-6
9655671
Clin Toxicol (Phila). 2006;44(3):319-25
16749552