Tags

Type your tag names separated by a space and hit enter

Physostigmine does not effect arousal but produces toxicity in an animal model of severe gamma-hydroxybutyrate intoxication.
Acad Emerg Med. 2005 Mar; 12(3):185-9.AE

Abstract

OBJECTIVES

Physostigmine is an acetylcholinesterase inhibitor and can produce fasciculations, seizures, bradycardia, and asystole. gamma-hydroxybutyrate (GHB) increases acetylcholine levels in the central nervous system and can decrease heart rate. Despite this, physostigmine has been proposed as an arousal agent to treat coma from overdoses of GHB. The authors hypothesized that in the setting of severe GHB intoxication, physostigmine would reverse sedation without producing adverse effects such as a decrease in heart rate, seizures, and fasciculations.

METHODS

GHB intoxication was induced in 20 rats by intraperitoneal injection of 700 mg/kg of the GHB precursor gamma-butyrolactone. One hour later, rats were randomly assigned to receive either physostigmine (0.06 mg/kg) intraperitoneally or an equivalent volume of saline. After administration of physostigmine, rats were continuously monitored by a blinded observer for arousal (return of righting reflex), fasciculations, and seizures. Heart rate and respiratory rate were recorded at 0, 5, 15, and 60 minutes after administration of physostigmine. Data were analyzed using repeated-measures analysis of variance and chi-square test. A pretest sample size calculation determined that 10 rats per group would detect a change in arousal from 0% to 50% and a 10% change in heart rate.

RESULTS

No rats in either group had arousal within one hour (p = 1.0); however, ten of ten physostigmine-treated rats developed signs of physostigmine toxicity (fasciculations, 7; seizures, 3), while no controls developed signs of physostigmine toxicity (p = 0.00). The authors were unable to detect a decrease in heart rate.

CONCLUSIONS

Physostigmine did not produce a 50% change in arousal as measured by a return of righting reflex but did produce physostigmine toxicity (fasciculations and seizures) in this rat model of severe GHB intoxication.

Authors+Show Affiliations

St. Luke's-Roosevelt Hospital Center, 1000 10th Avenue, Room GE01, New York, NY 10019, USA. toxtod@aol.comNo affiliation info available

Pub Type(s)

Journal Article

Language

eng

PubMed ID

15741579

Citation

Bania, Theodore C., and Jason Chu. "Physostigmine Does Not Effect Arousal but Produces Toxicity in an Animal Model of Severe Gamma-hydroxybutyrate Intoxication." Academic Emergency Medicine : Official Journal of the Society for Academic Emergency Medicine, vol. 12, no. 3, 2005, pp. 185-9.
Bania TC, Chu J. Physostigmine does not effect arousal but produces toxicity in an animal model of severe gamma-hydroxybutyrate intoxication. Acad Emerg Med. 2005;12(3):185-9.
Bania, T. C., & Chu, J. (2005). Physostigmine does not effect arousal but produces toxicity in an animal model of severe gamma-hydroxybutyrate intoxication. Academic Emergency Medicine : Official Journal of the Society for Academic Emergency Medicine, 12(3), 185-9.
Bania TC, Chu J. Physostigmine Does Not Effect Arousal but Produces Toxicity in an Animal Model of Severe Gamma-hydroxybutyrate Intoxication. Acad Emerg Med. 2005;12(3):185-9. PubMed PMID: 15741579.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Physostigmine does not effect arousal but produces toxicity in an animal model of severe gamma-hydroxybutyrate intoxication. AU - Bania,Theodore C, AU - Chu,Jason, PY - 2005/3/3/pubmed PY - 2006/3/11/medline PY - 2005/3/3/entrez SP - 185 EP - 9 JF - Academic emergency medicine : official journal of the Society for Academic Emergency Medicine JO - Acad Emerg Med VL - 12 IS - 3 N2 - OBJECTIVES: Physostigmine is an acetylcholinesterase inhibitor and can produce fasciculations, seizures, bradycardia, and asystole. gamma-hydroxybutyrate (GHB) increases acetylcholine levels in the central nervous system and can decrease heart rate. Despite this, physostigmine has been proposed as an arousal agent to treat coma from overdoses of GHB. The authors hypothesized that in the setting of severe GHB intoxication, physostigmine would reverse sedation without producing adverse effects such as a decrease in heart rate, seizures, and fasciculations. METHODS: GHB intoxication was induced in 20 rats by intraperitoneal injection of 700 mg/kg of the GHB precursor gamma-butyrolactone. One hour later, rats were randomly assigned to receive either physostigmine (0.06 mg/kg) intraperitoneally or an equivalent volume of saline. After administration of physostigmine, rats were continuously monitored by a blinded observer for arousal (return of righting reflex), fasciculations, and seizures. Heart rate and respiratory rate were recorded at 0, 5, 15, and 60 minutes after administration of physostigmine. Data were analyzed using repeated-measures analysis of variance and chi-square test. A pretest sample size calculation determined that 10 rats per group would detect a change in arousal from 0% to 50% and a 10% change in heart rate. RESULTS: No rats in either group had arousal within one hour (p = 1.0); however, ten of ten physostigmine-treated rats developed signs of physostigmine toxicity (fasciculations, 7; seizures, 3), while no controls developed signs of physostigmine toxicity (p = 0.00). The authors were unable to detect a decrease in heart rate. CONCLUSIONS: Physostigmine did not produce a 50% change in arousal as measured by a return of righting reflex but did produce physostigmine toxicity (fasciculations and seizures) in this rat model of severe GHB intoxication. SN - 1553-2712 UR - https://wwww.unboundmedicine.com/medline/citation/15741579/Physostigmine_does_not_effect_arousal_but_produces_toxicity_in_an_animal_model_of_severe_gamma_hydroxybutyrate_intoxication_ DB - PRIME DP - Unbound Medicine ER -