Evaluation of centrally acting cholinesterase inhibitor exposures in adults.
BACKGROUND
There are 4 centrally acting cholinesterase inhibitors (CA-ChEI) available in the US: tacrine, galantamine, rivastigmine, and donepezil. Documented clinical experience involving exposure to these agents is limited. The lack of information makes decisions involving excessive or unintended CA-ChEI exposure difficult.


OBJECTIVE
To assess the effects, demographics, and outcomes of CA-ChEI exposures reported to US poison centers.


METHODS
A retrospective review of the Toxic Exposure Surveillance System of the American Association of Poison Control Centers data of acute and acute-onchronic exposures involving only a CA-ChEI in patients 19 years of age or older with documented medical outcomes from 2000-2005 was performed.


RESULTS
There were 1026 records that met criteria for this study. Patients aged 70-89 years made up 73% of reports; 69% of the patients were female. Moderate (197) and major outcomes (20) accounted for 21% of exposures. There were no deaths. Clinical effects that occurred in 5% or more of patients included vomiting (34%), nausea (28%), diarrhea (12%), dizziness/vertigo (9.9%), drowsiness/lethargy (7.7%), diaphoresis (7.4%), tremor (5.2%), and bradycardia (5%). Patients were admitted to the hospital in 19% of all exposures. Of those patients, 42% were admitted to a critical care unit. The majority (65%) of exposures were attributed to unintentional therapeutic error. Patients received at least one form of therapy in 47% of exposures, including intravenous fluid (111), antiemetic (48), atropine (17), benzodiazepine (15), oxygen (14), antihypertensive (4), pralidoxime (4), intubation (3), antihistamine (2), antiarrhythmic (1), anticonvulsant (1), and pacemaker (1).


CONCLUSIONS
The majority of patients evaluated in this retrospective study experienced no or mild effect; however, significant or life-threatening effects were observed in a small group of patients and an appreciable number of patients were admitted to a healthcare facility.
McCain
Keith R
KR
Arkansas Poison Control Center, Little Rock, AR 72205, USA. krmccain@uams.edu
Sawyer
Tama S
TS
Spiller
Henry A
HA
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002800:Cholinesterase Inhibitors / Q000008:administration & dosage* / Q000009:adverse effects*; D000077265:Donepezil; D005260:Female; D005702:Galantamine / Q000008:administration & dosage / Q000009:adverse effects; D005767:Gastrointestinal Diseases / Q000139:chemically induced / Q000453:epidemiology; D006801:Humans; D007189:Indans / Q000008:administration & dosage / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D048448:Phenylcarbamates / Q000008:administration & dosage / Q000009:adverse effects; D010880:Piperidines / Q000008:administration & dosage / Q000009:adverse effects; D011039:Poison Control Centers / Q000639:trends; D012189:Retrospective Studies; D000068836:Rivastigmine; D013619:Tacrine / Q000008:administration & dosage / Q000009:adverse effects
D002800:Cholinesterase Inhibitors; D007189:Indans; D048448:Phenylcarbamates; D010880:Piperidines; D005702:Galantamine; D013619:Tacrine; D000077265:Donepezil; D000068836:Rivastigmine