Epidemiological assessment of 160 cases of insulin overdose recorded in a regional poisons unit.
OBJECTIVE
Overdoses with insulin are common, and cases of hypoglycemic coma can be fatal and cause cerebral defects. However, data published on this topic are rare, consisting mostly of case reports or reports in a small number of patients. The present investigation analyzes inquiries made to a regional poisons unit involving overdoses with insulin.


METHODS
A total of 175,890 inquiries for the years 1995-2003 (until September) were evaluated. 160 inquiries were received by telephone concerning insulin overdoses, and a standardized questionnaire was sent to the physicians asking for follow-up information. The cases were analyzed in regard to etiology, type of insulin used, concomitant substances being taken by the patient, symptoms and clinical outcome.


RESULTS
Of the 160 inquiries investigated, 53.1% of the patients were female, 43.1% male and in 3.8% the sex of the patient was unknown. The average age was 44.7 years. 89.4% involved suicidal or parasuicidal cases, 5.0% were accidental overdoses and 1.9% involved cases of criminal overdose (3.7% were for other reasons). Rapidly acting insulins (57.8%) were used more commonly than long-acting formulations (42.8%). Benzodiazepines were the most frequently ingested concomitant medication (37.5%) with ethanol 15.6%, antihypertensive drugs 12.5% and antidepressants 10.0%. Most patients presented with a delay of 2-3 hours after insulin administration (15.0%). Almost 50% of the patients presented within the first 6 hours. According to the Poisoning Severity Score, no symptoms were observed in 16.8% of the patients, minor symptoms in 36.8%, major symptoms in 25.2% and serious symptoms in 21.3%. Information concerning the clinical outcome (75 cases) showed that a full recovery occurred in most patients (94.7%), but in 2.7% there were cerebral defects and 2.7% of the patients died.


CONCLUSIONS
The etiology of overdoses with insulin was mainly deliberate self-poisoning. Physicians should take into account that long-acting insulin formulations and concomitant substances were frequently used. For overdoses with insulin, relatively high rates of serious symptoms and deaths were observed.
von Mach
M A
MA
II Medical Department, Division of Clinical Toxicology, University Hospitals, Mainz, Germany. marcm@giftinfo.uni-mainz.de
Meyer
S
S
Omogbehin
B
B
Kann
P H
PH
Weilemann
L S
LS
D000328:Adult; D062787:Drug Overdose; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D007004:Hypoglycemic Agents / Q000506:poisoning*; D007328:Insulin / Q000506:poisoning*; D008297:Male; D011039:Poison Control Centers; D016728:Self-Injurious Behavior / Q000453:epidemiology*; D013405:Suicide / Q000706:statistics & numerical data
D007004:Hypoglycemic Agents; D007328:Insulin