Background Iatrogenic disease is an important cause of admission to hospitals in the Internal Medicine Unit. It is very important to evaluate the doses of the drugs indicated, renal and hepatic functions and possible interactions in order to avoid it.

Purpose To evaluate the prevalence of admissions for iatrogenic illness in the Internal Medicine Unit and to determine which drugs were most frequently associated with adverse events.

Material and methods Retrospective observational analysis in which we investigated patients diagnosed with iatrogenic conditions admitted to the Department of Internal Medicine during 2013. Data were collected related to the drug responsible for the adverse reaction, the severity and type, and also demographic data such as age and gender.

Results 273 patients were admitted to the Internal Medicine Unit. 29 (10.62%) of these admissions were caused by a drug. The mean age was 80.1 ± 6.3 years (55% were male). Drugs implicated and adverse reactions were: 1. Digitalis drugs (27.6%): bradycardia and heart failure. 2. Oral anticoagulants (24.1%): 4 gastrointestinal bleeds and 3 soft tissue hematomas. 3. Diuretics (13.8%): 3 hyponatremia and 1 renal failure. 4. Corticosteroids (10.3%): severe hyperglycaemia. 5. Neuroleptics (10.3%): 2 confusional syndrome and 1 hepatitis. 6. Nonsteroidal anti-inflammatories in 1 person (3.5%): renal failure. 7. Insulin (3.5%): hypoglycaemia. 8. Angiotensin converting enzyme inhibitors (3.5%): renal failure. 9. Spironolactone in 1 person (3.5%): hyperkalaemia. Two patients died (6.8% of iatrogenic patients) one by digitalis poisoning and another because of gastrointestinal bleeding.

Conclusion Drug-induced illness is an important cause of admission to our hospital. Drugs with a narrow therapeutic index such as oral anticoagulants or digoxin are the main ones responsible.

References and/or acknowledgements Hospital Universitario Puerta del Mar

No conflict of interest.