Epidemic of poisoning caused by scopolamine disguised as Rohypnol tablets

An epidemic of scopolamine poisonings occurred in Oslo in 2008 among users of illicit drugs, caused by fake Rohypnol pills. The clinical features, diagnostic process, and handling of the epidemic are presented.

Suspected cases of scopolamine poisoning were extracted by reviewing registration forms from an ongoing prospective clinical study of acute poisonings in Oslo. Medical records of extracted contacts were examined and cases included according to specified clinical criteria.

Forty-four cases of probable scopolamine poisoning were registered. Main clinical features were mydriasis, visual hallucinations, plucking behavior, agitation, and coma. No clinical diagnosis of anticholinergic syndrome was made prior to forensic analysis of the tablets, the most frequent diagnosis up to this point being unspecified drug-induced psychosis. Later in the epidemic, scopolamine poisoning became the dominating diagnosis. Ten patients were admitted to psychiatric hospitals, the rest recovered in medical units, or left health care against medical advice.

Scopolamine poisonings are rare, but the resulting anticholinergic syndrome is well described. The syndrome was not recognized until the forensic analysis result strikingly changed how the patients were diagnosed and handled. A unique aspect of this epidemic was the intoxicating agent being scopolamine-containing tablets looking like Rohypnol, sold and used under the impression of being the latter.

Recognizing the anticholinergic syndrome is important to provide proper treatment. Forensic analysis was the key to correct diagnosis in this outbreak, demonstrating its importance in verifying an epidemic of poisoning by fake drugs.