Drug abuse is an important sociomedical problem in large metropolitan areas. Drug addicts represent a group with particularities, since they hesitate to seek medical care and often refuse hospitalization. Therefore, there is a scarcity of data on drug abuse-related calls. The burden imposed by such calls on emergency health services has not been evaluated in detail. The objectives of this study are to: (1) assess the profile of drug abuse-related calls in a large European metropolis, including the spatiotemporal distribution, as well as the frequency and variability of cancellations; and (2) evaluate the mobilization of emergency prehospital care services in response to the calls. In 2005, the Hellenic National Centre for Emergency Care received 5,836 emergency drug abuse-related calls pertaining to the metropolitan area of Athens, Greece. The analysis focused on: (1) spatiotemporal features of calls/cases; (2) step-by-step cancellation rates in the mobilization of ambulances or other means (mobile intensive care units, specially equipped motorcycles, and super-mini city cars); and (3) response time of the mobilized means. Pearson's chi-square, goodness-of-fit chi-square, and the Kruskal-Wallis tests were used as appropriate. Drug abuse-related calls represented 2% of all emergency calls. Only one-third of these cases were transported to the Accident and Emergency Departments of area hospitals. A total of 9% of the calls were cancelled before transportation arrived; another 20% of victims could not be found when authorities arrived on-scene, and 36% of patients refused transport to the hospital. The cancellation rate is significantly higher in the evening and at night, as well as in summer and autumn. The major burden is imposed on the municipality of Athens (67% of all calls). Drug abuse-related calls represent a significant load for emergency medical services in metropolitan Athens. However, a relatively small percentage of the drug addicts finally are transported to the hospital. Appropriately equipped motorcycles seem to be an effective means for the prehospital management of drug-abuse cases.