Electronic dance music festivals (EDMF) are a unique subset of music mass gatherings. Besides the already more significant burden on in-event health services (IEHS) that comes with these festivals, EDMF are also known for their illicit drug use, with their attendees at high risk for illegal drug use.

Encounter data from all patients seen and treated by IEHS at an annual outdoor multi-day EDMF (focused on hardstyle dance music) in August 2019 were analyzed. Based on the chief complaint, and medical and nursing notes, a list was consolidated into 31 reasons for the consultation of IEHS. The most common reasons for consulting IEHS were analyzed.

This outdoor hardstyle dance event had 30,000 attendees, of which 580 visited IEHS. This resulted in a patient presentation rate of 19.3/1,000 attendees. Four were transported to the hospital (transport to hospital rate: 0.13/1,000 attendees). The most prevalent reason to consult IEHS were lacerations and abrasions (9.66%), sprains (9.48%), and headaches (7.59%). Only 4.83% of all patients (n = 12) presented with adverse effects of illicit drug use. Of interest is that twelve patients with intoxications (42.86% of all intoxicated patients) were initially triaged as life-threatening, mainly due to obstructed airways. Only one of these twelve needed endotracheal intubation and was transported to the hospital. All other intoxicated patients returned to the event. No direct relationship between gender and the chief complaint was found.

Besides typical patient presentations, illicit drug use with its adverse effects can seriously impact IEHS. These results confirm the need for highly trained (Advanced life support level) IEHS at EDMF. Competent IEHS can mitigate the burden of these events on regular EMS.