title: ["Usual" cannabis abuse producing an unusual incident].
abstract: METHODS
  A 17-year-old male presented in an agitated, deranged state with rapidly increasing swelling of the neck. Except for regular abuse of cannabis there was no medical history of note. He had a sinus tachycardia (130 bpm), a slow pupillary reflex, bilateral hyposphagma and subcutaneous emphysema around the neck and shoulders.
  
  
  METHODS
  Laboratory tests showed elevated inflammatory markers. The chest X-ray demonstrated a bilateral pneumothorax and large subcutaneous emphysema. Subsequent computed tomography of neck and thorax showed an extensive pneumomediastinum and the described subcutaneous emphysema. There was no evidence of a ruptured trachea or esophageal perforation. The underlying cause was presumed to have been a Valsalva maneuver during marijuana smoking.
  
  
  METHODS
  As the pneumothorax was completely reabsorbed, no chest drains were inserted and the patient was transferred to our toxicological intensive care unit. Recurring drug-induced psychosis had to be treated with repeated doses of haloperidol. The emphysema was slowly reabsorbed without any further complication. The patient was transferred back to a psychiatric ward after five days.
  
  
  CONCLUSIONS
  Although cannabis is thought to be one of the "safe" drugs, its abuse can have life-threatening effects. One complication is the occurrence of a pneumothorax after a Valsalva maneuver. As the rate of cannabis abuse has been increasing during the last few years, the risk of life-threatening complications should be mentioned in relevant publications and as part of drug education. Patients presenting with dyspnea should always be carefully questioned about possible drug abuse.
authors.affiliation: Klinikum Nürnberg Nord, Medizinische Klinik 2, Intensivmedizin-Toxikologie, Lehrstuhl Innere Medizin V-Geriatrie, FAU Erlangen-Nürnberg. heppner@klinikum-nuernberg.de
authors.forename: H J
authors.initials: HJ
authors.lastname: Heppner
authors.forename: C
authors.initials: C
authors.lastname: Sieber
authors.forename: K
authors.initials: K
authors.lastname: Schmitt
mesh_terms: D000293:Adolescent; D014150:Antipsychotic Agents / Q000627:therapeutic use; D004417:Dyspnea / Q000139:chemically induced; D005130:Eye Hemorrhage / Q000139:chemically induced; D006220:Haloperidol / Q000627:therapeutic use; D006801:Humans; D008297:Male; D002189:Marijuana Abuse / Q000150:complications*; D008385:Marijuana Smoking / Q000009:adverse effects; D008478:Mediastinal Emphysema / Q000139:chemically induced* / Q000175:diagnosis; D011030:Pneumothorax / Q000139:chemically induced* / Q000175:diagnosis; D011605:Psychoses, Substance-Induced / Q000188:drug therapy / Q000209:etiology; D012008:Recurrence; D013352:Subcutaneous Emphysema / Q000139:chemically induced* / Q000175:diagnosis; D014057:Tomography, X-Ray Computed; D014636:Valsalva Maneuver
chemical_list: D014150:Antipsychotic Agents; D006220:Haloperidol