Benzydamine: Recreational Misuse of a Non Recreational Drug

Objective: Benzydamine hydrochloride is an indolic non steroidal anti-inflammatory drug available as mouthwash, vaginal douche, aerosol and pills. Being an over the counter drug it can be easily obtained and its recreational use has been described amongst street youth in developing countries. We describe an acute recreational benzydamine intoxication following voluntary ingestion of a commercially available vaginal douche and its clinical management. Case Report: a 35 years old woman affected by nutritional disorder and previous chronic ethanol abuse, detained in jail, was admitted to the Toxicology Unit of Careggi Florence Hospital, for hallucination and altered mental state following benzydamine ingestion. On arrival the patient reported the recreational use of 10 sachets commercially available vaginal douche (benzydamine 500 mg, per sachet) diluted in water. The patient was confused, agitated with mild tachycardia (96 bpm) and hypertension (135/95) with hallucinatory vision and muscle weakness. Toxicological screenings were negative for alcohol and common drugs of abuse. ECG showed QT interval prolongation. Treatment was symptomatic (diazepam i.v.) and supportive. The hallucinations lasted for almost six hours. ECG normalized after 24 hours. The patient remained in hospital for 6 days due to psychiatric comorbidility and was discharged in good health conditions. Conclusion: Benzydamine has structural similarity to dimethyltriptamine and for this reason could cause severe acute central nervous system toxicity. Although the exact mechanism of benzydamine hallucination is still unknown, multiple pharmacological interactions could be hypothesized.