Time Course of Serum Dextromethorphan Concentrations in a Case of Serotonin Syndrome After Massive Overdose

05 December 2025 : Case report Japan

Management of emergency care, Rare coexistence of disease or pathology

Seigo Yamada^{ABDEF 1}, Hiroaki Taniguchi

^{ABCDEF 2}, Takero Terayama

^{ABDEF 3*}, Akashi Hayakawa^{D 4}, Hiroyuki Toda^{D 4}, Hiroko Abe^{C 5}, Tetsuro Kiyozumi^{ABDF 1}

DOI: 10.12659/AJCR.949204

Am J Case Rep 2025; 26:e949204

Authors information Article notes Copyright and License information

Introduction Case Report Discussion Conclusions References

Related articles Order reprints Share article Share by email

View HTML version

Table 1 Summary of blood dextromethorphan levels and clinical course of serotonin syndrome.

Time from ingestion	Blood DXM level	Clinical course
13 h after dose ingestion	398 ng/mL	Impaired consciousness, autonomic instability, clonus, seizure, and agitation
Day 2	Not done	Agitation
Day 3	26 ng/mL	Agitation
Day 4	2 ng/mL	Hallucinations and delusions
Day 5	Undetectable	Hallucinations and delusions
DXM – dextromethorphan.

Back to the Article