Serotonin & Antiserotonin Drugs — Practice

A 19-year-old woman with a first episode of major depression started on an SSRI also self-medicates with a high dose of tramadol for dysmenorrhoea. She develops agitation, hyperthermia, diaphoresis, inducible clonus and hyperreflexia. Besides stopping the offending drugs, which agent is the specific serotonin antagonist used in management?