Bupropion × Dexamethasone

Dexamethasone is a potent CYP3A4 inducer and weak CYP2B6 inducer (which metabolises bupropion). Bupropion levels may fall, giving partial loss of antidepressant effect. The glucocorticoid itself also lowers the seizure threshold.

Seizures (generalised tonic-clonic or focal), agitation, tremor, insomnia. Patients with prior epilepsy or eating disorders are at particular risk.

For prolonged dexamethasone therapy, bupropion may be increased by 50% with clinical monitoring. For short courses, no adjustment is usually needed. After dexamethasone stops, induction persists for 1–2 weeks.