The plasma concentration of threohydrobupropion and erythrohydrobupropion is equal or higher than bupropion. Due to the lack of data on their inhibition potential towards CYP enzymes, bupropion is classified as possibly porphyrinogenic. Risk for gastrointestinal adverse events in the form of nausea, vomiting, abdominal pain and obstipation motivates vigilance against insufficient intake of food, especially of carbohydrate.

Bupropion is also known as amfebutamone.

Bupropion is indicated for the treatment of depression. Very common and common side effects that can be potentially porphyrinogenic through reduction in carbohydrate intake and that also can be confused with an acute porphyria attack are nausea, vomiting, abdominal pain and obstipation. Other common side effects are anorexia, anxiety, hypertension, fever, chest pain and asthenia.

Bupropion is metabolised by CYP2B6 to the major active metabolite hydroxybupropion. Other active metabolites are threohydrobupropion and erythrohydrobupropion (SPC). The mean half-life elimination fo r bupropion and its major active metabolite are 20 hours. It is an inhibitor of CYP2D6 in vivo (Isoherranen 2009 and SPC). When co-administered, carbamazepine decreased the AUC of bupropion by 90%. It is possible that carbamazepine induced the metabolism of bupropion via CYP3A4 (Ketter 1995). The plasma concentration of threohydrobupropion and erythrohydrobupropion is equal or higher than bupropion, but their inhibition potential towards CYP450 enzymes has not been studied (SPC).

A study in primary cultures of chick embryo liver cells suggests that patients with acute porphyria may be at greater risk for developing porphyric attacks when treated with bupropion (Lambrecht 1999).