CYP3A4 and psoriasis: Pharmacokinetic: Tribulus terrestris inhibits CYP3A4, increasing the concentration and side effects of trazodone (metabolized by CYP3A4). By this interaction, Tribulus terrestris may increase the risk of psoriasis relapse. This is of clinical significance if trazodone is used in daily doses above 300 mg when it reveals significant SSRI activity