Psoriasis treatment: Unconventional and non-standard modalities in the era of biologics

Table 6 Drugs interacting with retinoids

Interacting drug	Mechanism/comments
Drugs that may increase retinoids levels and/or toxicity
Vitamin A	Induces hypervitaminosis A like toxicities
Tetracycline, doxycycline and minocycline	Increase pseudotumour cerebri risk
Macrolides, Azoles, etc.	Other CYP 3A4 inhibitors increase its level
Drugs that may reduce retinoids level
Rifampicin, rifabutin	Induction of CYP 3A4
Anticonvulsants-phenytoin, Phenobarbital, carbamazepine	Induction of CYP 3A4
Drugs that may synergistically increase hepatotoxicity
Methotrexate	Common target organ for toxicity-liver
Alcohol	Common target organ for toxicity-liver
Drugs whose levels are changed by retinoids
Cyclosporine A	Cyclosporine A levels are increased via competition for CYP 3A4