Novatretin Drug Interactions

Concomitant administration of vitamin A and other retinoids must be avoided because of the risk of hypervitaminosis A.
Investigations into the effect of acitretin on the protein binding of anticoagulants of the coumarin type (warfarin) revealed no interaction.
If acitretin is given concurrently with phenytoin, it must be remembered that acitretin partially reduces the latter's protein binding.
Low dose progesterone-only products (minipills) may be inadequate method of contraception during acitretin therapy.
Methotrexate, tetracyclines: see Contraindications.
Further interactions between acitretin and other substances (e.g. digoxin, cimetidine, combined estrogen/progestogen oral contraceptives) have not been observed so far.
In a study with healthy volunteers concurrent intake of a single dose of acitretin together with ethanol led to the formation of etretinate. This was already observed in vitro. In recent investigations, the formation of etretinate has also been observed in certain patients treated with acitretin. Until this phenomenon has been fully explained, the pharmacokinetic behaviour of etretinate must be taken into account. Therefore, since the elimination half-life of etretinate is approximately 120 days, contraceptive measures must be taken for 2 years after completion of acitretin treatment (see Pregnancy under Use in Pregnancy & Lactation).