Description of the medicine: Etretinate (Etretinate)
Ethyl 9- (4-methoxy-2, 3, 6-trimethylphenyl) -3, 7-dimethyl2, 4, 6, 8-nonatetraenoic acid.
Synonyms: Tigazon, Tigason, Tegison, Tigasan, Tigason.
The chemical structure is similar to retinol, it is a synthetic aromatic derivative of retinoic acid (retinoid).
The synthesis of etretinate and other derivatives of retinoic acid (isotretione, etc.) was undertaken in connection with the therapeutic efficacy of retinol (vitamin A) in a number of skin diseases (see Retinol).
It turned out that etretinate (tigazone) has a therapeutic effect in psoriasis, ichthyosis, Darier’s disease, discoid lupus erythematosus and some other dermatological diseases.
The drug in the form of capsules is prescribed orally. The dose for adults with psoriasis is usually 30 mg per day (3 capsules of 10 mg); taken with food or washed down with milk. After 2 to 4 weeks of treatment, in case of good tolerance, you can increase the dose to 75 mg per day (3 capsules of 25 mg). The maintenance dose is then 30 mg per day. Usually, the course of treatment lasts 6 to 8 weeks. In relapses, repeated courses of treatment are performed.
For the treatment of other diseases, 10 to 30 mg per day is prescribed.
The drug has a therapeutic effect, but relatively often causes side effects.
Possible side effects (skin itching, dry mucous membranes of the oral cavity, desquamous cheilitis, hair loss, high blood lipids, tissue calcification, ossification, etc.) require careful monitoring of the condition of patients, individual dosage.
A serious side effect of tigazone is its teratogenic effect. Therefore, it can not be prescribed to women not only during pregnancy, but also throughout the childbearing age.
Tigazone is not used for liver and kidney failure (80% of etretinate is excreted in the form of metabolites with bile, 20% in urine). The drug is excreted from the body slowly; cumulation phenomena are possible.
Due to the increased risk of hepatitis, etretinate should not be used simultaneously with methotrexate.
Given the possibility of severe side effects, you should be very careful about prescribing tigazone to children (only with special indications). Dose 0.5 mg per 1 kg of body weight per day. The maintenance dose is 0.1 mg / kg per day or every other day.
Release form: capsules containing 0.01 or 0.025 g (10 or 25 mg) of etretinate.
Tigazone (etretinate) continues to be prescribed in cases of inefficiency of other drugs, however, due to side effects, its use remains limited. A search is underway for other similar drugs. One of the new drugs of this series is acitretin (Acitretin, Etretin).
Acitretin is close in structure to etretinate. It is an acid corresponding to etretinate, i.e., it contains a C00H group in the end link of the side chain instead of the С00С Н group. According to the action, acitretin is also close to etretinate (tigazone), but differs in pharmacokinetic parameters, is more rapidly excreted from the body.