Etretin

Etretin is a synthetic retinoid primarily used in the field of dermatology for the treatment of severe psoriasis and other skin disorders. It is a derivative of vitamin A and functions by modulating the growth and differentiation of epithelial cells.

Medical Uses

Etretin is indicated for the treatment of severe psoriasis, particularly in cases where other treatments have failed. It is also used in the management of other keratinization disorders such as ichthyosis and pityriasis rubra pilaris. The drug is known for its ability to normalize the growth cycle of skin cells, thereby reducing the formation of scales and plaques.

Mechanism of Action

Etretin works by binding to retinoic acid receptors (RARs) in the skin. This binding alters the expression of genes involved in cell differentiation and proliferation. By influencing these genetic pathways, etretin helps to restore normal skin cell turnover and reduce the symptoms of hyperkeratotic conditions.

Side Effects

Common side effects of etretin include dry skin, cheilitis (inflammation of the lips), and xerophthalmia (dry eyes). More severe side effects can include hepatotoxicity, hyperlipidemia, and teratogenicity. Due to its potential for causing birth defects, etretin is contraindicated in pregnancy and requires strict contraceptive measures for women of childbearing age.

Contraindications

Etretin is contraindicated in patients with known hypersensitivity to retinoids, in pregnant women, and in those with severe liver or kidney dysfunction. It should be used with caution in patients with a history of hyperlipidemia or alcoholism.

Pharmacokinetics

Etretin is well-absorbed when taken orally, with peak plasma concentrations occurring within 2-4 hours. It is highly protein-bound and metabolized in the liver. The drug has a long elimination half-life, which can lead to accumulation in the body with prolonged use.

Related Compounds

Etretin is related to other retinoids such as acitretin, isotretinoin, and tretinoin. These compounds share similar mechanisms of action but differ in their specific indications and side effect profiles.

See Also

• Psoriasis
• Retinoid
• Vitamin A
• Acitretin
• Isotretinoin
• Tretinoin