Pharmacological action – anti-inflammatory, anti-seborrheic, dermatoprotective, A-vitamin-like, anti-acne.
Normalizes terminal differentiation of cells, inhibits the proliferation of the epithelium of the ducts of the sebaceous glands, the formation of detritus, facilitates its evacuation. Reduces production and facilitates the release of sebum.
When administered, absorption is variable, bioavailability is low and variable; Taking together with food increases bioavailability by 2 times. Tmax – 2-4 hours Binding to blood plasma proteins (mainly with albumin) – 99.9%. Metabolized with the formation of three major biologically active metabolites – 4-oxo-isotretinoin (the main metabolite), tretinoin and 4-oxo-retinoin, as well as less significant metabolites, including glucuronides. Since in vivo isotretinoin and tretinoin are reversibly converted into each other, the metabolism of tretinoin is associated with the metabolism of isotretinoin. 20-30% of the dose of isotretinoin is metabolized by isomerization. In the pharmacokinetics of isotretinoin in humans, an important role may be played by enterohepatic circulation. In vitro studies have shown that isozretinoin metabolism involves isozymes CYP2C8, CYP2C9, CYP3A4 and CYP2B6 cytochrome P450. T1 / 2 isotretinoin – 19 hours, 4-oxo-isoretinoin – 29 hours. It is excreted by the kidneys and with bile in approximately equal amounts.
Indications for use
According to the instructions for Isotretinoin, the drug is intended for treatment of: Severe acne forms, including conglobata, nodular-cystic and forms with risk of scarring; Acne rash, not amenable to other types of treatment.
The use of Isotretinoin is contraindicated: In pregnancy, as well as at the stage of its planning; During breastfeeding; With severe hyperlipidemia; With hepatic insufficiency; With hypervitaminosis A; During the treatment with tetracyclines. Assign the drug, but with extreme caution to patients with kidney failure.