Use of retinoids in dermatology

Background: Retinoid, whose existence was first known in the 20th century, was initially referred to as a naturally occurring substance with vitamin A action. However, now it has become a generic term for all substances exhibiting an active action through the retinoid receptor located in the nucleus of the cells. Retinoids are biologically important substances involved in many functions, including reproduction, embryonic morphogenesis, regulation of epithelial proliferation and differentiation, reduction of sebaceous gland, immune and anti-inflammatory effects, tumor prevention, and effects on extracellular matrix components. Current Concepts: Topical retinoids are used to treat several conditions, including acne, photoaging, and psoriasis. Their side effects are dose-related skin irritations, while teratogenicity risk is rare to non-existent. Systemic retinoids are a treatment of choice for acne and keratinization disorders. They are also useful for the treatment of psoriasis, pityriasis rubra pilaris, cutaneous T-cell lymphoma, and chronic hand eczema. Systemic retinoid therapy requires the careful patient selection and monitoring due to associated teratogenicity. Other important side effects are hypertriglyceridemia, dryness of lips, blepharoconjunctivitis, bone pain, increased muscle tone, myopathy, hypothyroidism, and neutropenia. Discussion and Conclusion: Awareness of the side effects and proper use of retinoids are important for successful treatment outcomes of the above-mentioned dermatological conditions.