Topical Vitamin A for the skin

Retinoids 

Retinoid have many compounds that include: Retinol, Retinoids, Retinaldehyde, Retinoic Acid, Retinyl palmitate, Adapalene, Tazarotene, Retinyl retinoate, Isotretinoin/Tretinoin (Accutane or Roaccutane)

Vitamin A is naturally derived from beta carotene. It can be derived from both synthetic and natural forms. It has low stability when exposed to light, heat and oxygen and therefore should be applied at night time. It has the ability to penetrate through both the sebaceous glands and intracellularly. Retinoic acid is the most bioactive form. It can diffuse into the stratum corneum rapidly and then slow in pace when entering the epidermis and dermis.

How it works in the skin

Retinoids form covalent bonds with dermal protein structures altering signalling pathways. It  binds and attach to Retinoid Acid Receptors or  Retinoid X Receptors. When bound to these receptors it will regulate gene transcription which is important in tissue growth and differentiation. It regulates the epidermal proliferation and differentiation. This accelerates the shedding of corneocytes and can reduce the appearance of comedones.  The ongoing proliferation and differentiation leads to thickening of the epidermis. Retinoids up regulate collagen synthesis by stimulating the synthesis of TGF, collagen type III and fibronectin synthesis by fibroblasts. The arrangement of collagen fibres will form in a more organised and dense arrangement. Collagen type VII is also produced. Regulation of angiogenesis and the immune responses also occurs. Retinoids can have anti-inflammatory effects by inhibiting  the mass infiltration of inflammatory mediators and it can down regulate the inflammatory response of P.acnes. Retinoids have the ability to reduce pigmentary changes in the skin. Another effect retinoids have is they are antibacterial agains P.acnes. 

Who should use Retinoids?

Retinoids are suitable for photo aged skin, acne, fine rhytids, thickened and rough skin texture, vascular insufficiency, thin skin, melasma, post inflammatory Hyperpigmentation, psoriasis and dermatitis and rosacea. 

Contraindications to Retinoids

- Pregnancy and breast feeding

- Retinol based products must be ceased 3 days prior and after chemical peel procedures

- Severe liver disorders

- Photosensitising medication