Scarring is a common cutaneous complication that occurs to varying degrees following a variety of insults to the skin including trauma, surgical procedures and dermatologic conditions(1). Although representing a natural process of wound healing and considered benign in nature, scars can lead to functional limitations and psychological distress, affecting ones self-esteem and quality of life. Although various treatment options for scars exist, none is completely satisfactory. Tretinoin cream, a derivative of vitamin A, has been widely used in the management of scars due to its ability to modulate cellular processes involved in scar formation(2). This article will review the efficacy and safety of tretinoin cream in the management of scars.
Tretinoin cream, also known as all-trans retinoic acid, is a topical prescription agent that has been used in dermatology for decades. It is a synthetic form of vitamin A, which is essential for skin health and function. Tretinoin cream works by binding to retinoic acid receptors in the skin, leading to changes in gene expression, cellular differentiation, and proliferation. These changes ultimately result in the reduction of abnormal cellular processes and the promotion of normal skin turnover and repair(2). In the context of scar management, tretinoin cream has been shown to be effective in reducing the appearance of scars, improving their texture and color, and preventing their recurrence. A number of studies have investigated the use of tretinoin cream in post-inflammatory hyperpigmentation and various types of scarring including hypertrophic scars, keloids and acne scars(1-9).
Hypertrophic scars are thick, raised scars that result from the excessive deposition of collagen during the healing process(4). They commonly occur after burn injuries, surgery, or trauma. In a randomized controlled trial, tretinoin cream was applied to hypertrophic scars twice daily for six months. The results showed a significant reduction in scar height, erythema, and pruritus compared to the control group(10). Another study, by Phan et al in 2003, found that the combination of tretinoin cream and silicone gel sheeting was more effective than silicone gel sheeting alone in reducing the height and stiffness of hypertrophic scars(6).
Keloids are similar to hypertrophic scars but extend beyond the boundaries of the original injury(7). They are more common in individuals with a genetic predisposition to scar formation and can occur after minor injuries eg following ear piercings and tatoos. In a study of 20 patients with keloids, tretinoin cream was applied twice daily for 24 weeks. The results showed a significant reduction in scar thickness, erythema, and pruritus(10). Another study found that the combination of tretinoin cream and intralesional corticosteroids was more effective than corticosteroids alone in reducing the size and firmness of keloids(11).
Acne scars are a common complication of acne vulgaris, a chronic inflammatory skin condition. They can be classified as atrophic or hypertrophic. Atrophic scars are depressed, while hypertrophic scars are raised. In a study of 60 patients with atrophic acne scars, tretinoin cream was applied once daily for six months. The results showed a significant improvement in the appearance of the scars, as assessed by both investigators and patients(11). Another study found that the combination of tretinoin cream and glycolic acid peels was more effective than glycolic acid peels alone in reducing the severity of atrophic acne scars(12).
Post-inflammatory hyperpigmentation (PIH) is a common complication of inflammatory skin conditions, such as acne, rosacea, psoriasis and eczema. It is particularly prevalent in skin of colour. In a study of 40 patients with PIH, tretinoin cream was applied at night for 12 weeks with results showing a significant reduction in the severity of the hyperpigmentation, as assessed by both investigators and patients(13).
The use of tretinoin cream in the management of scars is not without potential side effects. Common side effects include photosensitivity, erythema, dryness, and flaking(7-8). These adverse effects are usually mild and can be managed by adjusting the frequency and dose of tretinoin cream. However, in rare cases, it can cause severe skin irritation leading to blistering, crusting, and pigmentation. Patients should be advised to use tretinoin cream with caution and to seek medical attention if they experience any adverse effects.
In conclusion, tretinoin cream has emerged as a promising approach to managing scars. Its mechanism of action in promoting skin cell turnover and modulating the wound healing process makes it a logical choice for scar management. Several studies have demonstrated its effectiveness in reducing the appearance of scars, particularly in improving scar texture, color, and thickness. Although tretinoin cream is generally well tolerated, patients should be advised of potential side effects and instructed to use the cream with caution in consultation with their doctor.