It is a compound belonging to the class of retinoid and vitamin A derivatives.
It operates in many vital biological processes, it has application in dermatology due to some of its functions.
The elucidation of the molecular structure of vitamin A, in 1931, led to several investigations involving the search for synthetic chemical derivatives with the same biological activity.
With this, Sporn et al. (1976) introduced the term retinoids in the literature, to refer to all analog compounds of vitamin A, both synthetic and natural, where retinoic acid or tretinoin is included.
Retinoids participate in numerous biological processes, such as reproduction, metabolism, cell differentiation, bone development, embryogenesis, and also interfere with vision.
Retinoic acid has a molecular configuration called all-trans-retinoic acid, the consequence of which is commonly called tretinoin.
Like any other retinoid, retinoic acid initiates its biological response by connecting and activating a specific set or single receptor. They are members of a superfamily of intranuclear receptors that undergo activation by the binding of retinoic acid or its metabolites, promoting gene transcription.
In this way, through the retinoid-receptor interaction, retinoic acid initiates its actions, such as the induction of proliferation and differentiation of various types of cells during embryogenesis, as well as in the adult phase of a given individual. .
Since the 1960s, tretinoin began to be used in keratinization disorders, and its role in the treatment of acne was subsequently recognized.
In the following decade, in 1970, it also began to be used in the treatment of photoaging, demonstrating a significant reduction in wrinkles and age spots.
Isotretinoin is more effective in treating acne remission, formulations for oral use, compared to tretinoin. However, retinoic acid shows a great ability to inhibit the sebaceous secretion of acne skin in topical routes.
In high doses, retinoic acid is also used as a chemotherapy agent, due to its ability to induce cell death and differentiation. Studies have shown its effectiveness in treating diseases such as leukemia, stomach, nasopharyngeal and lung cancer.
In formulations such as creams, emulsions and gels, generally in concentrations ranging from 0.01% to 0.1%, tretinoin is indicated for the topical treatment of the signs of photoaging, including:
- Fine wrinkles
Administration of tretinoin
Tretinoin is for topical use only.
Wash and dry the affected areas carefully, at night, preferably before sleeping; apply a thin layer of tretinoin (active substance), massaging lightly in circles.
In the morning, upon waking, gently wash the areas where the product was applied and dry with a clean towel, without rubbing.
In the treatment of acne, the therapeutic action of the product can be observed after the second or third week of use, becoming more evident from the fifth and sixth weeks. In photoaging, the result of the treatment is evident after 24 weeks of use.
In both cases, after obtaining satisfactory results, continue the treatment with less frequent applications.
The frequency of application will vary from patient to patient depending on the tolerance of each skin type, and must be determined by the doctor.
Patients should be informed that over-application will not improve efficacy, and that it may increase the risk of skin irritation .
If undue irritation occurs (erythema, peeling, or severe discomfort), patients should use a moisturizer if necessary, and reduce the frequency of application or temporarily interrupt treatment.
The normal frequency of application should be restarted as soon as the irritation ceases. Treatment should be discontinued if irritation persists.
Erythema at the application site, skin exfoliation, skin pain, itching at the application site, skin irritation, skin sensitivity, burning sensation on the skin, stinging sensation at the application site and dry skin.
The cited adverse reactions occur more frequently with the use of the highest concentration of 0.1% of the cream formulation, are generally moderate and usually cease with continuation of treatment.
Hyperpigmentation of the skin, hypopigmentation of the skin, photosensitivity reaction, rash at the injection site, edema / swelling at the injection site, allergic reaction and skin atrophy.