Acne vulgaris is a common skin disorder characterized by non-inflammatory and inflammatory lesions on the face and the upper trunks of the patient. It affects about 70%-80% of adolescents and young adults. Patients with mild to moderate comedonal or papulopostular acne can use topical therapy as a treatment. B-hydroxilacid Salicylic acid (1-5%) can be used to treat comedonal acne in addition to topical retinoid therapy.

What is Salicylic Acid?

Salicylic acid is a component in various over-the-counter products that includes lotions, creams, alcohols-based solutions, and medicated pads and it is more preferred among traditional peeling agents. This acid is a derivative of benzoic acid that represents a carboxy-acid attached to an aromatic alcohol phenol and this acid is contained in a hydroethanol formula at 20-30% concentration. Salicylic encourages the sloughing of dead skin like keratolytic agent. It is mild, safe, and effective treatment for mild acne, oily skin, textural changes and post inflammatory hyper pigmentation. It also works on people with darker skin.

How does Salicylic Acid work?

Salicylic acid has strong comedolytic effects. It functions by dissolving the intercellular cement that binds the epithelial cells together and reduces the corneocyte adhesion. It is also an excellent keratolytic agent that exhibits some degree of percutaneous absorption and has lipophilic character facilitating the peeling of the top layer of the skin and the opening of plugged follicles, leading to the renewal of skin cell replacement cycle.

These comedones form when keratinization in the mid-section of the follicular canal becomes too excessive. Salicylic acid, being a lipophilic agent, goes into the middle of the sebaceous unit to prevent the formation of comedones. It also affects the arachidonic acid cascade and has anti-inflammatory properties useful in reducing non-inflammatory as well as inflammatory acne lesions. Salicylic acid can help unclog pores to resolve and prevent lesions, but it can do nothing about the secretion of sebum form the sebaceous gland nor does it have any effect on P. acne bacteria.

If treatment with salicylic acid is interrupted, the acne lesions that have been healed may become clogged again, resulting in the renewal of acne formation.

How Salicylic acid should be used?

The time period for application of salicylic acid is in proportion to the dose absorbed because the skin efficiently absorbs salicylic acids compared to other topical drugs. The efficiency of the absorption of the salicylic acid in the skin is dependent on the duration of skin contact and the medium of application. Some salicylic acid ointment absorbs up to 20%-25% with a few minutes of skin contact to reduce absorption (most topical drugs are left in contact with the skin for up to 12 hours). Those preparations that contain 0.5% to 10% of salicylic acid are recommended for acne treatment. In the US, up to 2% concentration of salicylic acid is permitted. Salicylic acid can also be used in children.

If salicylic acid is applied to a large surface area of the skin for a long time, salicylate toxicity may occur, even this is rare with topical applications. Taking salicylic acid orally may lead to excessive stomach irritation.

Side effects associated with Salicylic acid usage

There may be skin exfoliations and discomfort on salicylic concentrations more than 2%. The adverse reactions appear when there is a systemic use or a prolonged exposure of the skin area (toxic inner ear damage and hypersensitivity) though common side effects involve only the skin dryness. When symptoms like heavy breathing, dizziness, hearing impairment, lethargy, digestive disorders, and nausea persist, patients should consult their doctors. Pregnant women should first consult their doctors before treating acne with salicylic acid since this medicine can be absorbed through the skin. Salicylic acid is an FDA Pregnancy category C drug.

Salicylic acid therapy is proven to significantly reduce acne severity as reports of moderate to good improvements have been documented. Salicylic acid can be used with traditional acne therapy to accelerate the resolution of the comedones and inflammatory papules; its inflammatory character is also helpful for post inflammatory erythma. Caution is to be observed while using the treatment because of the rapid and efficient percutaneous absorption of the drug.