How salicylic acid can be used to treat acne

Salicylic acid a commonly used peeling agent used to treat patients with mild to moderate comedonal or papulopustular acne. It is a derivative of benzoic acid and can be used in combination with topical retinoid therapy.

Formulations

It is a component in various over the counter acne products including lotions, creams, alcohol based solutions and medicated pads at a 20%-30% concentration.

Mechanism of action

Comedones are formed due to excessive keratinization in the mid section of the follicular canal. Salicylic acid is an excellent keratolytic agent i.e. it encourages the sloughing of dead skin cells. It does this by dissolving the intercellular cement that binds the epithelial cells together leading to the reduction in the cell adhesion. Salicylic acid also has a lipophilic character that facilitates the peeling of the top layer of skin and the opening of plugged follicles, which leads to a renewal of the skin cell replacement cycle. Thus, salicylic acid has a strong comedolytic effect.

Salicylic acid affects the arachidonic acid cascade and has anti inflammatory properties also. Hence, it is useful in reducing both non-inflammatory as well as inflammatory acne lesions.

Method of use

Its efficacy depends on the duration of skin contact and the medium of application. It has been seen that some salicylic acid ointment led to a 20%-25% of absorption. While most of the topical drugs are left on the skin surface for 8-12 hours, preparations containing salicylic acid should be taken off after a few minutes so as to reduce the amount of absorption. Preparations which have a concentration of .05%-10% of salicylic acid are recommended for use in acne treatment.

Advantages

1) Salicylic acid can be used in case of children.
2) Absorption of salicylic acid in the skin is more efficient compared to other topical drugs.
3) It is a safe and effective treatment for mild acne, oily skin, textural changes and post inflammatory hyper pigmentation and in people with darker skin.

Disadvantages

1) Salicylic acid cannot affect the secretion of sebum from the sebaceous gland or have any effect on the P.acnes bacteria.
2) Salicylic acid must be used continuously even after the acne lesions have been healed as a maintenance therapy, because if application is stopped the pores become clogged once again and there is renewal of acne formation.
3) Salicylic acid is n FDA Pregnancy Category C drug so women who are pregnant should consult their doctors as this medicine can be absorbed through the skin.
4) It should be kept in mind that though systemic toxicity is a rarity with topical application, if the drug is applied to a large surface area of the skin for a long time, there may be occurrence of salicylate toxicity.
5) Salicylic acid is not to be taken orally as it leads to excessive stomach irritation.

Side effects associated with salicylic acid usage

1) All preparations with concentrations greater than 2% there may be exfoliation of skin and discomfort.
2) The most common side effect is dryness of skin which is usually mild.
3) If it is used over a large area for long, systemic absorption can lead to inner ear damage and hypersensitivity.
4) Other side effects like heavy breathing, dizziness, hearing impairment, lethargy, digestive disorders, and nausea.

Conclusion

Salicylic acid has been proven to significantly reduce acne severity and most patients report moderate to good improvement with this therapy. Salicylic acid peels can be used alongside traditional acne therapy to speed up resolution of the comedones and inflammatory papules. However, due to rapid and efficient percutaneous absorption of the drug, it is wise to take a cautious approach while using this drug.