Over the counter acne treatments are available to buy without a prescription. Most of these products will contain benzoyl peroxide, salicylic acid, retinol or alpha hydroxy acids (AHAs) either alone or in combination. They can be helpful for mild acne, but will not work in all cases and are unlikely to help moderate or severe acne.
Benzoyl peroxide kills bacteria that contribute the formation of acne lesions and helps to prevent excessive skin cell division and clogging of hair follicles with dead skin cells. It is available in concentrations of 2.5-10%. It can cause dryness and irritation of the skin particularly when high concentrations are used.
Salicylic acid removes dead skin cells preventing the openings of hair follicles ‘pores’ from becoming blocked.
Alpha hydroxy acids (AHAs) encompass a wide range of products but the most widely used are glycolic acids and lactic acids. AHAs help to remove dead skin cells and reduce inflammation.
Retinol is chemically related to retinoids, which are frequently used prescription products for acne. It works in a similar manner reducing the production of sebum and regulating the division of skin cells (keratinocytes) to reduce blockage of hair follicles.
All of these products can be irritant particularly if you have sensitive skin. If you have mild acne and have not used any topical treatment then a product containing a low concentration of benzoyl peroxide is generally a good starting point. If over the counter products are proving ineffective it is usually better to see a doctor in order to obtain more effective prescription topical or oral treatment.