5-Fluorouracil (5-FU) is very effective in the treatment of actinic keratoses (AKs). It inhibits RNA and DNA synthesis and destroys hyperproliferative AKs. However, it leads to severe erythema, local irritation, edema, and discomfort during almost all the treatment and post treatment period, from 4 to 8 weeks.

Glycolic acid with 5-fluorouracil is an especially effective combination to treat actinic keratosis. It has been used in pulses of 70% glycolic acid immediately before the application of 5-FU weekly for 8 weeks. It combines the keratolytic and therapeutic effect of the glycolic acid with the efficacy of the 5-FU, the golden standard treatment of actinic keratosis, without the usual morbidity associated with the use of 5-FU alone in a non-pulse dosage (Marrero and Katz 1998).

This is a combination of a 20% SA that is a beta-hydroxy acid with a 10% mandelic acid, an alpha hydroxy acid. SA, which is lipophilic, penetrates active acne lesions quickly, while the mandelic acid that is one of the largest AHAs penetrates the epidermis more slowly and uniformly, which is ideal for sensitive skins. It is especially useful for ethnic skin because it prevents PIH. The main indications are acne, post-acne scars, and dyschromias, including melasma (Garg et al. 2008).

Mandelic acid is suitable for skins that are sensitive to the other AHAs. Its molecule is big, and so its penetration is very slow, causing no burning or stinging. Skin feels soft. It has a good capacity of neocollagenesis, increasing elastin fibers and GAGs on the papillary dermis. Besides, it has antibacterial and seborregulatory activities. The best vehicles are gel or mask.

It is a safe peel with comparable results with glycolic acid for the treatment of melasma but better tolerated and more suitable for Indian skin (Sarkar et al. 2016).

Many different combinations are possible. The final formulas will depend on the pharmacological knowledge of the performing physician, the indication of the peeling agent, and the patient. Some of the possible peeling agents are listed below:

When done properly, superficial peelings are safe, and side effects and complications are rare.

Redness is common and may last for several days.

Mild peeling is desirable and the patient must be aware of it.

Hyperpigmentation is rare and may be caused by undesired deepening of the peeling agent. It is treated with bleaching products and sun protection.