"Some lip products contain salicylic acid, an ingredient of unproven safety when applied to lips. The FDA-approved uses of salicylic acid are the application to hypertrophied skin lesions, such as corns, calluses, and warts. Salicylic acid possesses a keratolytic action that erodes the hyperkeratotic lesions. However, lips are not hyperkeratotic skin, as found in warts. When salicylic acid is applied to the lips, it can erode through the outer stratum corneum to damage living skin layers beneaththis creates a vicious cycle.
The cycle begins when a patient with a minor case of chapped lips uses a salicylic acid lip product. These products often contain minor analgesics to mask the discomfort so that the patient's lips feel soothed. However, the salicylic acid causes de novo damage to the lips. When the product's analgesic effect abates, the patient perceives the new damage as a continuation of the chapped lips and uses the product again. Eventually, the patient becomes dependent on the analgesic effect of the product to combat its continuing damage to the lips, causing extended use of the product for sustained periods, possibly decades. The remedy is to stop application of the product entirely, in the hope that the damaged lips will eventually heal, replacing it with a nonirritating protectant/hydrocortisone product in the interim, if desired.
Even lip balms that do not contain salicylic acid may contain potential irritants and/or allergens. These nonprotectant ingredients include isopropyl myristate, eugenol, and phenol.
