Benzoyl peroxide

Absorption

In a sample of excised skin, 1.9% of a radiolabelled topical dose fully penetrates the skin, and 2.6% remains in the skin. The radiolabelled dose that fully penetrates the skin is recovered as benzoic acid, while the dose in the skin is approximately half benzoic acid and half benzoyl peroxide. 95.5% of a radiolabelled dose is not absorbed or metabolized after 8 hours.

Toxicity

Data regarding overdoses of benzoyl peroxide are not readily available. During an overdose patients may experience and increased risk or severity of adverse effects such as skin itching, burning, peeling, inflammation, and erythema.
The oral LD50 in rats is 490 mg/kg.

Description

Benzoyl Peroxide may affect workers in the electronics and plastics (epoxy resins and catalysts) industries, electricians, ceramic workers, dentists and dental technicians, laboratory technicians and bakers. As it was contained in candles, it also induced contact dermatitis in a sacristan. However, some positive tests are of unknown occupational relevance.

Description

Benzoyl peroxide is a bleaching agent commonly found in acne treatments, hair coloring, and teeth whitening products. On the skin, it forms benzoic acid and oxygen, but it is used in large volumes to initiate polymerization in expandable styrene and other resins.

The Uses of Benzoyl peroxide

Benzoyl Peroxide is a widely used organic compound of the peroxide family. It is used as a source offree radicals in many organic syntheses andto initiate polymerizations of styrene, vinylchloride, vinyl acetate, and acrylics; to curethermoset polyester resins and silicone rubbers;in medicine for treating acne; and forbleaching vegetable oil, cheese, flour, and fats.

The Uses of Benzoyl peroxide

A mixture of the SM (100 g, 497 mmol), NBS (88.5 g, 497 mmol), and AIBN (10 g, 50 mmol) in CCl4 (700 mL) was stirred at reflux for 12 h. The mixture was cooled to RT, diluted with H2O, and extracted with EtOAc. The org layer was separated, dried (Na2SO4), and concentrated. The residue was purified by silica gel flash chromatography to provide the product. [48 g, 42%]

Indications

Benzoyl peroxide is formulated with antibiotics such as erythromycin and clindamycin for the treatment of acne vulgaris. Benzoyl peroxide is formulated as a number of topical products for the treatment of acne. Benzoyl peroxide is also indicated in combination with tretinoin for the treatment of acne vulgaris in patients aged nine years and older. A triple-combination therapy including both clindamycin and adapalene is also available and indicated for the treatment of acne vulgaris in patients ≥12 years of age.
Topical benzoyl peroxide is also indicated for the treatment of inflammatory lesions of rosacea in adults.

Background

Benzoyl peroxide is a commonly used drug in topical treatments for acne. It has been formulated as products with either a single active ingredient, or with erythromycin, clindamycin, or adapalene. After administration, the peroxide bond is cleaved, allowing benzoyloxy radicals to nonspecifically interact with proteins. This treatment decreases keratin and sebum around follicles, as well as increasing turnover of epithelial cells.
Benzoyl peroxide, in combination with erythromycin, was granted FDA approval on 26 October 1984.

Pharmacokinetics

Benzoyl peroxide is a topical treatment for acne that generates free radicals to break down comedones and increase the rate of epithelial cell turnover. It has a short duration of action as its active free radical metabolites quickly react to form inactive metabolites. The therapeutic index is wide, as overdoses are rare, however patients may still experience skin peeling. Patients should be counselled regarding increased risks of skin irritation, dryness, and sunburn.

Metabolism

The peroxide bond of benzoyl peroxide is cleaved to form 2 benzoyloxy radicals. The benzyoyloxy radicals may interact with other molecules, forming benzoic acid; alternatively, benzoyloxy radicals can break down further to release carbon dioxide and a phenyl radical.