Benzoyl peroxide ( BPO ) is a drug and industrial chemical. As a drug used to treat mild to moderate acne. For more severe cases can be used in conjunction with other treatments. Some versions are mixed with antibiotics such as clindamycin. Other uses include bleaching flour, hair whitening, teeth whitening, and textile bleaching. It is also used in plastics industry.
Common side effects are skin irritation, dryness, or exfoliation. Use in pregnancy is an unclear security. Benzoyl peroxide exists in the family of peroxide chemicals. When used for acne it works by killing bacteria.
Benzoyl peroxide was first made in 1905 and began to be used in the 1930s. It's in the List of Essential Medicines of the World Health Organization, the most effective and safe drugs needed in the health system. Benzoyl peroxide is available as a generic drug and on the table. In the UK, 150 ml of 10% NHS cost solution is about Ã, Â £ 4. In the United States, one month maintenance cost is less than 25 USD.
Video Benzoyl peroxide
Usage
Most benzoyl peroxide is used as a radical initiator to induce polymerization. Other major applications include antiseptic and bleaching properties.
Acne Treatment
Benzoyl peroxide is effective for reducing the number and severity of acne lesions. BPO has a bactericidal effect on bacteria Propionibacterium acnes associated with acne and does not cause antibiotic resistance. This can be combined with salicylic acid, sulfur, erythromycin or clindamycin (antibiotics), or adapalene (synthetic retinoids). Two common combination medications include benzoyl peroxide/clindamycin and adapalene/benzoyl peroxide, an unusual formulation considering most retinoids are disabled by peroxides. Combined products such as benzoyl peroxide/clindamycin and benzoyl peroxide/salicylic acid appear to be slightly more effective than benzoyl peroxide alone for the treatment of acne lesions.
Benzoyl peroxide for the treatment of acne is usually applied to the affected area in gel, cream, or liquid, in a concentration of 2.5% up to 5.0%, and up to 10%. There is no strong evidence to support the idea that higher concentrations of benzoyl peroxide are more effective than lower concentrations.
Benzoyl peroxide usually causes early dryness and sometimes irritation, although the skin develops tolerance after a week or more. A small percentage of people are much more sensitive to it and tend to suffer from burning, itching, hardening, and possibly swelling. It is reasonable to apply the lowest concentrations and build the appropriate ones. Once tolerance is achieved, increasing the quantity or concentration and getting tolerance at a higher level can provide better acne leeway. Irritation can also be reduced by avoiding hard facial cleansers and wearing sunscreen before sun exposure.
Other uses
Other common uses for benzoyl peroxide include
- Whiten hair
- Teeth whitening system
- Prepare whitening flour
- As a convenient oxidant in organic chemistry
- Initiators and catalysts for polyester thermoset resins, as an alternative to the more dangerous methyl ethyl ketone peroxide.
- Hardener to start the polymerization process in the resin. For example, PMMA resins can be polymerized with benzoyl peroxide.
- Eliminate ink and dye stains on vinyl dolls and other playscale figures.
In the US, the typical concentrations for benzoyl peroxide are 2.5% to 10% for prescription drugs and over-the-counter medicines used in treatments for acne. Higher concentrations are used for hair whitening and teeth whitening. Benzoyl peroxide, like most peroxides, is a strong bleaching agent. Contact with a cloth or hair can cause permanent color loss immediately. Even secondary contact can cause bleaching; for example, contact with a towel that has been used to wash hygienic products containing benzoyl peroxide.
Maps Benzoyl peroxide
Side effects
BPO application to the skin can cause redness, burning, and irritation. These side effects are dose dependent. Skin sensitivity usually disappears after several weeks of continuous use. One in five hundred people will experience hypersensitivity and about one-third of people experience phototoxicity to UVB.
More
Benzoyl peroxide is concentrated potentially explosive like other organic peroxides, and can cause fires without external ignition. The dangers are acute for pure ingredients, so they are generally used as solvents or pastes. For example, cosmetics contain only a few percent benzoyl peroxide and do not pose a risk of explosion.
Potential carcinogenic benzoyl peroxide has been studied. A 1981 study published in the journal Science found that although benzoyl peroxide is not a carcinogen, it enhances cell growth when applied to initiated tumors. The study concludes, "caution should be recommended in the use of these and other free radical-producing compounds".
In a 1977 study using a human maximization test, 76% of subjects obtained contact sensitization against benzoyl peroxide. 5% and 10% formulations are used.
The US National Institute for Occupational Health and Safety has developed criteria for the standards recommended for workplace exposure to benzoyl peroxide.
Action mechanism
Classically, benzoyl peroxide is estimated to have tripled activity in treating acne. This is sebostatic, comedolytic, and inhibits P. acnes . In general, Acne vulgaris is an inflammation of the hormones sebaceous glands and hair follicles. Hormonal changes lead to increased production of keratin and sebum leading to clogged drainage. P. acnes has many lytic enzymes that break down proteins and lipids in sebum, leading to an inflammatory response. Free-radical reactions from the ODS can break down keratin, therefore unblocking the sebum (comedolytic). This can cause non-specific peroxidation of P. acnes, making it bactericidal, and it is thought to decrease sebum production but there is disagreement in the literature on this subject.
Anti-inflammatory
Some evidence suggests that BPO has anti-inflammatory effects as well. The micromolar concentrations of BPO prevent neutrophils from releasing reactive oxygen species (ROS) - part of the inflammatory response to acne.
Chemistry
It consists of two benzoyl groups that are bridged by peroxide bonds. The structural formula is (C 6 H 5 CO) 2 O 2 . It is one of the most important organic peroxides in terms of application and its scale of production.
Benzoil peroxide is the first organic peroxide made with intentional synthesis. It is prepared by treating benzoyl chloride with barium peroxide, a reaction that might follow this equation:
Benzoyl peroxide is usually made by treating hydrogen peroxide with benzoyl chloride.
- 2C 6 H 5 COCl H 2 O 2 2 2 2 2 O
The oxygen-oxygen bonds in peroxide are weak. Thus benzoyl peroxide easily undergoes homolysis (symmetric fission), forming free radicals:
6 = "font-size: inherited line-height: inherited; vertical-align: baseline"> 5 CO 2
The o symbol indicates that the product is radical; that is, they contain at least one unpaired electron. Such species are highly reactive. Homolysis is usually induced by heating. The half life of benzoyl peroxide is one hour at 92 ° C. At 131 ° C, the half-life is one minute.
Benzoyl peroxide is damaged by contact with the skin, producing benzoic acid and oxygen, none of which is highly toxic.
References
External links
- International Chemical Safety Card 0225
- "NIOSH Pocket Guide to Chemical Hazards # 0052". National Institute for Occupational Safety and Health (NIOSH).
- SIDS Initial Assessment Report from the Organization for Economic Cooperation and Development (OECD) Benzoyl peroxide Rezine some Organic Chemicals Hydrazine and Hydrogen Peroxide (PDF) , IARC Monograph on Risk Evaluation Carcinogenic to Humans 71, Lyon: International Agency for Research on Cancer, 1999, pp.Ã, 345-58, ISBNÃ, 92-832-1271-1 .
Source of the article : Wikipedia
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