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Facts about the skin from DermNet New Zealand Trust. Topic index: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z


Antiseptics

Antiseptics are chemical agents that slow or stop the growth of micro-organisms (germs) on external surfaces of the body and help prevent infections. Antiseptics should be distinguished from antibiotics that destroy micro-organisms inside the body, and from disinfectants, which destroy micro-organisms found on inanimate (non-living) objects. However, antiseptics are often referred to as skin disinfectants.

Most chemical agents can be used as both an antiseptic and a disinfectant. The purpose for which it is used is determined by its concentration. For example hydrogen peroxide 6% solution is used for cleansing wounds, while stronger solutions (>30%) are used in industry as a bleach and oxidising agent.

Antiseptic Antiseptic Antiseptic
Antiseptics

Types of antiseptics

Antiseptics can be classified according to their chemical structure. Commonly used antiseptic groups include alcohols, quaternary ammonium compounds, chlorhexidine and other diguanides, antibacterial dyes, chlorine and hypochlorites, inorganic iodine compounds, metals, peroxides and permanganates, halogenated phenol derivatives and quinolone derivatives. The following table lists some of the agents within these groups.

Group Agent Uses
Alcohols Ethyl alcohol 70%
Isopropyl alcohol 70%
Skin disinfectant
Quaternary ammonium compounds Benzalkonium chloride
Cetrimide
Methylbenzethonium chloride
Benzethonium chloride
Cetalkonium chloride
Cetylpyridinium chloride
Dofanium chloride
Domiphen bromide
Skin disinfectant
Irrigations
Eye drop preservative
Chlorhexidine and other diguanides Chlorhexidine gluconate
Chlorhexidine acetate
Pre-op skin disinfectant
Treat wounds
Bladder irrigations
Antibacterial dyes Proflavine hemisulphate
Triphenylmethane
Brilliant green
Crystal violet
Gentian violet
Skin disinfectant
Treat wounds and burns
Peroxides and permanganates Hydrogen peroxide solution
Potassium permanganate solution
Benzoyl peroxide
Wound cleanser
Gargles and mouthwashes
Irrigations
Skin disinfectant
Halogenated phenol derivatives Chlorocresol
Chloroxylenol
Chlorophene
Hexachlorophane/hexachlorphene
Triclosan
Skin disinfectant
Medicated soaps and solutions
Quinolone derivatives Hydroxyquinoline sulphate
Potassium hydroxyquinoline sulphate
Chlorquinaldol
Dequalinium chloride
Di-iodohydroxyquinoline
Treat wounds
Throat lozenges
Skin disinfectant

Uses of antiseptics

Antiseptics are mainly used to reduce levels of microorganisms on the skin and mucous membranes. The skin and mucous membranes of the mouth, nose, and vagina are home to a large number of what are usually harmless micro-organisms. However, when the skin or mucous membranes are damaged or breached in surgery, antiseptics can be used to disinfect the area and reduce the chances of infection. It is also important that people whom are treating patients with wounds or burns adequately wash their hands with antiseptic solutions to minimize the risk of cross infection.

Antiseptics are used for:

Precautions

Antiseptics bought from the pharmacy should not be used for more than one week. If the affected area has not healed or improved in that time you should stop using the antiseptic and see your doctor. Large wounds, deep cuts, burns larger than a small red spot, scrapes imbedded with particles that won’t wash away, animal bites and eye injuries should be treated by your doctor. Do not use antiseptics to treat sunburn or existing skin infections. Remember that antiseptics only reduce microorganisms on the surface of the tissue and that antibiotics will be needed to treat infection within the tissues.

People with allergies of any kind should check with a doctor or pharmacist before using an over-the-counter antiseptic product. Some antiseptics can irritate the skin and cause allergic contact dermatitis. Chlorhexidine has been reported to rarely cause anaphylaxis.

Related information

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Author: Vanessa Ngan, staff writer

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If you have any concerns with your skin or its treatment, see a dermatologist for advice.