Antiseptics & Disinfectants
Introduction
- Antiseptic & disinfectant connote an agent which inhibits or kills microbes on contact.
- Antiseptics are agents used on living surfaces (skin, mouth) while Disinfectants are those used for inanimate objects (instruments, privies, water supply).
- There is considerable overlap and many agents are used in either way. A practical distinction between the two on the basis of a growth inhibiting versus direct lethal action is futile because these are often concentration dependent actions. The term Germicide covers both category of drugs.
- A good antiseptic/ disinfectant should be:
– Chemically stable
– Cheap
– Nonstaining with agreeable colour and odour
– Cidal and not merely static, destroying spores as well
– Active against all pathogens-bacteria, fungi, viruses, protozoa
– Require brief time of exposure
– Able to spread through organic films and enter folds and crevices
– Active even in the presence of blood, pus, exudates and excreta - A disinfectant in addition should not corrode or rust instruments and be easily washable.
- An antiseptic in addition should be:
– Rapid in action and exert sustained protection
– Nonirritating to tissues, should not delay healing
– Nonabsorbable, produce minimum toxicity if absorbed
– Nonsensitizing (no allergy)
– Compatible with soaps and other detergents
Classification
Antiseptics & disinfectants are classified as follows:
1. Phenol derivatives
- Phenol
- Cresol
- Hexylresorcinol
- Chloroxylenol
- Hexachlorophene
2. Oxidizing agents
- Pottasium permangnate
- Hydrogen peroxide
- Benzoyl peroxide
3. Halogens
- Iodine
- Iodophores
- Chlorine
- Chlorophores
4. Biguanide
- Chlorhexidine
5. Quaternary amines
- Cetrimide
- Benzalkonium chloride
- Dequalinium chloride
6. Soaps
- Sodium & Pottasium salts
7. Alcohols
- Ethanol
- Isopropanol
8. Aldehydes
- Formaldehyde
- Glutaraldehyde
9. Acids
- Boric acid
- Acetic acid
10. Metallic salts
- Merbromin
- Silver nitrate
- Silver sulfadiazine
- Mild silver protein
- Zinc sulfate
- Calamine
- Zinc oxide
11. Dyes
- Gentian violet
- Acriflavine
- Proflavine
12. Furan derivative
- Nitrofurazone
