Antiseptics
Outline the pharmacology of antiseptics and disinfectants
Key Definitions
Relevant definitions for antiseptics include:
- Cleaning
Physical removal of foreign material.- Used for non-critical items, which come into contact with healthy skin but not mucous membranes (e.g. blood pressure cuff)
- Decontamination
Destruction of contaminants such that they cannot reach a susceptible site in sufficient number to cause harm. - Disinfection
Elimination of all pathological organisms, excluding spores.- Used for semi-critical items, which are those that contact mucous membranes but do not break the blood barrier (e.g. endoscopes, laryngoscopes)
- Sterilisation
Elimination of all forms of microbial life, including spores.- Used for critical items, which are those that enter sterile or vascular tissue and pose a high risk of infection (e.g. surgical instruments, vascular and urinary catheters)
Antiseptic Agents
| Drug | Isopropyl Alcohol | Chlorhexidine | Povidone iodine |
|---|---|---|---|
| Pharmaceutics | Typically 60-90% - requires some water to denature protein. Flammable. | May be aqueous or combined with isopropyl alcohol. | Iodine combined with a polymer (povidone) to enhance water solubility |
| Antiviral Properties | Poor antiviral | Poor antiviral | Good antiviral |
| Antibacterial Properties | Broad spectrum antibacterial | Broad spectrum antibacterial and antifungal | Broad spectrum including fungi, spores (unlike iodine), and tuberculosis |
| Toxic | Irritant on mucous membranes and open wounds | Hypersensitivity | Hypersensitivity |
| Other | Persistent antiseptic effect | Requires continual release of iodine to achieve effect. Inactivated by organic substances. Stains. |
References
- Petkov V. Essential Pharmacology For The ANZCA Primary Examination. Vesselin Petkov. 2012.
- Sabir N, Ramachandra V. Decontamination of anaesthetic equipment. Continuing Education in Anaesthesia, Critical Care and Pain. (2004). 4(4), 103–106.