Alcohols (medicine)
In medicine, alcohols refer primarily to a class of organic compounds containing a hydroxyl (-OH) group attached to a saturated carbon atom. They are widely used as antiseptics, disinfectants, and solvents. The alcohols most commonly encountered in medical settings include ethanol (ethyl alcohol) and isopropyl alcohol (2-propanol).
Mechanism of Action:
Alcohols exert their antimicrobial effects by denaturing proteins and disrupting cell membranes, leading to cellular damage and death. They are effective against a broad spectrum of bacteria, viruses, and fungi, but are generally ineffective against bacterial spores. The effectiveness of alcohol is concentration-dependent, with optimal antimicrobial activity typically observed between 60% and 90% alcohol concentration in water. Higher concentrations may be less effective because they cause rapid coagulation of proteins, which hinders penetration into the cell.
Medical Applications:
- Skin antisepsis: Alcohols are used to prepare the skin before injections, venipuncture, or surgical procedures.
- Hand sanitization: Alcohol-based hand sanitizers are widely used for hand hygiene in healthcare settings and by the general public to reduce the spread of infections.
- Disinfection of surfaces and medical equipment: Alcohols can be used to disinfect non-critical medical equipment and surfaces. However, they should not be used on critical medical devices that require sterilization.
- Solvent: Alcohols are used as solvents for various medications and pharmaceutical preparations.
Advantages:
- Rapid antimicrobial action.
- Broad spectrum of activity.
- Relatively inexpensive.
Disadvantages:
- Ineffective against bacterial spores.
- Flammable.
- Can cause skin dryness and irritation.
- Volatile, leading to rapid evaporation and reduced contact time.
- Activity is reduced in the presence of organic matter (e.g., blood, pus).
- Ethanol can be intoxicating if ingested. Isopropyl alcohol is toxic if ingested.
Precautions:
- Alcohols should be used according to manufacturer's instructions.
- Avoid contact with eyes and mucous membranes.
- Flammable – keep away from open flames and sources of ignition.
- Store in a cool, well-ventilated area.
- Supervise children when using alcohol-based hand sanitizers to prevent accidental ingestion.