Which antiseptic should not be used for injection preparation?

• A. Alcohol
• B. Chlorhexidine
• C. Iodine
• D. Hydrogen peroxide

Answer: (A)

Alcohol should not be used for injection preparation because mucous membranes and tissue around injections are sensitive to it. It can cause burning, drying, and chemical irritation, and it evaporates quickly, which limits contact time and antimicrobial effect. In this setting you want an antiseptic that is gentle on tissue and provides lasting antimicrobial activity. Chlorhexidine or povidone-iodine fit that role, offering broad-spectrum coverage with better tissue compatibility. Hydrogen peroxide can be cytotoxic to cells and delay healing, so it’s not ideal for mucosal surfaces either, while iodine is effective but can cause staining or irritation in some patients. So, alcohol is avoided for injection prep due to its irritating nature and lack of sustained activity.