Final answer:
Alcohol is the most commonly used antiseptic for routine blood draws.
Step-by-step explanation:
The most commonly used antiseptic for routine blood draws is alcohol. Alcohols, such as ethyl alcohol (ethanol) and isopropyl alcohol (isopropanol), are frequently used as disinfectants and antiseptics. They work by rapidly denaturing proteins and disrupting membranes, which inhibits cell metabolism and leads to cell lysis.