American Medical Certification Association (AMCA) Phlebotomy Practice Exam 2025 - Free Phlebotomy Practice Questions and Study Guide

For a blood and alcohol test, the use of 70% Isopropyl Alcohol should be avoided because it can interfere with the results of the test. Isopropyl alcohol is commonly used for cleansing the skin prior to venipuncture to minimize the risk of contamination, but it is not appropriate for alcohol testing since it can contribute to falsely elevated alcohol levels in the blood sample.

In contrast, chlorhexidine is often used as an antiseptic in medical settings and is effective at reducing the growth of bacteria without leaving an interfering residual on the skin. Betadine, which contains iodine, is also an antiseptic that can be used for skin cleansing. Alcohol prep pads are specifically designed for skin disinfection before procedures; however, they are typically applied in situations where alcohol is not the substance being measured, such as for routine venipuncture.

Thus, avoiding isopropyl alcohol during the collection process for a blood alcohol test is crucial to ensure accurate testing results.