National Center for Competency Testing (NCCT) Medical Assistant Practice Test

What is the prefix for the drug delivery system that involves administering through the skin?

1. Trans-

2. Intra-

3. Sub-

4. Inter-

The correct answer is: Trans-

The prefix "trans-" refers to the process of crossing or going through a barrier. In the context of drug delivery systems, "transdermal" indicates that the medication is administered through the skin, allowing it to enter the systemic circulation. This method utilizes patches or gels that release the drug over time, providing a steady level of medication without the need for oral or injectable administration. The transdermal system has advantages such as enhanced patient compliance, avoidance of gastrointestinal degradation, and the potential for steady, controlled release of medication into the bloodstream. The other prefixes do not denote the same method of drug delivery. "Intra-" typically refers to within or inside, and is often used in terms like intravenous, which indicates delivery directly into the veins. "Sub-" means below or under; it is frequently related to subcutaneous injections that deliver medication just under the skin, but not through it. "Inter-" means between or among, and is not relevant to drug administration through the skin. Therefore, "trans-" is the appropriate prefix for this context.