Regarding Transdermal Delivery Systems, how many of the following statements are correct?

• A. ALL statements are correct
• B. ONLY ONE statement is correct
• C. TWO statements are correct
• D. THREE statements are correct

Answer: (D)

Transdermal delivery systems are designed to move a drug through the skin into systemic circulation, with controlled release and without going through the liver’s first-pass metabolism. The statements in such a question are usually about what makes a drug suitable for transdermal delivery, how patches are built, and what effects or limitations they have. If three of the statements are true, while one is false, the correct choice is the one that indicates three statements are correct. In practice, you’d expect true points to include that patches deliver systemically, bypass first-pass metabolism, require drugs with suitable properties (roughly small to moderate molecular weight and appropriate lipophilicity for skin permeation), and have a defined patch structure (backing, drug-containing layer, and adhesive) with a specified wear time. Be mindful that skin irritation and absorption variability can be downsides. Without the exact statements, you can’t identify which one is false, but recognizing the common truths about patch design and function helps you confirm why three statements being correct is the right overall conclusion.