Which skin areas should be avoided when applying transdermal patches?

Which skin areas should be avoided when applying transdermal patches?

• A. Face
• B. Palms of hands
• C. Elbows, below the knees, or any skin folds
• D. Upper arms

Answer: (C)

Transdermal patches deliver medication through the skin, so choosing a site with smooth, intact skin and minimal movement is essential for steady absorption and good adhesion. Areas with skin folds, creases, or frequent bending—such as elbows, behind the knees, or any skin fold—pose problems because the patch can wrinkle, lift, or become occluded. That changes how much drug actually gets through the skin and can lead to under- or over-dosing, and the patch may not stay in place. For this reason those regions are avoided. In contrast, sites that are flat, dry, and not frequently flexed (like the upper arm, chest, or back) are preferred and allow the patch to adhere well and deliver medication consistently.

Transdermal patches deliver medication through the skin, so choosing a site with smooth, intact skin and minimal movement is essential for steady absorption and good adhesion. Areas with skin folds, creases, or frequent bending—such as elbows, behind the knees, or any skin fold—pose problems because the patch can wrinkle, lift, or become occluded. That changes how much drug actually gets through the skin and can lead to under- or over-dosing, and the patch may not stay in place. For this reason those regions are avoided. In contrast, sites that are flat, dry, and not frequently flexed (like the upper arm, chest, or back) are preferred and allow the patch to adhere well and deliver medication consistently.