Why not use nicotine patches below the waist?

Nicotine patches are designed for transdermal delivery through the skin, primarily on areas with a higher concentration of blood vessels, such as the upper body or arms. Using them below the waist may lead to inconsistent absorption due to lower blood flow and varying skin thickness. Additionally, the patches could be more prone to friction and movement in lower body areas, potentially reducing their effectiveness. It's generally recommended to follow the manufacturer's guidelines for optimal results.