Pictorial health warning labels on the waterpipe device are effective in reducing smoking satisfaction, puffing behaviour and exposure to CO: first evidence from a crossover clinical laboratory study.

This pilot study shows that placing HWL on the WP device is effective in reducing WP smoker's positive experiences, puffing parameters and exposure to carbon monoxide. HWLs lead also to more appreciation of WP harmful effects, making them a promising regulatory approach for addressing the spread of WP smoking among young adults in the USA.