Figure 4 Panel A shows mean data (n  =  11) from three items of the modified version of the Hughes‐Hatsukami Withdrawal Questionnaire, while panel B shows mean data from four items of the modified Tiffany‐Drobes Questionnaire of Smoking Urges (QSU) before (Pre) and after (Post) a waterpipe use episode (mean duration 45.9 minutes) that followed 24 hours of carbon monoxide‐verified tobacco abstinence (items in both scales were presented to participants in Arabic). The actual QSU items were: “I have a desire for a waterpipe right now”, “If it were possible, I probably would smoke now”, “All I want right now is a waterpipe”, and “I am going to smoke a waterpipe as soon as possible”. The Y axes show the total score for each item; filled symbols indicate a significant pre‐post difference (p < 0.05).