Xanax (alprazolam) is a benzodiazepine often prescribed for "situational anxiety," such as a fear of flying, and it is a powerful sedative that can certainly induce sleep. However, using it specifically as a sleep aid on a flight comes with significant caveats. First, you should never take Xanax for the first time on a plane; you need to know how your body reacts to it in a safe environment first. Second, mixing Xanax with alcohol (even one glass of wine) is extremely dangerous and can lead to severe respiratory depression or "blackout" behavior. On a plane, there is also the risk of "Deep Vein Thrombosis" (DVT); because Xanax induces such a deep, unmoving sleep, you may not shift your legs for hours, increasing the risk of blood clots. Furthermore, if there were an emergency, being heavily sedated would impair your ability to react or evacuate. If you have a prescription, follow your doctor's advice strictly. If you don't, safer alternatives for "airplane sleep" include melatonin, magnesium, or over-the-counter antihistamines, which carry fewer risks of dependency and extreme disorientation upon landing.