Can i take xanax (alprazolam) with phentermine?

Yes: There are no known interactions between the 2, but both are schedule i'v drugs which means they have some potential for abuse/dependence and are not indicated for long term usage.

Downers and uppers: While not an interaction the combo is a dangerous path. Phentermine used to diet causes anxiety, taking a tranquilizer, xanax (alprazolam) to counter the anxiety is not logical and can lead to escalating pattern of drug use. Sedatives by calming may reverse any benefit from the diet pills. If the diet pill causes so much anxiety that you need another med to counter it, its not worth taking. Se