How long/how many days does it take for 0.25 mg doses of xanax (alprazolam) to start taking affect and make one feel relaxed, calm, and less anxious?

Xanax (alprazolam): Xanax (alprazolam) is a short acting sedative. The calming effect should be immediate.

Xanax (alprazolam) not working : The benzodiazepine (e.g. Xanax) naive patient should feel the effect within the hour. Individuals are unique and depending on one's pharmacogenetics/liver metabolism of medications, the medication may work for some but as well for others. The prescribing physician should be informed. More importantly, non-medicinal modalities & non-habit forming medications should be attempted first.