You could call your doctor, or check out drugs.com, and click drug interactions.
If the SAME doctor prescribed all three of the medications for you, and did not warn you about taking them together, it's safe to assume you can.
Since you are concerned about the safety of taking the alprazolam with the other meds, either call the prescribing doctor or your pharmacist who can tell you if there are any interaction warnings about these drugs.
Taking the Xanax without the reassurance from your doctor or a pharmacist will do nothing but increase your anxiety.
You are very smart to ask!
Peace
Greenlydia
When I googled the drug from your other post it did mention a warning about taking medications for mental illness, so I'd ask about this.