Allergist wants me on xyzal (levocetirizine) for allergic reactions/chronic hives. Neuro wants me on amitriptyline for migraine. Take both? Start one then other?

Drugs interaction. Combination might increase risk of of CNS depression and side effects of amytriptyline but it is usually safe when you start with a low dose of Amitriptyline and increase as tolerated. Please have your doctor monitor your symptoms.