I have been taking cetirizine at night to help me sleep, but I have chronic muscus buildup in my throat for almost 2 years, have been through 5 different test they show nothing. Is it ok to take this to help me sleep, this is the only medicine I am on, I have Fibromyalgia was on Neurotin and Trazadone, been taking for 6 or 7 years I have heard that Benedryl may cause Dementia