Washington University in St. Louis (WU)
The urine screen of PCP (phencyclidine) is prone to false positive results with certain commonly used medications, such as diphenhydramine (Benedryl), dextromethorphan (cough suppressant in OTC cough medicines with “DM” in the name, and tramadol (Ultram). Our goal is to find if such a correlation exists and the false positive rate.