Mom with Alzheimer's got Zyrtec pills; patients can't have own meds. What action should I expect from the home?

Thank you so much for answering. Sadly there are no other visitors. That's why I think it might have been a well meaning friend of another resident and then that resident gave them to mom. Mom is very anti-med. She'll proudly tell you that she doesn't take any medication even though she gets meds twice a day. Another possibility is that she (or another resident) got them off the medication cart - but very unlikely for many reasons. I'm very concerned about the danger and frankly hurt that they would think that I would endanger my mom and other residents like this. I'm supposed to meet with them this afternoon and not sure how to handle this.

Are there other visitors? Often a well meaning friend will pick these items up for the patient. They don't understand the danger, the possible drug interactions, or the law requiring written MD orders for ALL meds, Rx or non Rx.
We do check mom's room for OTC meds and confiscate them. During Flu season it becomes a real nightmare for the facility.