I never did test positive for Covid even though I had a nasty cold here and there the past four years
That being said, prolonged Zyrtec use can cause depression and for 10% of people (including me) stopping cold turkey can result in extreme itchiness to the entire body
Proceed with caution
I too have never been positive for covid. I take Zyrtec every morning, in conjunction w/ plain Pepcid (famotidine) . I read about this anticovid effect via someone here a few months back. I knew about the itchiness but not the depression. Mr Cheep never got it either. He took Pepcid but no Zyrtec.
Lots of medications can cause depression in some ppl. It's something to be aware of. Sometimes things are OTC and revert to prescription, this is often the reason ( personal experience)
I don't know the answer to that. It's a good question though. Maybe someone else knows. I expect it might depend on if there were alternatives to the offending medication.