I’d say it helped for 2.5 weeks or so then wore off. I could do a lot more than I normally can and more consistently while I was on the antihistamine.
2-3 hours a day of work at one point for 7 days in a row during the holidays. Also, I was helping out with lots of questions from customers and tourists (I work in the tour industry).
Sadly, it seemed to wear off last week.
My doctor said I could bump it up to 20mg daily.
I feel better today. Not great, but much better than yesterday.