Hi,
Did you tell your doc that the claritin doesn't work well without the atarax? You may have to explain that to him. You could try a zyrtec in place of the claritin, or even a benedryl, benedryl is sedating though. They are all are H1's.
As far a the zantac, I felt the same way you did when I was put on it. I thought what the heck, why in the world...It is because zantac is an H2 blocker! It works at blocking histamines in the stomach. Histamines are what causes the mast cells to open up. So the zantac is working to block histamines in foods.
It is possible that the singular is making you tired, that should subside, It gave me strange dreams, should have wrote them down and wrote a book!
I think that you have a good combination. A lot of us on here are taking a couple of different H1s. For instance I take claritin in the morning and Allegra in the late afternoon. Remember though with mast cell issues less is best. In other words if you don't need it don't take it! A lot of us react to inactive ingredients so you have to be careful with that.
Also it is best to start/change one med at a time. That is the only way to see if a med is a problem for you.
You can get a lot of information here on the forum. I think I have learned more from the forum than the doctors-after all we are the patients!
Under medicines there is a post about medicine combinations-I think it is under my masto mix or something of that nature!
Good luck!
Pam