Ive been on every antihistamine, OTC & Rx. Ive tried every sunblock. Ive even been on XOLAIR for 6 months, but stopped because i wasnt getting much relief from it. so im going back to antihistamines, but no matter which one i use, it knocks me out! l cant function. my doctor told me to take montelukast sodium with zyrtec. if i take these at night, will they still be as effective the next day? will i still be drowsy all day? Do you have any other ideas for me to use to combat my solar urticaria?