Vitamin C

I am taking the Vista Vitamins which I highly recommend! they are excellent. I want to also add some more vitamin C and I'm wondering if there is a better form to take for absorption? I have bad allergies and sinus issues and when I supplement extra Vitamin C I don't have near the same amount of problems. I see significant improvements! Is a liquid vs a pill or brand better? Anyone know? Thanks!

I take the chewable variety from GNC. They work well for me. Carolyn

I take extra C. I get a big bottle of chewables at Costco - the Kirkland brand.