Effervescent Immune Support Dietary Supplement Tablets, 10 ct, QC99902 Sale! This item is currently on backorder but you can still purchase it now and we'll ship as soon as more become available. Compare to Airborne Effervescent Tablets. Helps support the immune system. Contains 1000 mg of Vitamin C. 350 mg of herbal blend including echinacea and ginger. Excellent source of zinc and selenium. Gluten-free