Redoxon Immune Support Effervescent Tablets are packed with a high quality blend of nutrients to help support the immune system. Redoxon Immune Support Effervescent Tablets 30s has a Double Action formula: Vitamin C works with the white cells and acts as an antioxidant. Zinc helps maintain healthy skin and protects against free radicals. The clinically tested formula gives your body a first line defence to prevent troublesome infections such as colds, flu and fever.