Reduce Acid: Prelief safely and effectively reduces the acid from foods and beverages. Prelief is the number 1 recommended brand by Urologists and Urogynecologists for the dietary management of Interstitial Cystitis. Drug Free: A good source of calcium, Prelief can be taken as often as you think you will need it; Taking 2 to 3 Prelief caplets with your food or drink can reduce the acid and minimize discomfort. Prelief is the number 1 recommended brand by Urologists and Urogynecologists for the dietary management of Interstitial Cystitis. Introduced in 1996 by developers of Lactaid and Beano, Prelief is the original product developed specifically to reduce acid from foods and drinks.