<P> Allium cepa, the common onion, is the active content of Mederma . Onions contain a readily available and highly researched bioflavonoid with antihistamine and antiproliferative effects on both normal and malignant cells . </P> <P> Water (purified), PEG - 4, Aloe barbadensis leaf juice, Allium cepa (onion) bulb extract, xanthan gum, allantoin, methylparaben, sorbic acid, fragrance . </P> <P> Merz Pharmaceuticals also produces Contractubex for scars, which also contains onion extract in addition to other ingredients . Contractubex has been found effective in clinical trials for the prevention of hypertrophic scars and keloids in Chinese patients having laser tattoo removal . </P>

What is mederma and how does it work