From herbs to probiotics, a number of natural remedies are popular among people who suffer from eczema (a skin condition estimated to affect more than 30 million Americans. One lesser-known natural treatment said to ease eczema is Phellinus linteus, a medicinal mushroom long used in traditional Chinese medicine. Like many medicinal mushrooms, Phellinus linteus is thought to stimulate the immune system as well as curb inflammation. So far, there’s not much scientific support for the claim that Phellinus linteus can help control eczema flare-ups. Still, a 2012 study from BMC Complementary and Alternative Medicine suggests that Phellinus linteus may help alleviate eczema by lowering levels of immune cells involved in triggering eczema-associated inflammation.