Dear Slew Chong, I recommend AHCC, which is a much-tested and much-praised blend of five medicinal mushrooms, in an extract of rice bran. The original formula comes from Japan. Here in the USA, I buy my AHCC from the Vitamin Shoppe. I take a capsule every third day, as part of my cancer-prevention plan. Their website is: http://www.vitaminshoppe.com. It's product # VS-2191. I will keep your son in my prayers. Blessings, Owen Http://owen.curezone.com/