Today, we announced the issuance of seven warning letters to companies illegally marketing products containing 7 hydroxymitragynine (7 OH). https: www.fda.gov news events press announcements fda issues warning letters firms marketing products Kratom and 7 hydroxymitragynine or 7 OH are two types of substances that have been gaining attention recently. But what exactly are they? Kratom is considered an herbal supplement that can have effects similar Trend Alert: 7 OH Kratom And 7 OH Vape Life destroying addiction can start at a corner store Michigan Medicine