#TestIt Alert: Substance in unspecified form sold in Knoxville, TN as heroin but actually contains caffeine, diphenhydramine, an unidentified chemical, acetaminophen, and fentanyl

Heroin residue from Knoxville, TN has been found to contain caffeine, diphenhydryamine (Benadryl), an unidentified chemical, acetaminophen, and fentanyl.