Severe Kratom Withdrawal Induced by Oral Naltrexone: A Case Report and Call for Increased Awareness

Background: Kratom is an illicit substance that has binding affinity to opioid receptors in high doses. Naltrexone is an opioid antagonist used for treatment of alcohol dependence; however, a 7- to 10-day washout period is required to avoid severe withdrawal in opioid users. There is currently no warning regarding concurrent kratom use in naltrexone prescribing information.