THE GREATEST GUIDE TO IS METHADONE AN OPIATE OR AN OPIOID

[61] Like many other cardiotoxic drugs, methadone blocks the hERG K+ channel. The 2 enantiomers of methadone inhibit hERG channels with unique potency. Dextromethadone, which happens to be much less powerful being an opioid, is more potent at blocking the hERG channel with an IC50 of ~12 μM. Levomethadone has a lower affinity, with an IC50 of ~29�