Monoamine Oxidase Inhibitors prevent the breakdown of neurotransmitters like dopamine and/or serotonin (depending on the type of MAOI.) As a result, dopamine/serotonin levels can become dangerously high if an MAOI is combined with drugs that release dopamine/serotonin (such as MDMA.)
Never combine MDMA with an MAOI. There are some possible exceptions to this rule, but unless you're absolutely sure you know what they are, avoid the combination.
Never combine MDMA with an MAOI. There are some possible exceptions to this rule, but unless you're absolutely sure you know what they are, avoid the combination.