The various sensations of withdrawing from heroin can be likened to being in the grips of a particularly bad case of the flu, which has led to the slang term “super flu” being used to describe the withdrawal stage.

These symptoms are not life-threatening in and of themselves (unlike withdrawing from alcohol, for example, which can be fatal on its own), but they might induce a user to take heroin or other dangerous substances to alleviate the physical and mental distress. That action might be lethal, especially if the user takes too much of the drug in order to compensate for how debilitating the withdrawal effects can be. In addition to the physical effects of heroin withdrawal, addicts also experience feelings of loneliness, despair, and a desperate compulsion to use the drug again, making them especially prone to making an ill-advised decision.

Heroin withdrawal symptoms usually kick in around 12 hours after the user has their last dose of heroin. They tend to peak around one to three days later and gradually subside between five and seven days after they first arose, although some symptoms may persist, albeit in milder forms. In cases of extreme heroin abuse (either in terms of volume consumed or duration of abuse), it may take weeks, or even months, for the withdrawal effects to fully subside, a condition known as post-acute withdrawal syndrome.