Nearly 400,000 deaths from 1999-2017 involving opioids can be divided in three distinct waves

1: The first wave began with increased prescribing of opioids in the 1990s, with overdose deaths involving prescription opioids (natural and semi-synthetic opioids and methadone) increasing since at least 1999.

2: The second wave began in 2010, with rapid increases in overdose deaths involving heroin.

3: The third wave began in 2013, with significant increases in overdose deaths involving synthetic opioids – particularly those involving illicitly-manufactured fentanyl (IMF). The IMF market continues to change, and IMF can be found in combination with heroin, counterfeit pills, and cocaine.

Source: CDC.GOV