Warning: This video contains descriptions of drug-taking and distressing images
A new wave of synthetic drugs is sweeping across the United States, raising fear of a worsening drug crisis.
Earlier this year, President Donald Trump pledged a crackdown on drug cartels, proscribing many as terrorist organisations.
Drug overdose deaths have fallen from a peak of around 110,000 in 2022, down to roughly 70,000 last year.
However, America's decades-long drug crisis may be accelerating and authorities are increasingly concerned about cheaper, more powerful synthetic drugs, including an animal tranquilliser called tranq.
The BBC's Quentin Sommerville reports from the frontlines in South Side, Chicago, where communities are battling the crisis.
Camera journalist: Darren Conway