An ITV News investigation has revealed emergency services are spending an increasing amount of time giving medical care to people who have taken the drug Spice.
As the NHS comes under increasing pressure, those on the front line say that patients who have overdosed on Spice can be aggressive, and have symptoms that are difficult to treat.
ITV cameras spent a night with an ambulance crew in Cardiff City centre.
This footage shows the moment they were called to help someone who had used Spice.
In just three years the Welsh Ambulance Service said they have seen the number of Spice-related ambulance call-outs increase by 1500%.
Watch the full report:
- What is Spice?
Spice is a chemical that is sprayed onto dried herbs or plants. Because of how it is made the strength can vary hugely from one batch to the next.
Experts say the drug has become stronger since it became illegal two years ago. Some of the short-term side effects include seizures and vomiting.
But it is still a relatively new drug - and the long-term effects of using it are still unknown.
'James' - not his real name - lives in Carmarthenshire. He started smoking Spice after his partner took his own life.
He stopped using it two years following an overdose - but still has regular seizures.
For Christina, Spice is a way of life. She said it is a popular drug among the homeless community because it is strong and cheap.
She has been smoking it for four years, and said she has seen it affect people in different ways.
See more on this investigation by Hannah Gamlin on Wales at Six tonight.