Nurses working in prisons are being hospitalised by Spice fumes, the Royal College of Nursing has warned.

The so-called “zombie drug” is so prevalent in jails that healthcare staff are treating up to 50 prisoners a week each, it claimed.

Many nurses have suffered ill-effects from breathing in fumes while helping prisoners stricken by the psychoactive substance, which is a form of synthetic cannabis.

Staff reported feeling too overcome to drive home and at least one had to be rushed to hospital by ambulance after being “knocked unconscious” by the drug.

In an RCN report released on Tuesday, one prison nurse said: “Walking back after attending to a patient, I’ve suddenly felt dizzy, nauseous – it’s almost like the world has zoomed out.

“It’s really bizarre. I’ve sat in my car in the car park for 50 minutes after work [before] I feel confident enough to drive. We’re all worried about driving in case it’s not safe or we get stopped and it shows in our system.

“If this happened in a hospital, there would be uproar and investigation after investigation. I feel like it’s being swept under the carpet. There’s not enough being done.”