A DRUG used to prevent malaria has been sold as ketamine at a Boomtown music festival, a drug testing group has confirmed.

Chloroquine was identified as being sold at Boomtown over the weekend with drug testing group, The Loop, advising people to seek medical help if they feel unwell.

They said the drug was being sold as ketamine and can cause diarrhoea, vomiting, skin rash and lack of appetite.

On its Facebook page, a post from The Loop said: "Chloroquine in powder form tested by TICTAC, missold onsite as ketamine, causing significant adverse effects for users. More commonly missold as cocaine due to visual likeness.

"Chloroquine is a medication typically used to prevent malaria. Common side effects include diarrhoea, vomiting, skin rash and lack of appetite.

"Symtoms of chloroquine overdose include seizures and heart palpitations. May have negative interactions with some prescription medications."

The group advised people to seek medical help or call 999 if they think they have taken it.