A pink/red cough medicine on a gray/black background.

Islamabad -

At least 13 people have died and dozens more have been sickened this week after drinking cough syrup apparently to get high, officials in Pakistan's eastern province of Punjab said on Friday.

The cough syrup contained dextromethorphan, a cough suppressant that is also a hallucinogen, possessing effects similar to the equine sedative and so-called date rape drug ketamine.

The patients treated over the past two days were in Gujranwala, a district 60 kilometres north of the provincial capital, Lahore. It was the second wave of deaths from apparent cough syrup abuse since just over a month ago when up to 19 people died in Lahore.

The state-run Gujranwala District Headquarters Hospital had admitted 38 men since Wednesday night and 11 had died, deputy head Gulzar Ahmad said.

“Two of the seriously ill victims referred to a health facility in Lahore also died this morning,” Ahmad said.

Ten people were still being treated and the others had been discharged. Doctors said all those affected were 20 to 50 years old and had taken massive doses.

“Many of them appear to be drug addicts though all say they just took the syrup for cough relief,” Ahmad said.

Health authorities in Punjab held separate meetings Friday over the recent deaths, an official confirmed over the phone without providing further details.

People using dextromethorphan recreationally have reported stimulant-like euphoria, particularly while listening to music. - Sapa-dpa