The drug which hospitalised six people in Cork earlier this week has been identified as a highly potent and potentially lethal psychoactive drug, with the street name N-Bomb.
A stimulant with hallucinogenic effects, it is a controlled drug under Irish law.
The World Health Organization has reported a number of deaths from the drug in other countries, including Australian, Britain and the United States.
Correctly known as 251-NBOMe, it is a derivative of the 2C family of psychedelic phenethylamine designer drugs which also includes 2C-B and 2C-P.
One of the six students understood to have taken the drug at a house party in Greenmount in Cork city on Tuesday, remains in a critical condition in hospital.
The five others, four men and one woman, have since been discharged from hospital.
A file is being prepared for the Director of Public Prosecutions on a 29-year-old man who was questioned in relation to the incident.
He was arrested in the French's Quay area of the city and questioned for ten hours before being released without charge yesterday.
Scientists from Forensic Science Ireland confirmed the analysis having tested two samples of white powder found by investigating gardaí.
Speaking on RTÉ's Morning Ireland, President of the Union of Students of Ireland Kevin Donaghue said many young people take drugs without knowing what is in them, which is a big danger.
Mr Donaghue said 80% of students surveyed admit to having taken drugs and 95% said they had shared drugs with someone else.
He said a number of student unions have undertaken a project called "What’s in a Pill" to inform people of the dangers of drugs with less focus on not doing drugs as that does not work.
He said it is looking at what is in drugs and much of the project focuses on what to do in an emergency.
HSE updates drugs warning
In a statement, the HSE has updated its warning to members of the public after the incident in Cork.
Specifically, the warning relates to the 2C family of psychedelic phenethylamine designer drugs.
According to the HSE, these include 2C-B, 2C-P, 2C-I and its derivative 25I-NBOMe. These drugs are also known by their street names which include N Bombs, Smiles, Solaris, 25-I, INB-Meo and Cimbi-5.
"These drugs can be sold in liquid, powder and tablet," the statement said.
"Young people are advised that there is no quality control on these drugs. There are problems with purity and contaminants, and there is no way of checking that what is purchased or consumed is the intended substance.
"Given the serious side-effects experienced by the young people in Cork, the HSE Addiction services are issuing a warning about possible contaminated 'party pills' and advise people not to consume any unknown substances that they are offered at this time."