The College of Psychiatrists says the substance is leading to a rise in young people seeking addiction services.
Doctors are urging the Government to ban the distribution and sale of a a strain of semi-synthetic cannabis.
HHC is currently legal in Ireland and is found in vapes and edibles.
The substance has led to an increase in the number of young people attending addiction services according to the College of Psychiatrists.
They also found cases of young men suffering from psychosis as a result of smoking HHC vapes.
Garrett McGovern, Clinical Lead of HSE Addiction services in the Midlands, Louth, Meath, says banning isn't the answer: