Cocaine in Ireland often mixed with ‘parasitic worm medicine’

Forensic Science Ireland report shows purity levels of illicit drugs range from 9 to 35 per cent

Cocaine in Ireland has a purity level as low as 19 per cent and is usually mixed with veterinary medication for parasitic worms, a new study has shown.

Data published by Forensic Science Ireland on the purity of illicit drugs shows the average purity of street level cocaine in Dublin is 28 per cent, falling to 19 per cent outside the capital.

The average purity of amphetamine seized by gardaí in 2015 was 9.2 per cent while the average purity of street level heroin was 33 per cent in Dublin and 35 per cent in the rest of the country.

International comparisons from across Europe show that amphetamine seizures were typically of 9 -19 per cent purity, cocaine typically 33 - 50 per cent purity and heroin is typically 13 - 23 per cent purity.


Common adulterants found in cocaine were levamisole, benzocaine, lignocaine, caffeine, and phenacetin. Levamisole is a veterinary medication used to treat parasitic worm infections and makes cocaine more potent. It was found in 73 per cent of the samples analysed.

Benzocaine and lignocaine (also known as lidocaine) are local anesthetics commonly used by dentists. Phenacetin is a painkiller.

Common adulterants found in heroin were caffeine and paracetamol. The most common adulterant found in amphetamine is caffeine.

Dr Tom Hannigan, director of chemical sciences at FSI said the addition of levamisole to cocaine is a relatively recent development, probably within the last five years, and that it tends to be added during production in South America.

Forensic Science Ireland analyses illicit drugs seized by An Garda Síochána and the Customs Service and issues Certificates of Analysis for court purposes.

The organisation expects 8,000 seizures to be submitted for analysis this year. It said the principal drugs of abuse detected in 2015 were cannabis, heroin, cocaine, benzodiazepines and MDMA (ecstasy).

Forensic Science Ireland monitors the purity of the main illicit drugs in use in Ireland. FSI monitors the purity of “bulk seizures” of cocaine, heroin and amphetamine by quantifying samples from all seizures of these drugs in packs weighing in excess of 25 grams.

FSI also monitors the purity of “street level” cocaine and heroin by analysing a representative sample of seizures of less than 25 grams.