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North Inner City Drugs Task Force


High Strength Cannabis: NICDTF Information Session

On the 16th of October 2012, NICDTF held an information seminar on high strength cannabis in response to local concern about serious health and wellbeing issues associated with the drug.


Dr. Des Corrigan - former chairman of the National Advisory Committee on Drugs

Gemma Collins – Co-ordinator of Crinan Youth Project

Ger O’Rourke – Assistant Director at the SAOL Project.

What’s different about cannabis now?

Much of the cannabis available in Ireland is now coming from indoor grow-houses / factories or sometimes from homegrown sources. This cannabis is sold as herb (dried leaves/buds) and is generally known as “Skunk” or “Weed”.

The indoor growing process combined with the selection of higher-strength plants has resulted in a much more potent drug than previously available, and there are greater negative effects on users.

What are the negative effects of high-strength cannabis (Skunk / Weed)?

In an NICDTF survey of local drugs services conducted in April 2012, project workers were asked which drugs were causing the greatest issues for clients. High-strength cannabis was identified as the substance causing the second greatest issue, that is, the same level of issue as heroin and cocaine.

View Summary of Survey

During the seminar, local project workers described how they have experienced a noticeable increase in the number of individuals presenting because their cannabis use has become a problem. Some of the issues they are experiencing include anxiety, depression, extreme paranoia, suicidal thoughts and loss of short-term memory. Many users (including teenagers) are getting into debt, which in turn is leading to intimidation issues, causing further stress and anxiety for whole families.

Dr. Des Corrigan gave a presentation on “Skunk and Weed” and illustrated the reasons why cannabis in Ireland is now more potent than before. He outlined the higher risks of Skunk and Weed compared to cannabis from a few years ago, and explained the short and long term effects of the drug. He particularly warned of the increased risks to young people, because of the way it interferes with the development of the adolescent brain.

Download “Skunk and Weed” Presentation (PDF 1.6MB)

Why are there greater negative effects with Skunk / Weed?

In brief, of the 500 or so chemicals to be found in cannabis, the most relevant are:

Tetrahydrocannabinol (THC)– Euphoriant/ Psychotogenic
Cannabidiol (CBD)– Anti-Anxiety/Anti-psychotic

The ratio of THC to CBD influences the effect of the drug:

Cannabis plants cultivated in grow-houses using hydroponic systems and intense lighting have far higher concentrations of the chemical THC. THC gives rise to the euphoric reaction and it also gives rise to the negative effects such as paranoia.

The anti-psychotic chemical CBD in cannabis seems to protect the brain from the effects of THC. Skunk and Weed are missing CBD.

Imported hash (resin) used to be the main form of cannabis in Ireland, while herb cannabis in Ireland used to be the weakest form of the drug. Hash would have contained equal amounts of THC and CBD. Recent samples from cannabis seizures in Ireland were found to have had between 4 -16% THC present, traditionally this would have been in the region of 1%.

The huge increase in THC levels combined with a lack of CBD in the plant is making Skunk and Weed a very different drug to the hash and herb cannabis traditionally available in Ireland. There is a need for the perception of cannabis and the risks associated with it to change in tandem with how the drug is evolving.

“Reduce the Use 2”

Ger O’Rourke of the SAOL Project presented information about “Reduce the Use 2” a 10 module course which was designed for groups of clients who wish to reduce or stop their drug use. It is based on the principles of cognitive behavioural therapy (CBT) and can be adapted to focus on any drug, including cannabis.

The “Reduce the Use 2” Manual is free and available on SAOL’s website:

News / Media:

The herb that got too high: Jan 7, 2012 

Teens and Marijuana: September 1, 2012 

Cannabis found to lower IQ of young: August 28, 2012

Concern over surge in cannabis cultivation: Jan 20, 2011