Dagga use is a phenomenon that most people are confronted with in everyday life. It is often freely available in schools, it is available in most neighbourhoods and if you ask around, you will find that most of your colleagues have experimented with it at some time or another.
Even clinicians and websites describe the wonderful medicinal properties of dagga, e.g. that it works wonderfully for arthritis and glaucoma.
Worldwide, and also in South Africa, there is a heavy ongoing debate whether the substance should be legalised. Pro-dagga candidates describe the substance as not physically addictive and therefore not harmful. It is also suggested that there are no lasting, harmful side effects. But is this the complete truth?
Some research points to definite physical addictive effects of dagga. These results also indicate the development of "tolerance" after long-term use of the substance. This means that more of the substance must be used per occasion to reach the same effect of euphoria than was previously the case. There are also signs of withdrawal symptoms when someone suddenly stops using it. These include irritability, restlessness, insomnia, anorexia (loss of appetite) and moderate nausea.
Furthermore, it is known that the psychological dependence that develops over the long run is as strong as the physical dependence on the substance, and that it brings about the same cravings.
Much research has also been done on the short-term, acute effects of dagga, in other words, the effect of the substance on brain functioning while still in the body. It has, for example, been shown that a person’s motor and decision-making abilities are affected under the influence of dagga and that he/she for example cannot drive as well.
Furthermore, the substance has an effect on a person’s attention and concentration ability, as well as short-term memory. The person will thus typically have difficulty concentrating on new information and the subsequent recall of it.
Very long half-life
For a long time it was suggested that these side effects disappear as soon as dagga is not in a person’s system anymore or has been "worked out". The reality, in actual fact, is that the substance has a very long "half-life". This means that it takes quite a while for the substance to have its effect and be eliminated from the body – up to 30 days.
The use of dagga in combination with methamphetamines (Tik) – which in the Western Cape is usually smoked in a crystal form, is very common. In this region, it is now the most widely used combination in young people under the age of 20. The effects of these drugs on the developing brain of young people have not been well-studied. Also the potential for long-term effects is there and also requires investigation.
Researchers at the Department of Psychiatry, University of Stellenbosch, are currently beginning studies in this area, using sophisticated brain scanning techniques as well as detailed tests of brain function.
Need more info?
Any person who has a query regarding the effects of dagga or methamphetamine (Tik) on brain functioning, or who is under 16years and using the substance, and would like to participate in a research study, please contact the Mental Health Information Centre on (021) 938 9229.
- Mental Health Information Centre, Department of Psychiatry, University of Stellenbosch
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