Cannabis or Marijuana use can worsen the effects of an Acquired or Traumatic brain injury and is connected to a wide range of cognitive and emotional issues, including memory and attention impairments and mental health issues.

• How Cannabis works
• Statistics
• Cannabis/Marijuana use after Acquired Brain Injury
• Mental Illness & Cannabis Use
• Treatment Approaches

How Cannabis works

People smoke cannabis for a number of reasons. Some of these include stress relief and to cope with difficult feelings, boredom or to gain acceptance within a social circle. Using cannabis can become a primary coping tool for difficult feelings. However the long term use of cannabis can prevent a person from learning new skills to effectively cope with day to day stressors and instead contribute to further problems in life. These problems include mental health issues, employment and relationship issues and for a person with a brain injury it can impact progress made through rehabilitation.

The active chemical in cannabis is THC (delta-9-tetrahydrocannabinol), which gives the ‘high’ feeling. To produce this effect, the chemical enters the blood stream, which carries it to the brain, producing changes in mood and perception [1]. Cannabis is a depressant, which means it, slows down the central nervous system causing a relaxed feeling throughout the body [2]. Cannabis is used interchangeably with the terms marijuana, pot and hash.

General effects include:

• Loss of co-ordination
• Low blood pressure and faintness
• Blurred vision
• Poor judgment
• Reduced attention
• Changes in Mood

Heavy use is associated with:

• Paranoia
• Anxiety
• Confusion
• Poor memory
• concentration

The effects of Cannabis are associated with a number of risks. Short term risks include injury due to falls, risks taking behaviors and car accidents. More long term risks include lung cancer, mental or psychotic illness and decline in productivity and problems with employment and relationships.

Statistics

• Of recent marijuana/cannabis users, 16.5% reported diagnosis and/or treatment for a mental health condition in the last 12 months, compared with 8.6% of non-users [4].
• A study exploring Cannabis related presentations in an emergency department in Sydney found physical health problems, such as gastrointestinal, neurological and cardio-respiratory problems were the most common presentations followed by mental health problems and injury [5].

Cannabis/Marijuana use after a Brain Injury

After acquired brain injury a person may become more sensitive to the effects of drugs including cannabis. After an acquired or traumatic brain injury it is recommended that cannabis be avoided. Some of the reasons, in addition to the above, include:

• Cannabis use following Acquired Brain Injury can magnify existing effects of a brain injury including poor memory and attention, impulsivity and poor muscle coordination, speech difficulties.
• Long-term use has lasting effects on memory and attention skills on top of damage already sustained through Acquired Brain Injury. These problems worsen the longer cannabis use continues.
• Cannabis use can interfere with recovery and participation in community programs following an Acquired Brain Injury.
• In a person with a brain injury cannabis use is more likely to produce adverse effects, including decline in memory, attention and confusion.
• Smoking Cannabis may temporarily relax a person; however when the effects of cannabis have warned off a person is likely to experience higher anxiety levels and panic. Studies have indicated that long-term, heavy cannabis use causes brain damage that is equivalent to mild-traumatic brain injury or premature ageing [6]. Certain studies have also shown that parts of the brain involved in memory and emotion were smaller in heavy users [7].

Mental illness & Cannabis Use

Cannabis use has been linked to mental illness including depression, anxiety and schizophrenia. However, the way the two are linked is not agreed upon. Some theories suggest that cannabis use causes mental illness in those with pre-existing mental illness and or exacerbates existing symptoms. However, cannabis is also known to induce schizophrenic like symptoms in otherwise healthy individuals. The effects of cannabis can be more harmful in the long term for those with an existing mental illness or predisposition to mental illness. The association between cannabis use and later experience of psychosis is stronger for those who start using Cannabis when young, use frequently and use heavily [8].

• If you have a family history of schizophrenia or other mental health conditions, cannabis should be avoided.
• If you have an existing mental illness, total abstinence is your best option.

Treatment Approaches to Cannabis Use

It is advisable that guidance be sought from a professional when giving up cannabis after an Acquired Brain Injury. This guidance may be sought through a drug rehabilitation service, a registered psychologist or counselor experienced in drug issues. It is advisable that the professional providing assistance has knowledge of acquired brain injury. Contact your Brain Injury Association for options in your area.

Treatment Approaches:

• Cognitive Behavioural Therapy (CBT) – This is an approach that aims to influence negative emotions, behaviors and thoughts. There are many therapeutic techniques under the title of Cognitive Behaviour Therapy, including keeping a diary of significant events and associated feelings, thoughts and behaviors, challenging unhelpful and unrealistic thoughts and testing assumptions and beliefs.
• Behavioural Therapy - Behavioural Therapy is an approach focusing on the modification of unhelpful behaviors. This involves a period of assessment of the behaviour looking at what influences the occurrence of a specific behaviour or its triggers, and what maintains the behaviour (its consequences). This assists in working out the best strategies to assist a person to modify or replace the undesirable behaviour with a more functional one.
• Motivational Interviewing – A type of counselling that aims to alter a person’s view of the costs and benefits of continued alcohol or drug use. This is done in a non-confronting way using counselling skills. The goal is to move a person toward a readiness to change.
• Medication (serious cannabis dependence) – medication use may be used to manage cravings and the side effects of withdrawal.

Self Management strategies:

• Admit that you have an issue with cannabis use
• Explore the consequences of drug use – both the positive short term rewards of use and negative short and long term risks and effects.
• Keep a diary on your drug use. Paying particular attention to triggers for use, this will help you to identify when coping techniques such as distraction, or breathing exercises need to be used if stress is a trigger for use.
• Become involved in a support group or community group for further support.

How Family Can Help:

• Provide ongoing support, stopping drugs is an ongoing process and a person may need your support more than ever as they go through the process of changing their habit. A person trying to quit may experience depression and increased anxiety.
• Support and encourage the use of new and helpful coping skills to resist cravings.
• Seek out support and advice for your self through a support group, information line or a counsellor.

Helpful Contacts

• Alcohol and Drug Information Service (ADIS): 1800 177 833
• National Cannabis Information and Helpline: 1800 30 40 50
• Alcohol and Drug Service, Brisbane Harm Reduction Centre (ADS) Ph. (07) 3238 4047
• Cannabis Use Self-Help Materials - http://www.justaskus.org.au/browse/drugs/cannabis-use-self-help-materials

References:

[1] Hall, W., L. Degenhardt, and M. Lynskey, The health and psychological effects of cannabis use. National Drug Strategy Monograph Series. Vol. 44. 2001, Canberra: Commonwealth Department of Health and Ageing.

[2] http://www.druginfo.adf.org.au/druginfo/drugs/drugfacts/cannabis.html

[3] Australian Institute of Health and Welfare, 2008 National Drug Strategy Household Survey: first results. Drug Statistics Series number 20. Cat. no. PHE 98, AIHW: Canberra.

[4] Australian Institute of Health and Welfare, 2004 National Drug Strategy Household Survey: Detailed findings. AIHW cat. no. PHE 66. 2005, AIHW: Canberra

[5] National Cannabis prevention and information centre 2008 “Population trends in cannabis use and first results of a study on cannabis-related emergency department presentations” (accessed 5 September 2008)

[6] http://www.abc.net.au/news/stories/2008/06/04/2264668.htm

[7] http://www.abc.net.au/worldtoday/content/2008/s2265148.htm

[8] Department of Health and Aging. (2008). Cannabis and Mental Health: Put in Context. National Drug Strategy, Monograph Series no. 68