Post Traumatic Stress Disorder (PTSD) is classified as a severe anxiety disorder which develops after exposure to terrifying, potentially life-threatening stimuli. The majority of the population recognises PTSD as a disorder affecting returning war veterans. While this is true, PTSD has also been shown to occur in police/fire services as well as in survivors of abuse, accidents, natural disasters and disease.
PTSD can affect people of any age, including young children. Beyond Blue states that “Around 1 million Australians experience PTSD in any one year, and 12 per cent of Australians will experience PTSD in their lifetime. Serious accidents are one of the leading causes of PTSD in Australia.”
The endocannabinoid system has been implicated in many scientific studies as a mediator of anxiety, depression as well as sleep through its interaction the neurotransmitter serotonin.
Treatment of PTSD Using Medical Cannabis
Serotonin is an essential neurotransmitter involved in the regulation of mood, sleep, appetite and libido. In the central nervous system serotonin communicates with numerous receptors responsible for a variety of biological functions.
The precise mechanism by which the endocannabinoid system modulates anxiety and depression is not fully understood. CBD is postulated to act as an agonist to the 5HT1A receptor. Activation of the 5HT1A receptor is understood to modulate the release of serotonin in the brain. In a study in which mice were pretreated with a 5HT1A antagonist, the antidepressant effects of CBD were absent, confirming the hypothesis. Further evidence of the role of 5HT1A is given by the observed similarities of CBD and isapirone (a 5HT1A partial agonist) in a public speaking model. The procedure of the simulated public speaking model consists of subjects speaking in front of a video camera during which time physiological indicators of anxiety (heart rate, blood pressure and skin conductance) are measured. Patients are then asked to subjectively quantify their feelings of stress and anxiety.
Impairment of hippocampal neurogenesis has been associated with the pathogenesis of anxiety disorders and depression. CBD is thought to stimulate hippocampal neurogenesis, a property absent in CB1 knockout mice. Researchers postulate that the mechanism is CB1 dependent. CBD is thought to reduce the efficiency of FAAH and reduce anandamide reuptake; hence the CB1 receptor is activated.
Medication is typically prescribed for the treatment anxiety and depression. Studies indicate that the SSRI’s and tricyclic antidepressants are very effective treatments for depression and anxiety. For extreme circumstances where the patient is experiencing panic and high levels of anxiety, benzodiazepines may also be prescribed. It typically takes about three weeks for most antidepressants to take effect. It is suggested that alongside medication, patients receive therapy to talk out their issues with a professional. Cognitive behaviour therapy (CBT) and Interpersonal psychotherapy (IPT) works best for the treatment of anxiety and depression. Both SSRI’s and benzodiazepines have significant side effects while clinical studies suggest that CBD produces little to no adverse effects in the short or long term.
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