Overview of Anxiety Disorders
Anxiety disorders are a collection of mental disorders that cause such severe levels of distress and fear that they interfere with the ability to maintain daily life. There are several recognized types of anxiety disorders, including panic disorder, social anxiety disorder, specific phobias, and generalized anxiety disorder. The anxiety associated with anxiety disorders lasts for at least six months.
Panic disorders cause terror sensations that strike suddenly and without warning. Social anxiety disorder, or social phobia, causes feelings of overwhelming worry and self-consciousness about everyday social situations. Specific phobias cause an intense fear of a specific situation or object. Generalized anxiety disorder causes excessive and unrealistic worry and tension over minimal or non-threatening situations.
In addition to feelings of panic, fear and uneasiness, anxiety disorders can cause sleeping problems, cold or sweaty hands and feet, breath shortness, heart palpitations, dry mouth, an inability to be still and calm, numbness in the hands and feet, nausea, muscle tension and dizziness.
The cause of anxiety disorders is not yet known, but according to WebMD, research suggests that they stem from a combination of factors, including environmental stress and changes in the brain. Anxiety disorders commonly arise in association with other mental or physical illnesses, such as alcohol or substance abuse.
Treatment efforts for anxiety disorders can include working with a mental health professional and medications to reduce symptoms. Other coexisting conditions, like alcoholism or substance abuse, may need to be treated and addressed prior to anxiety disorder treatment.
Findings: Effects of Cannabis on Anxiety Disorders
Studies have shown that a major cannabinoid found in cannabis, cannabidiol (CBD), has been found to have an anxiolytic-like effect in both animal and human trials (Schier, et al., 2012) (de Mello, et al., 2014) (Sarris, McIntyre & Camfield, 2013). One study found that CBD significantly reduced anxiety, cognitive impairment and discomfort in social phobia patients before they were subjected to simulated public speaking (Bergamaschi, et al., 2011). A similar study also discovered that CBD had an anxiolytic effect on individuals submitted to a simulated public speaking test (Zuardi, Cosme, Graeff & Guimaraes, 1993). Another found that CBD significantly decreased subjective anxiety in individuals diagnosed with social anxiety disorder (Crippa, et al., 2011).
Cannabinoids have shown they can reverse stress-induced anxiety by inhibiting fatty acid amide hydrolase, the anandamide-degrading enzyme (Bluett, et al., 2014). This is likely due to cannabinoid’s activation of the CB1 cannabinoid receptors, as activating these receptors have shown to inhibit the fatty acid amid hydrolase and subsequently reduce anxiety (Moreira, Kaiser, Monory & Lutz, 2008). One study found that it was through CBD’s activation of the cannabinoid receptors that provided an anxiolytic effect in stressed mice (Campos, et al., 2013). Another study, however, showed that it was through CBD’s activation of 5-HT1A receptors that caused an anxiolytic-like effect in rats exposed to tests (Gomes, Resstel & Guimaraes, 2011). In another, CBD’s action on limbic and paralimbic brain areas were shown to be responsible for its anxiolytic properties in (Crippa, J.A., et al., 2004).
References
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Anxiety & Panic Disorders Health Center: Anxiety Disorders. (n.d.). WebMD. Retrieved from http://www.webmd.com/anxiety-panic/guide/mental-health-anxiety-disorders.
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Anxiety Disorders. (2015, May). National Institute of Mental Health. Retrieved from http://www.nimh.nih.gov/health/topics/anxiety-disorders/index.shtml.
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Bergamaschi, M. M., Queiroz, R. H. C., Chagas, M. H. N., de Oliveira, D. C. G., De Martinis, B. S., Kapczinski, F., Quevedo, J., Roesler, R., Schroeder, N., Nardi, A.E., Martin-Santos, R., Hallak, J.E., Zuardi, A.W., and Crippa, J. A. S. (2011). Cannabidiol Reduces the Anxiety Induced by Simulated Public Speaking in Treatment-Naïve Social Phobia Patients. Neuropsychopharmacology, 36(6), 1219–1226.
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Bluett, R. J., Gamble-George, J. C., Hermanson, D. J., Hartley, N. D., Marnett, L. J., & Patel, S. (2014). Central anandamide deficiency predicts stress-induced anxiety: behavioral reversal through endocannabinoid augmentation. Translational Psychiatry, 4(7), e408.
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Campos, A.C., Ortega, Z., Palazuelos, J., Fogaca, M.V., Aguiar, D.C., Diaz-Alonso, J., Ortega-Gutierrez, S., Vazquez-Villa, H., Moreira, F.A., Guzman, M., Galve-Roperh, I., and Guimaraes, F.S. (2013, July). The anxiolytic effect of cannabidiol on chronically stressed mice depends on hippocampal neurogenesis: involvement of the endocannabinoid system. International Journal of Neuropsychopharmacology, 16(6), 1407-19.
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Crippa, J.A., Derenusson, G.N., Ferrari, T.B., Wichert-Ana, L., Duran, F.L., Martin-Santos, R., Simoes, M.V., Bhattacharyya, S., Fusar-Poli, P., Atakan, Z., Santos Filho, A., Freitas-Ferrari, M.C., McGuire, P.K., Zuardi, A.W., Busatto, G.R., and Hallak, J.E. (2011, January). Neural basis of anxiolytic effects of cannabidiol (CBD) in generalized social anxiety disorder: a preliminary report. Journal of Psychopharmacology, 25(1), 121-30.
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Crippa, J.A., Zuardi, A.W., Garrido, G.E., Wichert-Ana, L., Guarieri, R., Ferrari, L., Azevedo-Marques, P.M., Hallak, J.E., McGuire, P.K., and Filho Busatto, G. (2004, February). Effects of cannabidiol (CBD) on regional cerebral blood flow. Neuropsychopharmacology, 29(2), 417-26.
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de Mello Schier, A.R., de Oliveira Ribeiro, N.P., Coutinho, D.S., Machado, S., Arias-Carrion, O., Crippa, J.A., Zuardi, A.W., Nardi, A.E., and Silva, A.C. (2014). Antidepressant-like and anxiolytic-like effects of cannabidiol: a chemical compound of Cannabis sativa. CNS & Neurological Disorders Drug Targets, 13(6), 953-60.
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Gomes, F.V., Resstel, L.B., and Guimaraes, F.S. (2011, February). The anxiolytic-like effects of cannabidiol injected into the bed nucleus of the stria terminalis are mediated by 5-HT1A receptors. Psychopharmacology, 213(2-3), 465-73.
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Moreira, F.A., Kaiser, N., Monory, K., and Lutz, B., (2008, January). Reduced anxiety-like behaviour induced by genetic and pharmacological inhibition of the endocannabinoid-degrading enzyme fatty acid amide hydrolase (FAAH) is mediated by CB1 receptors. Neuropharmacology, 54(1), 141-50.
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Sarris, J., McIntyre, E., and Camfield, D.A. (2013, April). Plant-based medicines for anxiety disorders, part 2: a review of clinical studies with supporting preclinical evidence. CNS Drugs, 27(4), 301-19.
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Schier, A.R., Ribeiro, N.P., Silva, A.C., Hallak, J.E., Crippa, J.A., Nardi, A.E., and Zuardi, A.W. (2012, June). Cannabidiol, a Cannabis sativa constituent, as an anxiolytic drug. Revista Brasileiria de Psiquiatria, 34 suppl 1: S104-10.
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Zuardi, A.W., Cosme, R.A, Graeff, F.G., and Guimaraes, F.S. (1993, January). Effects of ipsapirone and cannabidiol on human experimental anxiety, Journal of Psychopharmacology, 7(1 Suppl), 82-8.