Cannabinoids and Anorexia / Cachexia
Anorexia is defined as a person’s loss of appetite and weight; while Cachexia refers to a state of extreme malnutrition and loss of muscle mass that is accompanied by fatigue and weakness. These symptoms often appear in autoimmune diseases, infections and especially in people who have cancer because weight loss can occur as a symptom in more advanced stages of this disease. In fact, anorexia is the most common cause of weight loss in young women and the most common reason that children and adolescents are admitted to hospital .
Cachexia is manifested by a significant loss of weight from a decrease in muscle mass. The symptoms that we can observe are anorexia, asthenia, nausea, fatigue, general malaise and a very significant decrease in intake. In patients with cancer, their incidence varies depending on the type of tumour. .
In the case of AIDS, many patients suffer from cachexia along with other symptoms such as lack of appetite, anxiety, depression, mood swings, among others. Several clinical studies have shown the beneficial effects that medicinal cannabis can have on HIV-positive people, improving the symptoms of the disease and the side effects of antiretroviral treatment.
Cannabinoids can attenuate pain, increase intake by improving symptoms that come from cachexia (fatigue, weakness, asthenia, malaise), and alleviate nausea and vomiting caused by treatment in patients with HIV. Social pressure, rejection, or side effects produced by drugs used in antiretroviral therapy often result in depression, anxiety, and mood swings.
Cannabinoids have many properties that could benefit patients who have a loss of appetite and it can also improve their quality of life.
The endocannabinoid system and the regulation of appetite
The endocannabinoid system is involved in the regulation of appetite and seems to play an important role in diet and in disorders such as anorexia nervosa , . Endocannabinoids such as anandamide are known to act through the CB1 receptors of the brain, stimulating appetite and increasing food intake , . The disturbance of endocannabinoid signals can contribute to the development of eating disorders.
Effects of cannabinoids
Several studies have shown that the use of cannabinoids in people with anorexia or cachexia causes a significant increase in appetite, contributing to weight gain. People with pathologies in which the lack of appetite and malnutrition are a symptom (autoimmune, infectious diseases, cancer patients, among others) can benefit from the use of cannabinoids, with the advantage that they have few side effects and low toxicity.
Treatment of Anorexia and Cachexia with cannabinoids
Regarding the effects of medicinal cannabis to treat these diseases, clinical trials have demonstrated the efficacy of endocannabinoids at improving the lack of appetite and weight gain.
An open pilot study, conducted by Pharmacology Biochemistry and Behaviour, found that “the oral administration of THC, for five months, helped to increase the weight of 7 out of 10 patients with HIV, helping to improve their appetite”. 
On the other hand, the International Journal of Geriatric Psychiatry published a placebo trial performed on 15 patients diagnosed with Alzheimer’s who did not eat food because of lack of appetite. The study determined that THC is suitable for the treatment of anorexia and, in addition, improved symptoms of Alzheimer’s disease. The study also showed that patients who took cannabinoids significantly increased in weight compared to those who were given the placebo. 
Finally, the Journal Of Palliative Care, in its study “A phase II study of delta-9-tetrahydrocannabinol for appetite stimulation in cancer-associated anorexia”, determined that the use of THC to stimulate the hunger is effective, especially for patients in the advanced stages of cancer and whose life expectancy was not more than four weeks. “It was well tolerated at a low dose, but more studies are needed to determine the most appropriate dosage for the specific population” .
Bibliography for the treatment of Anorexia and Cachexia with cannabinoids
 D. Cardona(2006). Tratamiento farmacológico de la anorexia – caquexia cancerosa. Nutr. Hosp. vol.21 supl.3 Madrid may. 2006
 Matias I1, Bisogno T, Di Marzo V.Endogenous cannabinoids in the brain and peripheral tissues: regulation of their levels and control of food intake. 2006 Apr;30 Suppl 1:S7-S12.
 Monteleone P1, Matias I, Martiadis V, De Petrocellis L, Maj M, Di Marzo V.. Blood levels of the endocannabinoid anandamide are increased in anorexia nervosa and in binge-eating disorder, but not in bulimia nervosa.. Neuropsychopharmacology. 2005 Jun;30(6):1216-21.
 Aaron NA Verty,1, Megan J Evetts,1 Geraldine J Crouch,1 Iain S McGregor,2 Aneta Stefanidis,1 and Brian J Oldfield1. The Cannabinoid Receptor Agonist THC Attenuates Weight Loss in a Rodent Model of Activity-Based Anorexia. Neuropsychopharmacology. 2011 Jun; 36(7): 1349–1358.
 Kirkham TC1. Endocannabinoids in the regulation of appetite and body weight. Behav Pharmacol. 2005 Sep;16(5-6):297-313
 Volicer L, Stelly M, Morris J, McLaughlin J, Volicer BJ Effects of dronabinol on anorexia and disturbed behavior in patients with Alzheimer’s disease. International Journal of Geriatric Psychiatry 1997;12(9):913-919
 Nelson, K., Walsh, D., Deeter, P., & Sheehan, F. (1994). A phase II study of delta-9-tetrahydrocannabinol for appetite stimulation in cancer-associated anorexia Journal of Palliative Care, 10(1), 14-18.
Use cannabinoids for
Anorexia / Cachexia