General remarks
The level of knowledge in the different areas of medical use of cannabis and cannabinoids is very heterogeneous. There is strong evidence of its therapeutic efficacy in the treatment of nausea and vomiting related to chemotherapy against cancer, anorexia and cachexia due to HIV / AIDS infection, long-term and especially neuropathic pain, spasticity in multiple sclerosis and spinal cord injury. With respect to other indications like epilepsy, itching and depression, there is much less information available. Scientific discoveries for a certain indication, however, do not reflect the actual therapeutic potential for a given disease.
Clinical studies on some cannabinoids or whole plant preparations (smoked cannabis, cannabis extract) have often been suggested by the positive experiences of patients using natural cannabis products. Thus, anti-emetic, appetite-stimulating, muscle-relaxing and analgesic effects, as well as therapeutic administration, have been discovered in the treatment of Tourette’s syndrome.
Accidental observations have also revealed useful therapeutic effects. This is the case in a study in patients with Alzheimer’s disease, where the stimulating effect of THC appetite was examined. Not only increased appetite and weight gain, but also decreased behavioral disturbance in patients. The discovery of the effect of THC administration on the decline in eye pressure in the early 1970s was equally brilliant and fortuitous. Other indications that may be of interest but have not yet been verified by medical research, and which remain routine problems of modern medicine, could be treated with cannabis or cannabinoids. It is for this reason that surveys of people who use therapeutic cannabis. These investigations took place either in the form of non-standardized interviews during research by governmental or scientific institutions (Science Committee of the House of Lords of Britain, United States Institute of Medicine) on the therapeutic potential of cannabis, either under form of anonymous surveys with standardized questionnaires.
Nausea and vomiting
The treatment of side effects associated with cancer therapies is the most studied application of cannabinoids to date with approximately 40 studies (THC, nabilone, other THC analogues, cannabis), most of which were conducted in the 1980s. In the cases studied, relatively high doses of THC were needed, and the resulting side effects appeared frequently. THC was less effective than high-dose metoclopramide in one study. There is no comparison between the effects of THC and recent serotonin antagonists. Recent clinical investigations have shown that the use of THC at low doses enhances the effectiveness of other antiemetic drugs taken simultaneously. Studies also show the effectiveness of cannabinoids on nausea and vomiting caused by radiotherapy and surgeries. In traditional medicine cannabinoids are often used and are often used for other causes of nausea including AIDS, hepatitis and pregnancy nausea.
Anorexia and cachexia
The stimulating effect of THC appetite is observed from doses of 5 mg daily THC. The dosage can be increased up to 20 mg per day if necessary. In a long-term study of 94 AIDS patients, the stimulating effect of THC appetite was maintained for several months, confirming the appetite stimulation seen in another patient. six-week study. Compared to placebo, THC doubled appetite measured on a similar visual scale. Instead, patients maintained a stable weight for seven months. A positive effect on weight has been reported in 15 patients with Alzheimer’s disease who previously refused to eat. In addition, cannabis products can improve appetite in patients with cancer or Chronic Obstructive Pulmonary Disease (COPD).
Spasms
For many clinical trials with THC, nabilone and cannabis, a good influence on spasticity caused by multiple sclerosis and spinal cord injury has been observed. Positively influenced symptoms include pain, paraesthesia, tremor, and ataxia. Some studies have shown an improvement in vesicular control. There are also anecdotal observations of the good influence of cannabis on spasms due to brain damage.
Gilles de la Tourette syndrome and other movement disorders
There are positive experiences in the treatment of Tourette’s syndrome, dystonia and tardive dyskinesia with cannabis. The use in Tourette’s syndrome is currently being studied in clinical studies. Most patients have a slight improvement, some of them, however, have a remarkable improvement, or even a complete symptom control. In some patients with multiple sclerosis, anti-ataxic effects have been observed after THC administration, as well as a decrease in tremor. Despite some positive reports, the beneficial effects were not observed in the case of Parkinson’s disease and Huntington’s chorea. However, cannabis products could possibly be used against dyskinesia triggered by L-Dopa in Parkinson’s disease, without aggravating the basic symptoms.
Pains
Significant clinical studies have demonstrated the analgesic properties of cannabis products. Possible indications include neuropathic pain in multiple sclerosis, brachial plexus involvement, AIDS infections, rheumatoid arthritis pain, cancer pain, headache, menstrual pain, chronic inflammations of the intestine such as ulcerative colitis or Crohn’s disease, and various neuralgias. It is possible to associate cannabinoids with opioids.
Pruritus
According to a short clinical study, cannabinoids, taken internally or externally as an ointment, improve the symptoms of pruritus due to various causes such as severe pruritus that appears in the case of liver diseases.
Glaucoma
In 1971, during a systematic survey of the effects of cannabis among healthy cannabis users, cannabis was found to reduce eye pressure. In the next 12 years, several studies on cannabis and several natural and synthetic cannabinoids were conducted in healthy subjects and patients with glaucoma. Cannabis reduces eye pressure by 25 to 30% on average, sometimes up to 50%. Some non-psychotropic cannabinoids and, to a lesser extent, some non-cannabinoid components of hemp also reduce eye pressure.
Epilepsy
The use in the treatment of epilepsy is among the oldest indications of cannabis. Studies in animals have demonstrated the anti-epileptic effect of some cannabinoids. The anti-epileptic effects of phenytoin and diazepam have been potentiated by THC. According to some 20th century reports, some patients with epilepsy continue to use cannabis as the only way to control seizures that are otherwise unmanageable. Cannabis can sometimes precipitate convulsions.
Asthma
Studies examining the anti-asthmatic effect of THC or cannabis are mostly from the 1970s and are exclusively acute studies. The effects of a cannabis cigarette (2% THC) or a dose of THC (15 mg) orally are approximately equivalent to the effects of clinical doses of common bronchodilator drugs (Salbutamol, Isoprenalin). Since the inhalation of cannabis products can irritate the mucous membranes, it is preferable that the consumption is done orally or by another alternative system. Very few patients have developed bronchoconstriction after inhalation of THC.
Dependency and craving
According to historical and modern reports, cannabis is an appropriate means of combating cravings in benzodiazepine, opioid and alcohol dependence. It is for this reason that some call it drug of abandonment. In this context, not only the decrease in the physical symptoms of withdrawal, but also the reduction in the stress associated with dropping out of narcotics could play a role in the observed positive effects.
Psychiatric symptoms
In several clinical studies with THC, mood enhancement has been observed in cases of reactive depression. There are other case reports that indicate positive effects of cannabinoids in the treatment of other diseases or psychiatric symptoms such as sleep disorders, anxiety, bipolar disorder, schizophrenic psychoses and depressive states (dysthymia). . According to several case reports, THC has been effective in treating severe refractory cases of compulsive disorder (OCD). Cannabinoids can also reduce the symptoms of post-traumatic stress disorder (PTSD). Different authors have formulated different points of view concerning psychiatric syndromes and cannabis. While some put more emphasis on the problems caused by cannabis, others emphasize the therapeutic possibilities. It is possible that cannabis products can be both beneficial and harmful.
Attention Deficit / Hyperactivity Disorder (ADHD)
Cannabis may, in some cases, be beneficial for people with Attention Deficit Disorder with or without Hyperactivity (ADHD – ADD).
Alzheimer’s disease
Clinical studies have shown that cannabis can not only improve the appetite of patients with Alzheimer’s disease, but also reduce disturbed behavior and agitation.
Autoimmune diseases, inflammation and allergies
For a number of painful and inflammatory syndromes (eg ulcerative colitis, arthritis) cannabis products are not only analgesic, but also demonstrate an anti-inflammatory potential. For example, some patients who use cannabis report a decrease in their need for steroidal and non-steroidal anti-inflammatory drugs. In addition, there are reports on the positive effects of self-medication with cannabis in case of allergy. It is not yet known whether cannabis-based products may have effects related to the processes responsible for certain autoimmune diseases.
Various, various syndromes
There are many positive testimonials from patients relating to medical conditions that are difficult to classify in the categories mentioned above; for example, hiccups, high blood pressure, tinnitus, chronic fatigue syndrome, Huntington’s disease, Parkinson’s disease, restless legs syndrome and others. Hundreds of possible indications have been described by different authors. An example is the success of treatment of chronic hiccups after surgery. No drug was effective except smoking a cannabis cigarette that completely wiped out the hiccups.
Cannabis products often show very good results in the treatment of multi-symptomatic diseases that correspond to the diversity of the effects of THC, for example against inflammatory pain (eg arthritis), or accompanied by an increase in muscle tone (eg painful periods, spinal cord injuries), or for diseases that are accompanied by nausea and anorexia in combination with pain, anxiety, or depression (eg, AIDS, cancer, hepatitis C).