Cannabinoids have been used for hundred of years for medical purposes. To day, the cannabinoid delta-9-tetrahydrocannabinol (THC) and the cannabis extract nabiximols are approved for the treatment of nausea, anorexia and spasticity, respectively. In Tourette syndrome (TS) several anecdotal reports p … CBD (cannabidiol) is believed to have antipsychotic properties(1) that may benefit individuals with mental health disorders, such as Tourette's syndrome (TS). Tic disorders are defined by the presence of motor and/or vocal tics. Motor tics are simple or more complex abrupt involuntary movements that can occur all over the body, but most often are located in the face and head. Vocal tics are characterized by meaningless "simple" sounds or noises, but also can be more "complex" including obscene words. Tourette syndrome (TS) is
Treatment of Tourette syndrome with cannabinoids
Cannabinoids have been used for hundred of years for medical purposes. To day, the cannabinoid delta-9-tetrahydrocannabinol (THC) and the cannabis extract nabiximols are approved for the treatment of nausea, anorexia and spasticity, respectively. In Tourette syndrome (TS) several anecdotal reports provided evidence that marijuana might be effective not only in the suppression of tics, but also in the treatment of associated behavioural problems. At the present time there are only two controlled trials available investigating the effect of THC in the treatment of TS. Using both self and examiner rating scales, in both studies a significant tic reduction could be observed after treatment with THC compared to placebo, without causing significant adverse effects. Available data about the effect of THC on obsessive-compulsive symptoms are inconsistent. According to a recent Cochrane review on the efficacy of cannabinoids in TS, definite conclusions cannot be drawn, because longer trials including a larger number of patients are missing. Notwithstanding this appraisal, by many experts THC is recommended for the treatment of TS in adult patients, when first line treatments failed to improve the tics. In treatment resistant adult patients, therefore, treatment with THC should be taken into consideration.
Müller-Vahl KR, Schneider U, Prevedel H, Theloe K, Kolbe H, Daldrup T, Emrich HM. Müller-Vahl KR, et al. J Clin Psychiatry. 2003 Apr;64(4):459-65. doi: 10.4088/jcp.v64n0417. J Clin Psychiatry. 2003. PMID: 12716250 Clinical Trial.
Müller-Vahl KR, Schneider U, Koblenz A, Jöbges M, Kolbe H, Daldrup T, Emrich HM. Müller-Vahl KR, et al. Pharmacopsychiatry. 2002 Mar;35(2):57-61. doi: 10.1055/s-2002-25028. Pharmacopsychiatry. 2002. PMID: 11951146 Clinical Trial.
Szejko N, Saramak K, Lombroso A, Müller-Vahl K. Szejko N, et al. Neurol Neurochir Pol. 2022;56(1):28-38. doi: 10.5603/PJNNS.a2021.0081. Epub 2021 Oct 28. Neurol Neurochir Pol. 2022. PMID: 34708399 Review.
Müller-Vahl KR, Prevedel H, Theloe K, Kolbe H, Emrich HM, Schneider U. Müller-Vahl KR, et al. Neuropsychopharmacology. 2003 Feb;28(2):384-8. doi: 10.1038/sj.npp.1300047. Neuropsychopharmacology. 2003. PMID: 12589392 Clinical Trial.
Curtis A, Clarke CE, Rickards HE. Curtis A, et al. Cochrane Database Syst Rev. 2009 Oct 7;2009(4):CD006565. doi: 10.1002/14651858.CD006565.pub2. Cochrane Database Syst Rev. 2009. PMID: 19821373 Free PMC article. Review.
Roessner V, Eichele H, Stern JS, Skov L, Rizzo R, Debes NM, Nagy P, Cavanna AE, Termine C, Ganos C, Münchau A, Szejko N, Cath D, Müller-Vahl KR, Verdellen C, Hartmann A, Rothenberger A, Hoekstra PJ, Plessen KJ. Roessner V, et al. Eur Child Adolesc Psychiatry. 2022 Mar;31(3):425-441. doi: 10.1007/s00787-021-01899-z. Epub 2021 Nov 10. Eur Child Adolesc Psychiatry. 2022. PMID: 34757514 Free PMC article. Review.
Fuentes-Verdugo E, López-Tolsa GE, Pellón R, Miguéns M. Fuentes-Verdugo E, et al. Psychopharmacology (Berl). 2022 May;239(5):1359-1372. doi: 10.1007/s00213-021-05952-2. Epub 2021 Aug 26. Psychopharmacology (Berl). 2022. PMID: 34436650 Free PMC article.
Nicolini H, Martínez-Magaña JJ, Genis-Mendoza AD, Villatoro Velázquez JA, Camarena B, Fleiz Bautista C, Bustos-Gamiño M, Aguilar García A, Lanzagorta N, Medina-Mora ME. Nicolini H, et al. Front Psychiatry. 2021 May 10;12:664228. doi: 10.3389/fpsyt.2021.664228. eCollection 2021. Front Psychiatry. 2021. PMID: 34040556 Free PMC article.
Kayser RR, Snorrason I, Haney M, Lee FS, Simpson HB. Kayser RR, et al. Cannabis Cannabinoid Res. 2019 Jun 14;4(2):77-87. doi: 10.1089/can.2018.0049. eCollection 2019. Cannabis Cannabinoid Res. 2019. PMID: 32656342 Free PMC article. Review.
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Best CBD Oil for Tourette’s Syndrome – August 2022
Why People Are Turning to CBD for Tourette’s Syndrome
Tourette’s syndrome (TS) is a mental disorder characterized by repetitive, involuntary movements and vocalizations known as tics. The motor tics represent a cardinal symptom traditionally linked to a dysfunction of the basal ganglia (4) .
Some examples of simple tics include eye blinking, facial grimacing, and head or shoulder jerking (5) .
The onset of TS usually occurs before the age of twenty-one, and its cause is relatively unknown (6) .
Cannabidiol ( CBD ) is believed to cause antipsychotic effects (7) , which may benefit people with mental illnesses, such as Tourette’s syndrome .
CBD is a chemical compound acquired from cannabis plants that have shown potential therapeutic applications in neuropsychiatric disorders (8) .
CBD is the opposite of tetrahydrocannabinol ( THC ), another cannabis constituent, in that it does not cause mind-altering effects upon use.
A study published by the journal Brain Sciences analyzed the effects of nabiximols, a combination drug containing THC and CBD , on a TS patient . The twenty-two-year-old male subject was given a daily dose of the medication for two weeks.
Researchers discovered that the treatment resulted in significant improvements of both tics and premonitory urges in the patient (9) .
They also noted that CBD ’s presence might have made the combination a more effective treatment , due to its ability to mitigate THC ‘s psychotropic effects.
These findings are similar to a 2016 study wherein a TS patient demonstrated marked improvement in movement and vocal tics after treatment with Sativex (10) , the trade name for nabiximols.
This study aimed to evaluate the efficacy of Sativex when applied to a treatment-resistant TS . The subject was given a daily dose containing 10.8 mg of THC and 10 mg of CBD for several weeks.
Based on subjective and objective measures, the Tourette’s syndrome patient displayed significant improvements in the frequency and severity of motor and vocal tics post-treatment (11) .
The study’s authors concluded that their results support the suggestion that cannabinoids, like CBD , may be used to treat Tourette’s syndrome .
Although the data on CBD for Tourette’s patients are minimal, these findings hint that the cannabis compound may be a potential therapeutic agent for the mental disorder.
How CBD Oil Works to Help with Tourette’s Syndrome
To understand how CBD may benefit people with Tourette’s syndrome , learning about its interaction with the endocannabinoid system (ECS) is essential.
The ECS is a part of the human body that researchers believe regulates a variety of crucial bodily functions. There is evidence implying that the endocannabinoid system is involved in the cause, symptomatology, and treatment of mental illnesses (12) .
The CB1 and CB2 cannabinoid receptors, the primary transmitters used by the ECS, are said to be involved in neurodegenerative disorders (13) .
This idea may stem from findings, particularly of CB1 receptors, which are found to be abundant in areas associated with movement and mental processes.
Cannabinoids, such as CBD , are believed to have neuroprotective properties based on their interaction with these ECS receptors (14) .
CBD is also reported to modulate various receptors outside the ECS. For instance, the compound is said to exert its neuroprotective effects based on how it engages with adenosine receptors (15) .
The compound is reported to increase adenosine levels in the brain. Increased adenosine has been linked to neuroprotection (16) .
The Pros and Cons of CBD Oil for Tourette’s Syndrome
- CBD may benefit individuals with Tourette’s syndrome . Early studies have shown that taking a dose mixed with cannabidiol improved motor and vocal tics in TS patients .
- People in the United States can purchase CBD in most places. In states where cannabidiol is allowed, users can buy CBD products even if they do not present a doctor’s prescription.
- CBD is a non-euphoric substance that does not cause a person to feel “high” after intake, unlike THC . CBD is also thought to counteract the psychoactive effects of tetrahydrocannabinol .
- The World Health Organization (WHO) published a report stating that they found CBD to be well-tolerated in humans. The subjects that they assessed from past clinical trials did not seem to develop substance dependence after CBD use (17) .
- CBD ‘s potential therapeutic applications have been acknowledged by the U.S. Food and Drug Administration ( FDA ) (18) . The FDA supports medical research concerning the use of cannabis and its derivatives.
- The United States 2018 Farm Bill legalized the cultivation of hemp and the sale of hemp-derived products, so long as the items are produced in a manner consistent with the law (19) .
- Human studies on CBD ‘s efficacy for Tourette’s syndrome have been carried out on individual patients. The lack of more in-depth studies has made it difficult for experts to determine if CBD can effectively treat the condition.
- Many CBD products sold today are prone to mislabeling (20) . Buying cannabidiol online and in some physical dispensaries puts people at risk of consuming more or less of the compound.
- A study in 2017 assessed the safety and potential adverse reactions of using CBD . Although considered safe, CBD can still interact with other prescription medications and cause harmful side effects to users (21) .
- Epidiolex, a drug used to treat two rare forms of epilepsy, is the only CBD product that has been approved by the FDA thus far (22) .
How CBD Oil Compares to Alternative Treatments for Tourette’s Syndrome
Hypnotherapy is considered an alternative treatment of Tourette syndrome for managing tics. The approach is meant to provide relaxation and concentration so that undesired thoughts are eliminated (23) .
Antidepressants have also been reported as treatment options that help control symptoms of anxiety and sadness.
For instance, a dose of imipramine (Tofranil) was found to improve depression and behavior in a patient with Gilles de la Tourette’s syndrome (GTS) (24) .
Similarly, cannabidiol is said to have properties that can reduce anxiety and promote relaxation.
One case report on a patient with post-traumatic stress disorder revealed that CBD improved the quality and quantity of the subject’s sleep. It was also found that CBD oil treatment resulted in a sustained decrease in anxiety (25) .
A clinical study published by The Permanente Journal analyzed evidence concerning CBD ‘s supposed effects in sleep and anxiety.
The researchers assessed seventy-two adult patients and learned that more than half of the subjects experienced improvements in anxiety and sleep scores (26) .
These findings suggest that CBD may be useful for people with Tourette’s syndrome .
How to Choose the Right CBD for Tourette’s Syndrome
Full-spectrum, broad-spectrum, and CBD isolates are the three types of CBD available today.
The full-spectrum CBD oil is considered to be the most popular among the three. It contains all of the naturally-occurring compounds of cannabis plants, such as flavonoids, terpenes, and THC .
Full-spectrum CBD products are high in cannabidiol and only contain small amounts of the other compounds.
Full-spectrum CBD is perhaps the most potent and effective form of CBD oil due to the cannabinoid synergism known as the “entourage effect (27) . ” This effect is a proposed mechanism wherein cannabis compounds are more effective when consumed together.
The second type of CBD is known as broad-spectrum. This variant is similar to full-spectrum, except that it does not contain tetrahydrocannabinol .
THC is a psychoactive compound that is often associated with medical marijuana . Some users prefer to use broad-spectrum CBD oil because of its lack of THC content.
The third option when buying cannabidiol products is CBD isolates. This CBD variant is often sold in powdered or crystalline form.
Users who want to take only pure CBD can purchase isolates. CBD products that only contain cannabidiol do not have a distinct taste or smell.
No matter the type of CBD one decides to purchase, it is essential to choose the best quality product all the time to maximize its supposed health benefits .
Below are additional tips that can help users select the best CBD oil for Tourette’s syndrome :
- Acquire a laboratory report or a certificate of analysis (COA) of the chosen CBD product . This document indicates that the item has undergone strict testing and contains the exact specifications listed on its label.
- Select and purchase only CBD derived from hemp. Industrial hemp is the most reliable source of obtaining top-quality cannabidiol .
- Make sure to read up on product and shop reviews before buying from an online CBD store. When purchasing from a physical dispensary, ensure that the establishment has the authorization to sell CBD products .
- Be aware of the legalities concerning the purchase and application of CBD in the state where one plans to consume it.
- Consult a healthcare professional, particularly someone with experience in using medical cannabis , before using any CBD product .
CBD Dosage for Tourette’s Syndrome
At the time of writing, the FDA has not approved any CBD product for treating patients with Tourette’s syndrome . Therefore, no official dosage guidelines are available.
However, studies on CBD showed that doses of 300 mg to 600 mg of CBD were able to reduce anxiety in human subjects (28) .
A single dose of 160 mg of CBD reportedly improved sleep duration in a crossover case study with nitrazepam, a medication for anxiety and insomnia (29) .
Meanwhile, doses reaching 1,500 mg of CBD per day have repeatedly shown to be well-tolerated in human participants (30) .
How to Take CBD Oil for Tourette’s Syndrome
Users who want to measure CBD hemp oil they take accurately may benefit from CBD tinctures. This delivery format allows a person to apply the cannabidiol oil sublingually.
CBD as tinctures come with droppers, making it easy to measure and apply the compound under the tongue.
For those looking to use CBD for relaxation, topicals are the most recommended choices. CBD in topical form is available as balms, creams, and salves and may be used in massage therapies.
Meanwhile, CBD is also sold as edibles or capsules. These products are the most straightforward way of taking cannabidiol and are great for those using CBD for the first time.
CBD gummies can be found in different shapes and sizes. The most common flavors are apple, blueberry, and watermelon.
Symptoms of Tourette’s Syndrome
Tics are the main symptoms of people with TS. These symptoms often show up when a child is between five to ten years of age.
Motor and vocal are the two types of tics.
Motor tics are the involuntary movements of the body, such as jerking an arm or shrugging the shoulders.
Vocal tics are the sounds that a patient makes with their voice. Some examples of vocal tics include humming, yelling, and throat clearing .
Typical initial symptoms of TS are motor tics that occur in the neck and head area. These tics usually become worse when the individual becomes stressed or excited but tend to improve when they are calm or focused.
In most cases, Tourette’s syndrome tics decrease once a person reaches adolescence and sometimes disappear entirely. However, many individuals with TS retain their tics in adulthood and, in some cases, become worse (31) .
Besides tic disorders , people with Tourette’s syndrome can also exhibit other symptoms.
They may have obsessive-compulsive disorder ( OCD ), attention deficit hyperactivity disorder (ADHD), or other significant learning difficulties (32) .
Excessive foul language and swearing ( coprolalia ) are rare and only affect about one out of ten people with Tourette’s syndrome .
Repeating sounds, words, or phrases ( echolalia ) is also another symptom of TS.
Tourette’s syndrome patients may also display behavioral problems, such as antisocial behavior, rage attacks, and inappropriate behavior.
Most people with TS experience a strong urge before a tic. Known as premonitory sensations, they are often relieved once the movement has been carried out.
Some examples of premonitory sensations include a burning feeling in the eyes before blinking, a dry or sore throat before grunting, and an itchy muscle before jerking.
The nervous system disorder known as Tourette’s syndrome is characterized by repetitive, involuntary motor and vocal tics . Some examples include facial grimacing, muscle spasms , head or shoulder jerking, and eye blinking.
CBD is believed to have antipsychotic properties that may be beneficial to people with neurological disorders , like Tourette’s syndrome .
Researchers in follow-up studies have found that a combination of CBD and THC was able to significantly improve both tics and premonitory urges in patients.
Cannabidiol is believed to interact with the endocannabinoid system through the CB1 and CB2 receptors. Studies have also shown that CBD engages with other receptors outside of the ECS.
Although the data on CBD Tourette’s syndrome is quite limited, these findings suggest that the medicinal cannabis compound may be used as a treatment for Tourette’s syndrome .
There are various types of CBD products sold today. One can purchase edibles, topicals, and tinctures, depending on their preference.
CBD use is legal in most states. The United States Farm Bill of 2018 allows the sale and transport of CBD products, provided t hey are made in a manner consistent with the law.
Interested individuals should seek advice from a doctor before using a CBD product for their condition.
Treatment of patients with tic disorders and Tourette syndrome with cannabis-based medication
Dr. Kirsten R. Müller-Vahl is a Professor of Psychiatry at the Department of Psychiatry, Socialpsychiatry and Psychotherapy at the Hannover Medical School (MHH), Germany. She is a specialist in both neurology and adult psychiatry. From 1997 to 2003 she was a grant holder of the German government (Dorothea-Erxleben-Stipendium) for scientific research related to Tourette syndrome (TS). During the last 20 years she has investigated more than 1500 patients with TS (children and adults) and is the head of the Tourette-Syndrome outpatient department (since 1995). From, 2012-2016 she was the vice president of the European Society of the study of Tourette syndrome (ESSTS). She was a German representative of the COST Action BM0905 (“European Network for the Study of Gilles de la Tourette Syndrome”). She is a full partner and a working group leader in the EU funded programmes “European Multicentre Tics in Children Studies” (EMTICS) and “TS-EUROTRAIN-Interdisciplinary training network for Tourette Syndrome”. She is a member of the Medical Advisory Board of the Tourette Association of America (TAA) and an author of the guidelines for the treatment of TS of both ESSTS and the American Academy of Neurology. Since 1998, she is a member and 2. Chairwoman of the Association for Cannabinoid Medicines (ACM). She was a founding member of the International Association for Cannabinoid Medicines (IACM) and from 2007-2009 1. Chairwoman and since 2015 vice president of the IACM.
Tic disorders are defined by the presence of motor and/or vocal tics. Motor tics are simple or more complex abrupt involuntary movements that can occur all over the body, but most often are located in the face and head. Vocal tics are characterized by meaningless “simple” sounds or noises, but also can be more “complex” including obscene words. Tourette syndrome (TS) is complex neurological-psychiatric disorder defined by the presence of both multiple motor and at least one vocal tic.
Tic disorders and Tourette syndrome
TS is a neurodevelopmental disorder and therefore age at onset is in childhood – most typically at age 6 to 8 years. The vast majority of patients with TS, however, suffer not only from motor and vocal tics, but also from one or more behavioral problems such as attention deficit/hyperactivity disorder (ADHD), obsessive-compulsive behavior (OCB), anxiety, depression, rage attacks, self-injurious behavior, sleeping disorder, but also leaning problems and autism spectrum disorder. Therefore, in many patients quality of life is substantially impaired.
Treatment of patients with tic disorders and Tourette syndrome
Due to the complex symptomatology and changes in clinical presentation over time, treatment of patients with TS is often challenging. Until today, tics cannot be cured. Established treatment strategies for tics include either behavioral therapy or pharmacotherapy with anti-psychotic drugs. While behavioral therapy does not cause adverse events, on average a tic improvement of only 30% can be achieved. Compared to behavioral therapy, pharmacotherapy with antipsychotics is more effective and often results in a tic reduction of about 50%. However not all patients benefit from antipsychotic medication and in many patients it is associated with relevant side effects such as sedation, weight gain, and sexual dysfunction. Patients, who suffer in addition from clinically relevant psychiatric disorders, need a combined treatment, since until today there is no therapeutic approach known that improves not only tics, but also psychiatric comorbidities. Therefore, many patients with TS are unsatisfied with available treatment strategies and seek for alternative medicine.
Against this background, new treatment strategies are urgently needed for this group of patients. Ideally, these new treatments (i) are associated with lesser side effects compared to available substances, (ii) result in a better improvement – or even a complete remission – of tics, (iii) are also effective in otherwise treatment resistant and severely affected patients, and (iv) improve not only tics, but the whole spectrum of the disease including different psychiatric symptoms such as ADHD, OCB, and depression.
Cannabis-based medication for patients with tic disorders and Tourette syndrome
In 1988, for the first time it has been suggested that cannabis might be such an alternative treatment option for patients suffering from TS. In this report, three male patients at ages 15, 17 and 39 years were described, who experienced a reduction in motor tics and premonitory urge sensations, an improvement in self-injurious behavior tendencies, attention, and hypersexual behavior as well as a generalized feeling of relaxation when smoking cannabis. No side effects occurred and treatment effect was stable over time and did not decrease. Since this initial report, a small number of case studies has been published describing beneficial effects of cannabis as well as other cannabis-based medications in patients with TS. There are no reports available about severe side effects or cannabis addiction. In most of these case studies, the authors report about beneficial effects on both tics and psychiatric symptoms. In many of the patients pharmacotherapy with other substances (such as antipsychotics for the treatment of tics, methylphenidate for the treatment of ADHD, or antidepressants for the treatment of depression, anxiety, and OCB) could be stopped.
Retrospective studies of cannabis
In 1998, in Germany a survey has been performed among patients with TS exploring the frequency and effect of (illegal) cannabis use. Of 64 patients, who were interviewed, 17 (27%) reported the use of cannabis and of these 14 (82%) reported that they felt cannabis improved their tics and premonitory urges as well as behavioral symptoms such as OCB and ADHD.
In line with this data, only recently researchers from Canada reported results from a retrospective evaluation on the effectiveness and tolerability of cannabis in 19 adults with TS. On average, they found a tic reduction of 60%, and 95% of patients were rated as at least “much improved.” In several patients, in addition, an improvement of psychiatric problems was reported. Cannabis was generally well tolerated and only mild side effects occurred such as decreased concentration, motivation and short-term memory, anxiety, increased appetite, sedation, and dry mouth and eyes.
In a retrospective study, we analyzed data from 98 patients with TS (mean age = 28.2 (+13.7) years) treated with different cannabis-based medications in our specialized Tourette outpatient clinic at Hannover Medical School, Hannover, Germany (unpublished data). Most of our patients used illegal cannabis (from different sources) (71%) for the treatment of TS. Only 37% of patients were treated with tetrahydrocannabinol (THC, dronabinol, the most psychoactive ingredient in cannabis), 32% received treatment with nabiximols (Sativex®, a cannabis extract standardized for THC and cannabidiol (CBD) at a 1:1 ratio), and 22% had access to (standardized) medicinal cannabis (from a pharmacy). The high percentage of illegal cannabis use – compared to the low percentage of treatments with medicinal cannabis – is related to the fact that in Germany only in March 2017 national laws changed and only since that time cannabis can be prescribed by medical doctors. Before March 2017, treatment with medical cannabis was restricted to a small group of patients, who have had received a specific permission by the German federal opium agency. However, when asking patients about the preferred kind of cannabis-based medication (if available), interestingly, 2/3 of patients answered that they would prefer inhaled medicinal cannabis (from a pharmacy) over other cannabis-based medications. In line with this preferred choice, medicinal cannabis was reported as more effective in reducing tics than other cannabis-based medications (in descending order): in 100% (N=21) of patients using medicinal cannabis, in 90% (=67) using illegal cannabis, in 77% (N=35) using THC (dronabinol), and in 76% (N=33) using nabiximols (Sativex®) (multiple answers possible). Accordingly, patients also assessed cannabis (both from illegal sources and medicinal cannabis from a pharmacy) more effective than nabiximols (Sativex®) and THC (dronabinol) in reducing psychiatric symptoms including OCB, ADHD, depression, anxiety disorders, self-injurious behavior, rage attacks, and sleeping problems. Altogether, patients assessed cannabis superior compared to both nabiximols (Sativex®) and THC (dronabinol).
Placebo-controlled trials using THC
Currently, only two preliminary controlled trials have been conducted to investigate the efficacy and safety of orally administered THC (dronabinol) in patients with TS. In a pilot study, a single dose of THC was compared to placebo in a crossover study of 12 adults. In a follow-up study, efficacy and tolerability of THC was compared to placebo in a 6 week trial of 24 adults. In both studies, treatment with THC resulted in a significant improvement of tics. No severe side effects occurred, but transient mild adverse events such as dizziness and tiredness.
Side effects profile of cannabis-based medication
Interestingly, there is some evidence that tolerability and side effects profile of cannabis and cannabis-based medication may be different in patients with TS compared to healthy people. In parallel to the above mentioned controlled trials, neuropsychological performance and cognitive function have been investigated before, during and after treatment with THC (dronabinol). In these studies, no detrimental effects of THC were seen on any of assessments used. Measuring immediate verbal memory span, there was even a trend towards an improvement during treatment with THC (dronabinol). Completely in line with these findings, in a single case study, treatment of a 42 year old patient with TS with THC resulted not only in a 75% tic reduction, but also in an improvement of his driving ability as measured by standardized driving tests.
Summary and perspective
Based on these results from clinical reports and preliminary controlled studies, it has been suggested that cannabis-based medication may be a new and promising treatment strategy for patients with TS. However, it has also been speculated that TS might be caused by a dysfunction in the endocannabinoid system in the brain. This hypothesis fits perfectly with the clinical observation that treatment with cannabis-based medication results in an improvement of both tics and behavioral problems without causing clinically relevant impairment on concentration and psychomotor functions. Since it is well-known that the endocannabinoid system modulates several other neurotransmitter systems in the brain (including the dopaminergic, GABAergic, serotonergic and glutaminergic systems), a dysfunction in the central endocannabinoid system will result in imbalances in several other transmitter system and, thus, may explain the complex clinical symptomatology in TS.
Motivated by these promising data, several clinical studies have been initiated to further investigate the efficacy and tolerability of different cannabis-based medications in the treatment of patients with TS including nabiximols (Sativex®), THC (dronabinol) , and medicinal cannabis. In addition, pilot studies have already been initiated or are in preparation investigating the effects of cannabinoid modulators as well as the so called “entourage effect” in this group of patients. The entourage effect can be achieved by substances that enhance the action of endogenous cannabinoids such as anandamide. These studies are funded by either pharmaceutical companies or the German Research Society (DFG). Thus, our knowledge about the effects of cannabis-based medicine in patients with TS will definitely increase within the next few years. This is important and will be very helpful for patients with TS, because until today – at least in Germany and many other European countries – many doctors hesitate to prescribe medicinal cannabis, health insurances often refuse to cover the costs for this kind of treatment, and patients are often stigmatized as recreational cannabis users and cannabis-addicted, instead of being generally accepted as patients simply using that medication that is most effective for the treatment of their symptoms.