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  Medical Marijuana:

Reducing Spasticity in

Multiple Sclerosis Patients


Heather Post

What is Multiple Sclerosis?

Multiple Sclerosis (MS) is a chronic inflammatory disease of the central nervous system. MS affects approximately 3.0 million people globally, with about 300,000 cases in the United States. Twice as many women as men have MS. The average ages for onset of MS is 20-40 years. In MS, cells in the immune system attack and destroy myelin, the fatty tissue surrounding nerve cells ( Scar tissue replaces the myelin, interfering with the transmission of nerve signals and leading to numbness, fatigue, spasticity, loss of muscle control, and various other debilitating symptoms. There are four broad theories concerning the etiology of MS. The immune system, environment, viral infections, and genetics are possible factors attributed to the cause of MS ( Although there are no cures for MS, this disease is not fatal. Advancements in technology and medicine enable people with MS to live 90-95% of the normal life span (Sibley, 12).

What is Spasticity?

Spasticity refers to an increase in muscle tone that causes muscle stiffness or spasms (Sibley, 105). There are two types of spasticity prevalent in people with MS: phasic spasms and a sustained increase in muscle tone. Phasic spasms sub-categorize into two types of spasticity: flexor and extensor. In flexor spasticity, the hips and knees of the person bend forward, due to tightening of the hamstrings. In extensor spasticity, the legs of the patient cross over at the ankles or lock together, with the hips and knees remaining rigid ( Spasms also occur less frequently in the arms, backs, and necks of people with MS. Both types of spasticity debilitate patients and lead to difficulties in performing daily tasks. Phasic spasms disrupt the balance of the patient and can cause severe pain. Steady increases in muscle tone inhibits ambulatory abilities, forcing patients to rely on walkers and wheelchairs for transportation (Sibley, 106).



  The Medical Marijuana Controversy

The use of marijuana for medicinal purposes is a long-standing controversy. For centuries marijuana was prescribed to alleviate symptoms associated with a variety of illnesses. Anti-medical marijuana sentiments began with the Marijuana Tax Act of 1937. In 1970, the Controlled Substances Act banned the use of marijuana completely, categorizing it as a drug with no medicinal value, high abuse rates, and detrimental health effects ( Since 1996, numerous states including California, Alaska, Arizona, Nevada, Oregon and Washington have passed medical marijuana initiatives supporting the right to prescribe marijuana for seriously or terminally ill patients ( The American Public Health Association and the Institute of Medicine represent two organizations that have recently researched and endorsed advancements in the study of medical marijuana. Both groups support the use of marijuana for specific treatments, such as reducing nausea in cancer patients receiving chemotherapy, stimulating the appetites of AIDS victims, and limiting spasticity in MS patients.


How Marijuana Alleviates Spasticity

Research providing the breakdown of all of the chemicals in marijuana and their specific physiological and psychological effects is scarce. When analyzing the medicinal effects of marijuana on spasticity, researchers focus primarily on two main active ingredients in the marijuana plant: tetrahydrocannabinol (THC) and cannabinoids (chemicals related to THC) ( Recently, scientists discovered that cannabinoids closely resemble a chemical in the body called anandamide. Anandamide "turns on" nerve receptors throughout the Central Nervous System that effect motor functioning, nausea, and various other biological functions ( This development suggests that cannabinoids have similar effects to anandamide and justifies further research on the therapeutic value of marijuana for muscle spasms attributed to MS.


Marijuana is taken either by smoking or ingestion. Debates over the form in which marijuana should be administered have recently gained popularity. In 1986, the FDA approved oral THC for use as a medicine ( Doctors hesitate to support smoked marijuana because of the health risks attributed to smoking. However, experiments suggest that smoked marijuana is more effective than oral THC. Smoked marijuana allows THC and other chemicals to be directly absorbed into the blood stream, whereas the liver filters ingested THC before it enters the circulatory system. In addition to being more timely, this filtering process converts THC into a more potent form of the drug and, therefore, causes negative side effects ( Furthermore, it is not known whether THC is the sole contributor of marijuana relieving spasticity. The Institute of Medicine acknowledges that "until a non-smoked, rapid-onset cannabinoid drug delivery system becomes available…there is no clear alternative for people suffering from chronic conditions that might be relieved by smoking marijuana" (, pg. 13). Although there is a demand for extensive research of medical marijuana, current evidence supports its distribution for medical purposes.


Scientific Research:

Medical Marijuana and Its Effects on Spasticity

There are a limited number of scientific studies specifically related to the effect that marijuana has on spasticity in patients with MS. The following four studies, listed in chronological order from the most recent, illustrate the positive correlation found between medical marijuana and reduced spasticity in patients with MS.

Meinch, Schonle, and Conrad found that cannabinoids might have beneficial effects on spasticity (Meinch et al, 1989). They performed a case study of a 34 year old male diagnosed with MS. The patient suffered from ataxia and spastic tetraparesis. The goal of their research was to determine a relationship between smoking marijuana and levels of spasticity and ataxia in multiple sclerosis victims. The patient was hospitalized from 17 October to 25 October. On 22 October the patient was given one experimental marijuana cigarette. There were a number of different research methods implemented in this study. The researchers used quantitative clinical and electrophysiological assessments to determine the effects of the smoked marijuana. They repeated each evaluation five to ten times before and after the patient smoked the marijuana cigarette (Meinck et al., 1989).

The results indicated that smoking marijuana might have beneficial effects on both ataxia and spasticity. Before smoking, the patient could not walk, showed reflex patterns indicating spastic paresis, and experienced hand and finger tremors. Within two minutes of inhaling the cigarette, the severity of these disabilities declined. The patient was able to walk several feet, had alleviation from muscle spasms, and no longer experienced tremors in his fingers and hands (Meinch et al, 1989). The researchers encouraged further examinations and studies regarding the effects of medical marijuana. They concluded that the results of their experiment justify the need for continued research.

The second study examines the effect of Delta-9-THC on spasticity associated with MS (Ungerleider et al, 1988). This study was a double blind, placebo controlled, crossover clinical experiment of delta-9-THC in patients with clinical MS and spasticity. The researchers used 13 subjects, consisting of 5 males and 8 females. The patients ranged in age from 26-64 years and were divided into two groups depending on when they experienced their most severe spasticity. They received medications according to these times (one group received medications in the evenings before they went to bed and the second group received medication during the day and at night). The groups were assigned in paired double blind crossover trials. "Patients were given the drug orally for five consecutive days, were drug free for two subsequent days and then received a five day trial with the crossover drug" (Ungerleider et al., 1988). Patients were given appropriate amounts THC, depending on their responses to the drug. If spasticity was not effected and they experienced no side effects, the researchers increased in the following trial. The experimenters used a variety of research methods. They clinically assessed motor functions before, during, and after exposure to TCH. Motor functions included limb weakness, limb spasticity, limb coordination impairment, gait impairment, and reflexes. Each patient was also examined by neurologists before, during, and after they were administered TCH. The researchers also gave the patients questionnaires every morning. The patients rated their levels of spasticity and the side effects experienced while on the medicine (Ungerleider et al., 1988).

The results of this study indicated that the levels of spasticity reported by the patients decreased as the dose of THC increased. Furthermore, clinically assessed spasticity declined significantly when the patients received THC verses when they received a placebo. Although patients reported side effects from higher doses of THC, the results were not significant. The researchers suggested that further research should analyze specific and precise dosages for oral THC to minimize side effects. They also concluded that determining the addiction potential of oral THC should be a goal of future studies. The experimenters asserted that their positive findings imply a future role of THC in the treatment of spasticity in patients with MS (Ungerleider et al., 1988).

The third study, performed by Clifford in 1983, assessed the effects of THC for tremors associated with MS. Clifford’s goal was to validate the claims of a man who asserted that smoking marijuana reduced his spasticity from MS. Clifford examined 8 people who also suffered spasticity from MS. The patients included four men and four women, ranging in age from 21 to 49 years. Clifford videotaped each patient showing "the movement disorder at rest, speech, finger-nose-finger test, heel-knee-shin test, gait when possible, and when picking up a coin with either hand, using a spoon, using a pencil, handwriting a sample of his or her name, and drawing a spiral" (Clifford, 1983). He also performed a brief mental status examination. Finally, he recorded the psychological and physical effects as determined by the patient. Clifford administered a test dose of THC and increased the doses until unbearable side-effects were experienced or there was a therapeutic response. He used a single-blinded placebo to distinguish objective and subjective responses.

Two of the patients in this study experienced improved motor abilities after administration of THC. He described the effect of marijuana on one of these patients: "Tremor was maximal in the head and neck and resulted in particular problems eating, because it increased as efforts were made to put food in the mouth…[after ingesting THC] the patient’s ability to write was considerably improved and his use of eating utensils was markedly improved" (Clifford, 1983). Clifford suggested that further research was necessary to better understand the biological causes of tremors and the physiological effects of THC. He also, however, asserted that it is reasonable to research and consider THC when developing therapeutic remedies for spasticity associated with MS.

The fourth study, performed by Petro and Ellenberger in 1981, examines the effects of delta-9-THC on the treatment of human spasticity. Petro and Ellenberger analyzed nine patients with spasticity related to MS in a double-blind study. Each patient received ether a 5 or 10mg dose of oral THC or a placebo once a day on three different occasions. A blind examiner rated reflexes, resistance to stretching, and abnormal reflexes. The examiner also recorded levels of walking ability and the patient’s subjective responses to the medication and side effects (if present). Examinations occurred before and at 1½-hour intervals after administration of the "medicine" (Petro and Ellenberger, 1981).

The results of this experiment indicated a positive correlation between THC and the reduction of spasticity. Four patients experienced significant improvements in spasticity after administration of THC. None of the patients reported severe side effects. Petro and Ellenberger revolutionized scientific and medical thinking on the possibilities of marijuana as medicine for MS patients. The researchers noted that they "were not able to find previous studies of the effects of marijuana on spasticity in the medical literature" (Petro and Ellenberger, 1981). Based on their results, they concluded that THC should continue to be studied as a possible therapeutic treatment for spasticity.


  Potential Health Risks

Associated with Medical Marijuana

The health concerns associated with medical marijuana relate to the same risks associated with smoking any type of tobacco. However, proof to legitimize these concerns has yet to surface. There is no evidence that chronic illnesses result from smoking marijuana. Medical reports have not linked marijuana to typical chronic diseases associated with smoking tobacco, such as lung cancer and emphysema ( Another concern regarding the medicinal use of marijuana is the possibility that patients will develop dependence for THC. The risk of experiencing withdrawal symptoms, however, is possible for patients who rely on any chemical to maintain daily functioning and is not limited to marijuana use. The short-term risks associated with marijuana use consist of dysphoria, diminished psychomotor performance, restlessness, irritability, nausea, and cramping ( Compared with the side effects of other medicines prescribed to MS patients, however, these short-term risks are mild. The Institute of Medicine reported that "except for the harms associated with smoking, the adverse effects of marijuana use are within the range of effects tolerated for other medications… for certain patients, such as the terminally ill or those with debilitating symptoms, the long-term risks are not of great concern" (, pg. 11-12). Risks associated with the use of medical marijuana remain unclear and unsubstantiated.

Is Medical Marijuana the Solution to

Reducing Spasticity in Patients with MS?

Medical marijuana is a justifiable treatment for spasticity in patients with MS. Interviews indicate that many patients choose marijuana over other medicines because they experience minimal side effects and rapid improvements in motor functioning (Grinspoon and Bakalar, pg. 67-80). One man details the positive results he experienced from using marijuana: "Most MS patients grow progressively weaker and more crippled; I have improved…This may seem insignificant to someone who has never been bedridden, crippled, and unable to move or speak, but to me it is a miracle…Compared to the steroids, tranquilizers, and sedatives usually prescribed for MS patients, marijuana is remarkably safe and benign" (Grinspoon and Bakalar, pg. 75). There is a lack of evidence for long-term risks associated with marijuana use. The short-term risks are minimal and short-lived. Studies verify the positive relationship between medical marijuana use and reduced spasticity. Voters are realizing the cruelty associated with robbing a terminally or chronically ill patient from the medicine that most relieves their pain. MS is a chronic disease that can lead to severe pain and disability if untreated. For these reasons, medical marijuana should be available to patients who understand the risks associated with its use. Until medical research develops an equally effective oral drug, marijuana will remain a reasonable option for patients suffering from MS.


Works Cited

Clifford D.B. Annals of Neurology, "Tetrahydrocannabinol for Tremor in Multiple Sclerosis." June 1983; 13 (6): pages 669-671.

Grinspoon, L., Bakalar, J. (1993). Marijuana, the Forbidden Medicine. New Haven: Yale University Press.

Meinck, H.M., Schonle, P.W., Conrad, B. Journal of Neurology, "Effect of Cannabinoids on Spasticity and Ataxia in Multiple Sclerosis." 1989; 236: pages 120-122.

Petro, D.J., Ellenberger, C.E. Journal of Clinical Pharmacology, "Treatment of Human Spasticity with Delta-9-Tetrahydrocannabinol." 1981; 21: 413S-416S.

Sibley, William A. (1996). Therapeutic Claims in Multiple Sclerosis: A Guide to Treatments (4th ed.). New York: Demos Vermande.

Ungerleider, J.T., Andrysiak, Y., Fairbanks, L., Ellison, G.W., Myers, L.W. Advanced Alcohol Substance Abuse, "Delta-9-THC in the Treatment of Spasticity Associated with Multiple Sclerosis." 1988; 7 (1), 39-50.


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