cbd oil for ms tremors

CBD for MS (Multiple Sclerosis): What The Research Says

MS is a disorder involving the loss of insulation around the nerve fibers.

Learn how CBD can support symptoms & may be able to slow the progression of the disease.

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Multiple sclerosis (MS) is a debilitating neurodegenerative disorder affecting two and a half million people around the world.

Cannabis extracts have recently been investigated for their potential role in treating the disease and its symptoms — and the results are promising.

In this article, you’ll learn how CBD and THC are used as a treatment for MS and its symptoms, and the limitations of this all-natural approach.


Carlos G. Aguirre, M.D., Pediatric Neurologist

Updated on November 14, 2021

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Can CBD Oil Help With MS? What Are The Benefits?

A pharmaceutical preparation of CBD (cannabidiol) and THC (delta-9-tetrahydrocannabinol) — Sativex® — was approved by the FDA in 2018 as a treatment for multiple sclerosis.

Sativex® (a pharmaceutical combination of CBD and THC) was shown to improve muscle spasms [7, 8, 9], bladder dysfunction [10], and nerve pain [11] — all of which are common symptoms of MS.

CBD has also been shown to inhibit the ability for immune cells to attack the myelin sheathing on our nerve cells — which is the primary cause for MS.

It’s important to remember that there is still no cure for MS — CBD and other medications may help slow the progression of the disease and manage individual symptoms.

Benefits of Using CBD for MS
  • Reduces neuroinflammation
  • Reduces muscle spasms
  • Prevents T-cell infiltration & slow disease progression
  • Alleviates nerve pain
  • Resists the development of autoimmunity
  • Supports bladder control

1. Inhibits Brain Inflammation

MS, like many other medical conditions, is characterized by underlying inflammation in the brain and spinal cord. Inflammation itself is extremely complex, often involving dozens of inflammatory messengers each interacting differently with each other.

Researchers have highlighted key inflammatory messengers involved with MS — this is used to drive the development of new treatment options.

In the case of MS, the primary inflammatory markers involved include TNFα, IL-1β, IL-2, IL-6, IL-12, and IFN-γ. CBD has been shown to reduce the activity of all of these inflammatory markers and activate other inflammatory processes in the microglial cells that are found abundantly in the human brain [4, 5, 6].

The overall effect is a reduction in neuroinflammation driving the destruction of the myelin — the primary cause for disease progression.

2. Reduces Muscle Spasticity

A 2012 meta-analysis analyzed a series of clinical trials from 1980 to 2012 to review the effects of CBD and THC on muscle spasticity associated with MS [13].

They found that, overall, CBD and THC extracts were well tolerated and offered improvement in symptoms even in patients who were unable to find relief with conventional anticonvulsant medications.

3. May Prevent T-Cell Infiltration & Slow Disease Progression

MS begins with low-grade inflammation in the brain. Specialized cells known as T-cells pass through the blood-brain barrier and congregate around the nerve fibers.

These T-cells are one of the main components of our immune system. Think of them as our immune soldiers, deployed to fight infection.

In the case of MS, these T-cells decide to attack the myelin sheath around the nerve fibers — destroying and scaring them in the process.

One of the primary aims of treatment is stopping these T-cells from going rogue and attacking the body, and preventing them from being passing the blood-brain barrier.

CBD has been shown to slow the movement of T-cells across the blood-brain barrier and limit the inflammatory reaction involved with the disease [4, 5, 6].

4. Alleviates Nerve Pain

Sativex® was involved in a series of clinical studies to determine its effects on the various symptoms of MS, including nerve pain [12]. This study found that those taking Sativex® had significantly reduced pain scores in the final week of treatment.

In other studies, CBD was demonstrated to be beneficial for various types of pain, including neuropathic pain [14], cancer pain [15], and arthritic pain [16].

Guide to Using CBD for Multiple Sclerosis

CBD is a useful supplement for alleviating symptoms of MS and may even be able to slow the progression of the disease.

Most of the research involving CBD for MS used a combination of CBD and THC at a 1:1 ratio. It appears these two cannabinoids work synergistically together to provide relief from symptoms.

In many countries, products containing THC are illegal. However, MS is one of the few conditions that medical cannabis is generally prescribed for — but this can vary according to your country.

Tips for Getting the Most from CBD for Multiple Sclerosis
  1. Make sure to check the quality of CBD products before buying — poor-quality products often contain contaminants that can make the condition worse. Look for certificates of analysis and companies that use organic hemp.
  2. Avoid relying on CBD gummies for your daily dose of CBD — gummies are high in sugar, which has been linked with MS. Oils, tinctures, or capsules are better options.
  3. Combine CBD supplementation with other diet and lifestyle modifications conducive to alleviating MS symptoms.
  4. Always speak with your doctor before taking CBD or other cannabis products — especially if taking other medications.

Even if you can’t find products containing both THC and CBD, or don’t want the psychoactive effects from the THC, you can still use most CBD products. CBD will provide relief from several key symptoms of MS.

What Type of CBD Products Are Best For MS?

The best option is to source a CBD product made with a full-spectrum extract.

These products include an array of cannabinoids, terpenes, and other phytochemicals from the cannabis plant. Each of these compounds work together to produce the overall effects of CBD oil.

With MS, it’s especially important to find oils that have third-party testing to prove they’re contaminant-free. Contaminants like arsenic, mercury, or cadmium can worsen the condition by causing further damage to the neurons.

There are a few products people with MS are using to support symptoms:

  • CBD Oils — this is the most common form of CBD supplement for MS
  • CBD Capsules — offer the same benefits of CBD oil without the need to do any measuring
  • CBD Gummies — similar to CBD capsules, but rarely available in full-spectrum forms
  • CBD Concentrates — shatters, waxes, and dabs deliver heavy doses of CBD in a small volume
  • CBD Vape Pens — these offer the fastest onset of effects, but have the shortest duration

What’s The Dose of CBD For Multiple Sclerosis?

The dose of CBD can vary from one person to another, so it’s important you take some time to see what works best for you.

With that said, most MS patients, and MS research, used a heavier dose than usual (around 2 mg per kg or more).

Use our CBD oil dosage calculator to help find the optimal dose based on your weight and desired strength of effects.

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What is Multiple Sclerosis (MS)?

MS is an autoimmune condition affecting the myelin insulation around nerve cells.

Without myelin, the nerves can’t transmit messages to the rest of the body or the brain.

The cause of MS is hard to determine in most cases but usually involves underlying autoimmune conditions. Autoimmunity happens when the body’s immune system begins attacking and destroying myelin on the nerve cells in the brain.

There is no cure for MS — most of the treatment options are aimed at slowing progression and easing symptoms.

MS can have different levels of severity from one person to the next — symptoms can be anywhere from mild to severe. However, the lifespan of those affected is generally the same as those without the disease. Some reports suggest a six-year difference between people with MS and those without.

What Are The Symptoms of MS?

  • Difficulty speaking(dysarthria)
  • Involuntary eye movements (nystagmus)
  • Tremors
  • Constipation
  • Sexual dysfunction
  • Visual abnormalities
  • Weakness
  • Spasticity
  • Urinary dysfunction
  • Cognitive impairment
  • Pins and needles
  • Seizures
  • Difficulty swallowing
  • Breathing disorders
  • Itchiness
  • Headaches

What Causes MS?

Roughly 1 in 700 people in the United States will be diagnosed with MS at some point in their lives. These figures are similar in other developed regions of the world. Twin studies on the condition have shown that although there are genetic components to the disease, it goes much deeper than that. With identical twins, if one has MS, the other only has a 30% chance of developing the condition — this is much lower than with other genetic disorders.

It’s hard to determine the individual causes of MS — it’s more than likely the condition is a combination of many different factors.

There are some factors that medical researchers have determined to be related to those affected. We call these risk factors for the condition. The more risk factors are present, the higher the chances of developing MS.

Risk Factors for MS
  • Age(most common between the ages of 20 and 50)
  • Gender(women are more than twice as likely to develop MS than men)
  • Ethnicity(European descent has the highest rate of MS)
  • Genetics(HLA-DR2 gene mutations may develop MS)
  • Vitamin D deficiency
  • Viral infection (EBV, cytomegalovirus, varicella zoster)
  • Other autoimmune conditions or atopy
  • Exposure to heavy metals

Four Different Types of MS

1. Clinically Isolated Syndrome

This is the first episode of MS symptoms. Usually, the first sign of the disease is a sudden onset of symptoms that last more than 24 hours. When this happens only once, it’s referred to as clinically isolated. When these symptoms return, we can begin classifying them as a specific form of MS listed below.

2. Relapse-Remitting MS

This form of MS is characterized by bursts of intense symptoms followed by periods of remission. The condition gets gradually worse over time — often, over many years.

Roughly 85% of people with MS experience this form of the disease.

3. Primary-Progressive MS

This form of MS involves a steady progression of symptoms without remissions. It affects about 15% of MS cases on average.

Primary progressive MS involves a steady attack on myelin, producing a predictable worsening of symptoms over time.

Plateaus may occur from time to time, during which symptoms appear to remain the same for long periods. However, it’s unclear why some cases plateau for a while before continuing their progression. Good MS management will promote plateaus more often, but this isn’t always possible.

4. Secondary-Progressive MS

This is a hybrid of relapse-remitting and primary progressive MS. Symptoms generally start with initial episodes of relapse or remission before transitioning into something with a more steady progression of symptoms.

How Is MS Treated?

The most debilitating symptoms of MS are fatigue, muscle spasms/weakness, and nerve pain. Therefore, the primary treatment aim, aside from slowing the progression of the disease, is to address these symptoms as necessary.

Opiate and corticosteroid analgesics are often used to treat severe cases of pain. Otherwise, other analgesics such as acetaminophen are preferred because they produce fewer side effects and less potential for addiction.

Cannabis extracts — including CBD and THC — are also popular treatments for the pain associated with MS.

Emotional changes are common with the condition, so antidepressants and mood stabilizers are often prescribed.

There’s a chance CBD can interact with certain medications, so always check with your doctor before using it.

Common Medications for Multiple Sclerosis:
  1. Antidepressants — to treat depression as a symptom of the condition.
  2. Anti-inflammatories — TNF-a, NF-kB, eicosanoid synthesis modulators, and glucocorticoids.
  3. Aubagio (Teriflunomide) — used for relapse-remitting MS.
  4. Cannabis extract (CBD) — helps relieve symptoms of MS and may slow the progression of the disease.
  5. Copaxone (Glatiramer) — stops the immune system from attacking myelin.
  6. Corticosteroids — used for acute flare-ups of symptoms.
  7. Interferon beta 1a or 1b — slow the progression of the condition but may cause liver damage.
  8. Mitoxantrone (Novantrone) — suppresses the immune system to stop attacks but can damage the heart.
  9. Tysabri (Natalizumab) — last-resort medication as it can lead to infection in the brain.
  10. Vitamin D — often given because vitamin D deficiency is considered a risk factor.

Final Verdict: Can CBD Help With Multiple Sclerosis?

MS is a slow-progressing neurodegenerative disorder affecting the myelin sheath on the neuron cells. As the myelin breaks down, the neurons lose their ability to transmit electrical signals to other areas of the brain and body.

CBD and THC have both been extensively tested to establish their role in alleviating symptoms of this condition. It appears that an even ratio of the two compounds is going to offer the most benefit, but products containing a high CBD content still have positive effects.

We recommend using a full-spectrum product at the higher end of the dosage scale for this condition. It’s also critically important that your doctor monitors your CBD use to avoid negative interactions with other medications and to ensure the best possible outcome.

Cannabis Can Help MS

Recent findings from a National MS Society study estimate nearly 1 million people in the United States are living with MS. This is more than double the last reported number, and the first national research on MS prevalence since 1975. The society also estimates that 2.3 million people live with MS globally.

As a result, many people are looking for alternative solutions to alleviate their symptoms. At Compassionate Telemedicine, we have seen impressive results for people suffering from MS who use medical marijuana.

If your mutiiple sclerosis treatment isn’t giving you the relief you want, or if you’re newly diagnosed with it, you may be curious about how medical marijuana might help you.

Surveys show that many people with MS already use marijuana, and half or more of them would consider it if it were legal or offered proven benefits. So far, the evidence for that is mixed.

How It Might Help

MS is a disease that attacks your brain, spinal cord, and nerves. The marijuana plant, or Cannabis sativa, has dozens of chemicals that can affect your mind and body.

An influential national group of scientific institutions concluded that marijuana, aka cannabis, is proven or highly likely to help ease stiffness and muscle spasms that are common with MS, at least as measured by self-reported symptoms.

Some evidence suggests that marijuana or its active compounds, called cannabinoids, may ease sleep problems in some people with MS, fibromyalgia, and certain other medical conditions.

But evidence is weak that marijuana or cannabinoids:

  • Improve muscle tightness, or spasticity as measured by a doctor.
  • Help or don’t ease depressive symptoms among people with MS or long-term pain.

However, because marijuana is federally illegal, it is extremely difficult to conduct scientific studies on its medicinal properties

Where to Get It

Marijuana remains illegal under federal law. But more than half the states, including Texas, have legalized cannabis for medical use, with the number doubling in 5 years. If you live here in Texas, your doctor will need to approve or certify you for medical marijuana. That allows you to buy it from a medically endorsed pharmacy or a dispensary.

In addition, in least 20 states and the District of Columbia, recreational pot is legal or treated as a minor infraction.

How to Use It

The best-known compound in cannabis is THC, or delta-9-tetrahydrocannabinol. It’s what gets you high when you smoke, eat, or vape it. In Texas, the only legal forms of low dose THC are lozenges and tinctures (oils taken sublingually).

Another active ingredient is cannabidiol (CBD), which doesn’t make you high. Most states allow limited medical uses of CBD. It most often comes in an oil, which you can rub on painful spots, or as an extract or tincture to put under your tongue. You also can swallow CBD capsules or vape, or inhale, it. People sometimes buy CBD online from sellers without a license for medical marijuana.

Some small studies have suggested that CBD may help lower your pain and inflammation. But more research on humans is needed to know if it actually works.

Whether you smoke pot or dab on CBD oil, you may not always know exactly what you’re using. The FDA doesn’t regulate them, so the THC levels, for example, may vary a lot from one batch of pot to the next. Or you may react very differently to CBD than someone else.

It’s not safe to drive while you’re high on marijuana. Smoking or vaping it also can irritate your lungs, affect your memory, and make it harder to think clearly.

Other side effets may include:

  • Anxious
  • Dizzy
  • Sleepy
  • Sick
  • Depressed
  • Paranoia

You shouldn’t use any cannabis products if you:

  • Are pregnant or breast feeding
  • Have heart disease
  • Ever had psychosis
  • Have Parkinson’s disease

Ask your doctor if and which form of cannabis and its extracts might help you.

What Are the Early Signs of MS?

People with multiple sclerosis (MS) tend to have their first symptoms between the ages of 20 and 40. Usually the symptoms get better, but then they come back. Some come and go, while others linger.

No two people have exactly the same symptoms. You may have a single symptom, and then go months or years without any others. A problem can also happen just one time, go away, and never return. For some people, the symptoms get worse within weeks or months.

Keep track of what’s happening to you. It’ll help your doctor monitor your disease and help her understand how well your treatment works.

Early Signs of MS

For many people, the first brush with what’s later diagnosed as MS is what doctors call clinically isolated syndrome (CIS). This episode of neurological symptoms usually lasts 24 hours. It happens when your immune system mistakenly tells your body to attack myelin, the protective sheath over nerve cells in your brain and spine. You may hear your doctor call this demyelination. It causes scars, or lesions, that make it harder for signals to travel between your brain and your body.

There are two types of CIS:

  • Monofocal episode: You have one symptom.
  • Multifocal episode: You have more than one symptom.

The most common symptoms in CIS are:

Opitc Neuritis: This condition damages the nerve that connects your eye to your brain. It usually affects just one eye, but in rare cases, it involves both. You might notice:

  • Blurry vision
  • Colors appear dull
  • Pain in your eye, especially when you move it

Numbness & Tingling: It usually affects your legs. You might feel:

  • An electric shock-like feeling when you move your head or neck. It may travel down your spine or into your arms or legs.
  • Numbness, often in your face
  • Tingling

Not everyone who has CIS will get MS. The odds are higher if you have lesions in your brain from loss of myelin. If you have another CIS or other MS symptoms later, your doctor will do a test called an MRI that takes a picture of your brain to look for them.

These come from ongoing damage to your myelin. They aren’t pleasant, but your MS treatment team can help you keep most of them under control with medication, rehabilitation, and other tactics. The most common symptoms are:

Bladder and bowel problems: You may have to pee more often, need to go at night, or have trouble emptying your bladder fully. Bowel issues like constipation are also common.

Clumsiness or lack of coordination: MS can make it hard to get around. You might have:

  • Trouble walking
  • A hard time keeping your balance
  • Changes in your gait

Dizziness: You may feel lightheaded. You probably won’t have vertigo, that feeling that the room is spinning.

Emotional changes and depression: It’s tough to adjust to the idea that you have a chronic disease, let alone one that’s hard to predict and that will take a physical toll. Fear of the unknown can make you anxious. Plus the disease damages nerve fibers in your brain, and that can affect your emotions. So can medications, like corticosteroids, used to treat MS.

Eye Problems: In addition to the optic neuritis that comes with CIS, MS can cause:

  • Nystagmus: involuntary eye movements
  • Diplopia: double vision

Fatigue: You may feel very tired. It often comes on in the afternoon and causes weak muscles, slowed thinking, or sleepiness. It isn’t usually related to the amount of work you do. Some people with MS say they can feel tired even after a good night’s sleep.

Heat-related problems: You might notice them as you warm up during exercsie. You could feel tired and weak or have trouble controlling certain body parts, like your foot or leg. As you rest and cool down, these symptoms are likely to go away.

Muscle spasms: They usually affect your leg muscles. They’re an early symptom for almost half the people with MS. They also affect people with progressive MS. You might feel mild stiffness or strong, painful spasms.

Sexual troubles: These include vaginal dryness in women and erection problems in men. Both men and women may be less responsive to touch, have a lower sex drive, or have trouble reaching orgasm.

Speech problems: MS could cause long pauses between your words and slurred or nasal speech. You might have swallowing problems as the disease advances.

Thinking problems: It might be hard to focus from time to time. This will probably mean slowed thinking, poor attention, or fuzzy memory. Some people have severe problems that make it hard to do daily tasks, but that’s rare. MS doesn’t usually change your intellect or ability to read and understand conversation.

Tremors: About half of people with MS have them. They can be minor shakes or so intense it’s hard to do everyday activities.

Trouble walking: MS can cause muscle weakness or spasms, which make it tough to walk. Balance problems, numb feet, and fatigue can also happen.

Unusual sensations: In addition to the pins and needles sensation that’s part of CIS, you might also have severe itching, burning, stabbing, or tearing pains. You could feel a tightness around your ribs or upper belly known as the MS hug. Doctors call these uncomfortable symptoms dysesthesia.

Secondary Symptoms

These are problems created by your primary MS symptoms, not by damaged myelin.

  • Not being able to empty your bladder can lead to a bladder infection.
  • If you have trouble walking and are often fatigued, you’re likely to become less active. That can take a toll on your muscle tone, make your breathing shallow, and even affect your bone density.

Doctors can treat secondary symptoms, but the goal is to avoid them by treating the primary symptoms.

Tertiary Symptoms

These are the social, psychological, and job-related problems of life with MS.

  • If MS makes it hard for you to walk or drive, you may not be able to do your job well.
  • Because it’s tough to get around and hard to talk to people about what life with a chronic disease is like, you may not be as social as you once were.
  • You could get depressed. It’s a byproduct of the changes MS makes in your brain and in your life.

Because MS varies so much, it’s best not to compare yourself with other people who have it. Your experience is likely to be different. Most people learn to manage their symptoms and can keep leading full, active lives.

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Can Low Dose THC Treat Spasticity?

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Cannabis for spasticity and multiple sclerosis

There is only limited evidence mainly from anecdotal reports that cannabis (smoked or oral) benefits spasticity from multiple sclerosis or spinal cord injury. Some randomised N of 1 studies support this. The weight of evidence is not great, and more recent, though small, randomised trials show absolutely no effect, with some adverse effects.

Cannabis is commonly thought to be beneficial to patients with multiple sclerosis, especially those with spasticity. There are no modern randomised double-blind trials of any size, though there is one currently ongoing, whose design and objectives can be seen on the Internet.

The single largest study to investigate the efficacy of cannabis in multiple sclerosis recruited its 667th and last patient on October 10 2002. The first 15 weeks of treatment will be completed in February 2003 and results of the trial are hope to be announced in the summer of 2003.

The trial

It will recruit 660 patients with multiple sclerosis from across the UK who have significant spasticity in some of their leg muscles. Each patient will be randomly allocated to one of three treatments: cannabis oil, tetrahydrocannabinol (a constituent of cannabis) or placebo capsules (containing only vegetable oil).

Patients and doctors will not know which treatment is being taken until after the study, and assessments of muscle stiffness and mobility will be made every few weeks. Side effects will be recorded and patients will be encouraged to reach a certain level of medication over an initial five week period, before an eight-week period of monitoring. Assessments will also be made of quality of life and disability by postal questionnaire.

While we wait for the results of the trial, people still want to know what evidence we have. This snippet examines the evidence to date.


Bandolier therefore set out to examine what evidence does exist, and searched for papers on cannabis (plus its other names) using PubMed and the Cochrane Library, and reviews, and reference lists, and official reports. What we found is given in the Table below, together with the reference for each and a brief summary of what the paper was and found. Some papers are still awaited, and the blanks will be filled in as they arrive. Some we mave to wait some time for. Reviews and peripherally interesting papers are also included.


Most of the results were anecdotal and impossible to interpret. Where test, abstinence and retest had been conducted, sometimes with blinded observations, results were reproducible. This was true also of two N of 1 designs, one of which was randomised, and double-blind, and with identically looking preparations of cannabinoid, codeine and placebo. There are several studies that were randomised and double-blind, but not always examining useful clinical outcomes. Because studies were often very small, and with self-selecting patients who were usually (though not always) previous cannabis users, the small benefits seen must be regarded as disappointing. They could easily be wrong just by the random play of chance.

Oral preparations of cannabinoids helped most, but not all patients, and some seemed only to respond to the smoked version. In the last few years some scientific basis has been adduced to support cannabinoid involvement in the control of spasticity, perhaps with endogenous cannabinoids being involved with maintaining spastic tone.

Table: List of papers around the subject of cannabis and spasticity and MS



This was a randomised crossover trial of placebo, THC and plan extract given orally in sixteen patients with progressive MS and spasticity. Four weeks of treatment with placebo, 2.5-5 mg THC, or plant extract with equivalent THC (identical appearance) was followed by four weeks of washout before the next treatment. A lower dose was used for two weeks, and doubled, if well tolerated, for the second two weeks of treatment.

Active treatments conferred no benefit. Plant extract, but not THC, had significantly more adverse events. Five patients on plant extract reported subjective increased spasticity and one had an episode of acute psychosis.

Best randomised trial to date [1]

This was a randomised crossover trial of placebo, THC and plan extract given orally in sixteen patients with progressive multiple sclerosis and spasticity. Four weeks of treatment with placebo, 2.5-5 mg THC, or plant extract with equivalent THC (identical appearance) was followed by four weeks of washout before the next treatment. A lower dose was used for two weeks, and doubled, if well tolerated, for the second two weeks of treatment.

Muscle tone was measured on a categorical scale (0=normal, 1=slight increase, 2=more marked increase, 3=considerable increase, 4=limb rigidity in flexion or extension) for arms and legs. Patients had to have a score of at least 2 for inclusion. EDSS and several other tests of function and ambulation were used.


Six of the 16 patients had primary and 10 secondary progressive MS. The average age was 46 years, with MS for an average of 15 years, and the mean EDSS score was 6.2. All completed all scheduled visits for all three treatments.

Active treatments conferred no benefit. Plant extract, but not THC, had significantly more adverse events. Five patients on plant extract reported subjective increased spasticity and one had an episode of acute psychosis.


There really are no conclusions to be drawn from this. With case reports we are unlikely to know of many people who have tried cannabinoids and failed, so the bias we find from publication of positive results will be massive. Even the N of 1 trials are done in known responders. There may be patients who respond to cannabinoids and whose spasticity or other symptoms may be allieviated. They may be common, or rare as hen’s teeth. We will have to wait for the results of the ongoing large randomised trial for the bigger picture.

What we do see is that newer studies, or those with better and designs less open to bias, are being more negative. The hope must be (and hope it has to be now) that something in the method of delivery of drug will confer unexpected benefits.

The large UK Cannabis in Multiple Sclerosis study organised from Derriford Hospital in Plymouth will look specifically at the question of whether cannabis, as either whole plant extract or one of its active components, can help the muscle stiffness and spasms that affect multiple sclerosis sufferers. Results are likely to be available in 2003. You can visit the trial site at http://www.cannabis-trial.plymouth.ac.uk/.

The study recruited its 667th and last patient on October 10 2002. The first 15 weeks of treatment will be completed in February 2003 and results of the trial are hope to be announced in the summer of 2003.

1. J Killestein et al. Safety, tolerability and efficacy of orally administered cannabinoids in MS. Neurology 2002 58: 1404-1407.