Spasticity in Multiple Sclerosis: What Meta-Analyses Have Shown and What Has Not Been Tested for Flower

• How much evidence. 2 works from 2018 to 2023, all listed in the table below along with the model.
• What has not been shown. The effect measured in these meta-analyses is based on patient-reported outcomes, not on a scale filled out by the investigator, and the authors themselves call it limited. The evidence pertains to one disease, multiple sclerosis, and
• What you won’t find here. Dosage recommendations or strain indications. The choice is made by the attending physician, and cannabis flower is a substance dispensed only by a doctor’s prescription.
• How to read this. The results of animal studies or cell cultures do not directly translate to a patient taking flower, and the column with the model indicates what the work was actually about.

What Have Studies on Cannabis Shown Regarding Spasticity?

Two meta-analyses of randomized studies describe a measurable but narrow improvement. The first reports a reduction in spasticity of 0.25 standard deviations compared to placebo, the second an odds ratio of improvement equal to 2.41 in patients resistant to standard treatment. Both pertain to multiple sclerosis and preparations with a fixed composition, not flower described by strain name.

Among the eight indications described in this summary, spasticity has the most solid evidence, and it must be stated plainly.

The effect measured in these meta-analyses is based on patient-reported outcomes, not on a scale filled out by the investigator, and the authors themselves call it limited. The evidence pertains to one disease, multiple sclerosis, and to preparations with a fixed composition administered orally or to the mucous membrane of the oral cavity. There are no studies examining cannabis flower described by strain name, either in multiple sclerosis or in spasticity of other origins.

What is Spasticity and Who Was Studied?

Spasticity is a speed-dependent increase in muscle tone that occurs after damage to the upper motor neuron. It manifests as resistance during passive movement and painful spasms. Both meta-analyses included only patients with multiple sclerosis, so they do not speak to spasticity after stroke, spinal cord injury, or in cerebral palsy.

Damage to the corticospinal pathways removes inhibition from the muscles, causing the stretch reflex to become excessive. The patient feels this as stiffness in the limb, painful nocturnal spasms, and difficulty initiating movement. Multiple sclerosis is just one of the causes of such a condition, as spasticity also accompanies the aftermath of stroke, spinal cord injuries, and motor neuron diseases.

Narrowing the evidence to one disease is not a methodological detail. The response to treatment was measured in the 3161 and 1128 individuals who were included in both reviews, all of whom had a diagnosis of multiple sclerosis. Transferring such a result to spasticity of another origin would be a conclusion that neither of these works makes, and the question about flower under a specific name usually arises precisely outside of that one disease. Neuropathic pain has a separate entry in this summary because the evidence for it was collected in different studies and on different patients.

Who Assesses Spasticity in These Studies?

The patient. The improvement reported by both meta-analyses comes from the assessment made by the patient, and the second work refers to this assessment as a numerical spasticity scale. The Ashworth scale, which is filled out by the investigator after passive movement of the limb, measures muscle resistance, not the patient’s feeling, and it is not this scale that provided the cited number.

The modified Ashworth scale assesses the resistance that the muscle offers during passive movement performed by the investigator and assigns it a degree on a short point scale. The assessment made by the patient asks something different: how much stiffness interferes with them during the day. Both measures can diverge in the same study because they define spasticity in two different ways.

A size of 0.25 standard deviations describes a small effect. The confidence interval from minus 0.38 to minus 0.13 lies entirely on the side of improvement, but it is all within the range of small values, so a statistically significant result does not translate into a noticeable change in fortune. The same work provided alongside spasticity an effect for pain equal to 0.17 and for bladder dysfunction equal to 0.11, which is even smaller than that concerning muscle stiffness. Hence the cautious tone of the first meta-analysis. It is worth reading these two things together: those who ask about the scale of benefits receive a different answer than those who ask about the mere fact of its existence.

What Strain Characteristics Matter Here?

No established ones. Neither the chemotype nor the terpene profile of a single strain has been tested in spasticity: both meta-analyses describe preparations with a fixed composition, administered orally or to the mucous membrane of the oral cavity, not flower dispensed in pharmacies under a strain name. The difference between one and the other is the entire content here.

The register describes flower positions by the declared content of active substances, and commercial databases add to this the aroma profile. None of this data has been linked to spasticity in a controlled study, so a statement about a strain chosen for this indication would be a fabrication, not a conclusion.

The data on composition are also not solid ground. Of 145 positions with declared shares of aromatic components, the sum of these shares comes to exactly one hundred in only twelve cases, in six it exceeds one hundred, and the highest reaches 125. The denominator is therefore unknown and different in various summaries, which is why we do not provide shares numerically.

The names under which flower enters circulation are collected in the flower category, and individual aromatic components are described in separate entries of this summary, such as the one dedicated to myrcene. A list of positions currently available in Polish pharmacies is maintained in the summary of available strains.

How Long Does the Effect Last After Vaporization and After Ingestion?

This depends on the route of administration, not on the strain name. The distinction matters here more than usual, as both meta-analyses evaluated preparations taken orally or sprayed on the mucous membrane of the oral cavity, which is a slower route with a longer episode than inhalation from a vaporizer. The following ranges pertain to the entire group of raw material.

The route of administration determines the course more than the strain itself. After vaporization, the substance passes from the lungs to the blood almost immediately, so the first sensations appear after a few minutes, intensity increases for another ten to thirty minutes, and the whole effect wears off within two to four hours. After ingestion, the raw material first passes through the intestine and liver, so the first sensations are awaited from half an hour to two, and the episode lasts six, sometimes eight hours. Hence the most common mistake with oral administration: those who think after thirty minutes that nothing is happening and adjust the dose will receive both doses at once. The above ranges describe the route of administration, not the strain; pharmacokinetic studies for a single cultivar have not been published.

This is important when reading both reviews. Since they measured oral administration and administration to the mucous membrane of the oral cavity, the described course after inhalation from a vaporizer is not what was evaluated in these studies. A separate entry in this summary explains why the setting of the device does not equal the temperature of the raw material itself.

What Does the Doctor Decide, and What Does the Patient?

The attending physician decides everything related to treatment. In Poland, this raw material is dispensed only by a doctor’s prescription, in the Rpw category, and there is no approved list of indications for it, so the doctor determines whether to use it for a specific patient, in what form, and for how long.

Nabiximols, a standardized extract sprayed on the mucous membrane of the oral cavity, have in Poland the status of a registered medicinal product, with an indication limited to spasticity in multiple sclerosis in patients for whom previous treatment has not improved. Cannabis flower does not have such a record in documentation, as it remains a raw material from which a medicine is prepared, not a ready-made preparation with a studied indication.

On the patient’s side remains what no one can do for them: describing their own symptoms, reporting adverse effects, and adhering to the arrangements from the visit. Independent changes in dosage or route of administration go beyond what the doctor has planned. Advertising of prescription medicinal products directed to the public is prohibited, so this text describes the state of evidence and stops there. The availability of individual positions changes over time, as permits for the admission of raw materials are time-limited, and supplies can be interrupted, so the conversation in the office also concerns what can currently be realized in the pharmacy.

What Adverse Effects Were Reported in Studies on This Indication?

More frequent than with placebo. In the systematic review with meta-analysis of 17 randomized, double-blind, placebo-controlled studies, the overall risk of adverse events was 1.72 times higher, and withdrawals from the study due to them were 2.95 times higher. For serious adverse events, the difference was not significant.

Both of these values are odds ratios compared to placebo, not the frequency of a single symptom. They indicate how many times more often an event occurred in the group receiving cannabinoids, and nothing more. Withdrawals from the study are a stronger measure than the mere number of reports, as each one stands behind a decision to discontinue participation. The evidence base for this summary does not carry separate numbers for safety from the 2023 review, so both values above come from the 2018 work.

Reports of adverse effects are collected for a medicinal product with a batch number, not for a strain name, so the following pertains to cannabis flower as a group of raw materials. The most commonly reported effects are dry mouth, red eyes, and increased heart rate. Less frequently described are dizziness upon rapid standing, daytime drowsiness, and transient worsening of short-term memory, as well as anxiety that increases with dosage. The frequencies of these symptoms are not provided numerically, as public summaries for cannabis flower in Poland do not separate them by individual products.

Frequently Asked Questions About Spasticity and Cannabis

Has flower described by strain name been studied in spasticity?

No. Both meta-analyses evaluated preparations with a fixed composition administered orally or to the mucous membrane of the oral cavity. There are no studies for flower dispensed under a strain name, either in multiple sclerosis or in spasticity of other origins.

What does an improvement of 0.25 standard deviations mean?

It means that the difference compared to placebo was small. The standard deviation describes the spread of results in the studied group, and a quarter of that spread is a small shift, although in this meta-analysis it is statistically significant. The authors of the 2018 work called the effectiveness limited.

How does the patient’s assessment differ from the scale filled out by the investigator?

The patient’s assessment describes the feeling of stiffness in daily life, while the Ashworth scale describes the resistance of the muscle during passive movement performed by the investigator. The cited improvement comes from the first of these measures, not the second.

Are nabiximols the same as cannabis flower?

No. Nabiximols are a registered medicinal product with a fixed composition, sprayed on the mucous membrane of the oral cavity. Cannabis flower is a pharmaceutical raw material with a declared content of active substances, without an approved indication.

How often were adverse effects reported in these studies?

In the 2018 review, the overall risk of adverse events was 1.72 times higher than with placebo, and withdrawals from the study due to them were 2.95 times higher. For serious adverse events, the difference was not significant.

Does this text replace a conversation with a doctor?

No. It describes the state of scientific evidence and is not a therapeutic recommendation. The diagnosis, choice of treatment, and its management are determined by the attending physician, and cannabis flower is dispensed only by a doctor’s prescription.

Cannabis flower is a pharmaceutical raw material dispensed by a doctor’s prescription in the Rpw category. The material is informational in nature and does not replace medical advice. The editorial text was prepared by the editorial team of ubucha.pl.