Cannabis and MS

Cannabis contains chemicals known as ‘cannabinoids’ including tetrahydrocannabinol (‘THC’ for short). People have claimed cannabis helps with some MS symptoms such as muscle spasms and stiffness as well as pain. 

Surveys show significant numbers of people with MS use cannabis to manage their symptoms. Because medically tested cannabis-based treatments aren’t widely available, some people with MS obtain cannabis from other sources.

Cannabis and the law

Cannabis is a class-B controlled drug in the UK. Possessing, producing and supplying it are all illegal. ‘Supply’ includes sharing the drug with someone or giving it (even for free) to friends or relatives. The law doesn’t allow you to use as a defence the fact you were using cannabis for medical reasons. 

More on the penalties related to cannabis: 

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Unwelcome effects of cannabis

Cannabis has many side-effects including: 

  • dizziness
  • sleepiness
  • feeling drunk
  • impaired driving
  • feeling sick
  • increased risk of seizures
  • harm to unborn babies. 

High doses may slow down reaction time, change your blood pressure and heart beat and affect your sight and coordination. Long-term use can affect your lungs, raise your risk of a heart attack, make cancer of the mouth, throat and lung more likely and has been linked to mental health problems. 

If you or your family have a history of mental health problems (eg schizophrenia or bipolar disorder) you shouldn’t use cannabis. It’s possible to become dependent on cannabis, especially if you use it regularly. 

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Smoking and MS

Smoking tobacco is known to speed up how fast someone goes from having relapsing MS to secondary progressive MS. No studies have yet looked at whether smoking cannabis with tobacco also has this effect, but you should bear this possibility in mind.

Some studies of people with MS who regularly smoke cannabis show they do worse in tests measuring their memory and how fast they process information. MRI scans have also shown abnormal brain activity. None of this is seen in people who use the cannabis-based drug Sativex.

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Sativex is a cannabis-based drug for treating uncontrolled muscle movements (spasm) and muscle stiffness (together known as ‘spasticity’). Sativex is an oral spray containing ‘cannabinoid’ chemicals taken from cannabis plants. It’s sometimes called nabiximols.

More on Sativex.

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