Medical Marijuana for Multiple Sclerosis Patients

Sweden approves medical ‘marijuana’. Following the lead of drug regulators in Germany, Denmark, the United Kingdom, Spain and four other European countries, Sweden’s Medical Products Agency (Läkemedelsverket) approved a cannabis-based mouth spray for the treatment of multiple sclerosis (MS) on Feb. 12.

Apart from the eight European countries, the cannabis spray is also available in Canada (since 2005) and New Zealand, where it’s been approved for relieving pain and muscle spasms associated with multiple sclerosis.

The mouth spray, called Sativex, has the same active components in ‘street’ pot smoked by people around the world: delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). In particular, it contains Tetranabinex and Nabidiolex, extracts of chemically and genetically characterized Cannabis sativa L., making it the world’s first medication developed from raw marijuana plants. [Related: Sativex Side Effects]

In some European countries, Sativex has also been used to treat moderate to severe pain in advanced cancer, when the highest doses of other pain relievers don’t provide adequate pain relief. And its maker, British pharmaceutical GW Pharma, is expecting the United States Food and Drug Authority to approve the spray by next year (2013) for use as treatment in cancer pain.

“This is great news for those who can’t get any relief from the most common drugs,” Jan Hillert, an MS researcher at Sweden’s Karolinska Institutet tells the Dagens Nyheter daily.

The Swedish drug regulator said it would closely monitor the prescription of the newly-approved drug to ensure it isn’t abused. But it also said this was unlikely since the spray’s cannabis content is so low, users don’t feel any sort of “kick.” In fact, more common than a “high” are side effects like dizziness, nausea and drowsiness.

More than two million people worldwide (about 400,000 in the U.S. and 75,000 in Canada) suffer from multiple sclerosis, a progressive and debilitating degenerative neurological disease.

People who suffer from MS have hyperactive immune systems that attack their own myelin—the fatty tissues that insulates the nerves, allowing these to conduct signals to and from the brain. When the myelin and then the nerves themselves are destroyed, MS sufferers lose many functions controlled by the nervous system.

Beginning with stiffness or weakness in the limbs and blurred vision, as more and more nerves get affected, the other brain functions begin to deteriorate— vision, speech, walking, memory and writing.

Over time, MS victims suffer from spasms and tremors, pain, incontinence, constipation and even difficulty concentrating, memory loss, anxiety and depression.

Neuropathic pain is also one of the more distressing MS symptoms—and Sativex has been shown to effectively block the pain. Its antispasmodic and muscle-relaxant properties also relieve the stiffness and muscle cramps of MS.

In the late 1980s and 1990s, scientists discovered that mammals have receptors for cannabinoids, the chemicals in the marijuana plant. These receptors are found in their central nervous systems, several organs and in their immune systems. Mammal bodies also produce natural cannabinoids that work on the same receptors.

Sativex is thought to stop pain by acting via cannabinoid receptors that are distributed throughout the central nervous and the immune systems.

Marijuana chemicals may slow the progress of MS
Right now, there’s still no cure for multiple sclerosis.

But two U.S. scientists think they’re close to achieving the next best thing—slowing the disease’s progression. Again, marijuana seems to be the key.

Current medications for MS, like corticosteroids, turn off the immune response entirely—but while that stops the distressing symptoms, it also leaves MS sufferers vulnerable to a host of infections.

Calming the immune system may be key to fighting the disease and the cannabinoids in marijuana may be able to do this. That, at least, is what two scientists from Philadelphia’s Temple University think, and they’ve been exploring this approach since 2009, according to a report of the Insciences Journal.

“MS is a terrible disease and the more rapidly it progresses, the sooner it disables its victims,” says co-researcher Dr. Doina Ganea, Earle H. Spaulding chair and professor of microbiology and immunology. “So, if you can slow that down for 10 or 20 years, you can make a significant impact on the patients’ lives,” she says.

The cannabinoids produced by the human body act through specific receptors on immune cells to regulate the immune response. The job of these receptors is to tell the immune system when to turn on and off—or when to fight an infection and when to stand down. But in MS sufferers this function has gone haywire—their receptors are always on alert and their immune system is in constant attack mode.

According to Dr. Ron F. Tuma, Stewart professor of physiology and associate professor of neurosurgery, he and Dr. Ganea are focusing on one of 96 chemicals in the marijuana plant “that doesn’t cause psychoactive effects but does affect the immune system.”

“Our goal is to develop new therapeutic agents in the fight against multiple sclerosis and improve the quality of life for the millions who suffer,” Tuma tells Insciences Journal.

Theorizing that they can manipulate a man-made chemical to act as a cannabinoid and control the activation of those immune cells, the two researchers found that a synthetic cannabinoid affected cannabinoid receptors found mainly in the immune cells of lab animals.

Dr. Tuma and Dr. Ganea found that the synthetic cannabinoid O-1996, made by scientists at the Medical College of Virginia and the company Organix, calmed down the immune system’s hyperactivity in lab animals and significantly reduced damage to their central nervous systems. The findings of their early study were published in the March issue of the Journal of Neuroimmune Pharmacology.