compounds for treatment of some of
these same problems.
Research now suggests that multiple
sclerosis could join the growing list of
cannabis-treated ailments. More than a
dozen medical trials in the past decade
have shown that treatments containing
THC (and some that combine THC with
another derivative called cannabidiol, or
CBD) not only ease pain in MS patients
but also alleviate other problems associated with the disease. MS results from
damage to the fatty sheaths that insulate
nerves in the brain and spinal cord.
“MS patients get burning pain in the
legs and muscle stiffness and spasms
that keep them awake at night,” says
John Zajicek, a neurologist at the Peninsula College of Medicine and Dentistry
in Plymouth, England. Patients can take
potent steroids and other anti-inflammatory drugs, but the effects of these
medications can be inconsistent.
Pertwee has analyzed 17 trials in
which MS patients received some form
of cannabis or its derivatives. Reports
from the patients themselves, who didn’t
know if they were getting real cannabi-
noids or a placebo in most of the trials,
show improvements in muscle spastic-
ity, sleep quality, shakiness, sense of
well-being and mobility. Pertwee, who
is also a consultant for GW Pharma-
ceuticals — which makes a cannabinoid
drug that is delivered in spray form,
called Sativex — reviewed the findings
in Molecular Neurobiology in 2007.
CBD, the same cannabis component that
proved beneficial alongside THC for MS,
may also work on other hard-to-treat
Expanding its reach scientists are investigating cannabinoids’ potential against previously
unconsidered medical problems — including inflammation, crohn’s disease and Ms (shown below).
Cannabis derivatives versus multiple sclerosis
Placebo Marinol capsule (THC) Cannador capsule (THC and CBD)
Percent reporting improvement
source: zaJicek et al./JNNP 2005
diseases. Tests on cell cultures and lab
animals have revealed that CBD fights
inflammation and mitigates the psychoactive effects of THC.
Crohn’s disease, which can lead to
chronic pain, diarrhea and ulcerations,
could be a fitting target for CBD. In
Crohn’s disease, inflammatory proteins damage the intestinal lining, causing leaks that allow bacteria in the gut
to spread where they shouldn’t. This
spread leads to a vicious cycle that can
trigger more inflammation.
Karen Wright, a pharmacologist at
Lancaster University in England, and
her colleagues have found that CBD
inhibits this inflammation and can
reverse the microscopic intestinal leakiness in lab tests of human cells. Adding
THC doesn’t seem to boost the benefit,
Wright reported in December 2009 in
London at a meeting of the British Pharmacological Society. The results bolster
earlier findings by Wright’s team showing that cannabinoids could improve
wound healing in intestinal cells.
CBD’s anti-inflammatory effect may
work, at least in some cases, through its
antioxidant properties — the ability to
soak up highly reactive molecules called
free radicals, which cause cell damage.
In the brain and eye, CBD slows the
action of microglia, immune cells that
can foster harmful inflammation when
hyperactivated by free radicals. Working
with rats whose retinas were induced to
have inflammation, biochemist Gregory
Liou of the Medical College of Georgia
in Augusta and his team found that CBD
neutralized free radicals, preventing eye
damage. This finding could have implications for people with diabetes who
develop vision loss.
Apart from being an anti-inflammatory and antioxidant, CBD tones down
the psychoactive effect of THC without eliminating its medical properties.
CBD also mutes the occasional anxiety
and even paranoia that THC can induce.
This has been welcome news to scientists,
who consider the “buzz” of cannabis little
more than psychoactive baggage.
But CBD has paid a price for this anti-upper effect. “CBD has essentially been