“Spasticity is a common neurologic condition in patients with multiple sclerosis, stroke, cerebral palsy or an injured spinal cord. Animal studies suggest that THC has an inhibitory effect on polysynaptic reflexes.

Some spastic patients claim improvement after inhaling cannabis. We tested muscle tone, reflexes, strength and performed EMGs before and after double-blinded oral administration of either 10 or 5 mg THC or placebo.

10 mg THC significantly reduced spasticity by clinical measurement (P less than 0.01).

Responses varied, but benefit was seen in three of three patients with “tonic spasms.””