A cannabis-based drug may help ease muscle movement for people suffering from motor neuron disease the results of a clinical trial have shown. The study published in The Lancet Neurology journal showed that chemical compounds -- delta-9 tetrahydrocannabinol THC and cannabidiol (THC-CBD) -- derived from the cannabis sativa plant given as an add-on treatment may help ease symptoms of spasticity (tight or stiff muscles). Spasticity is a rapidly progressive fatal neurodegenerative disorder affecting the nerve cells that control muscle movement. It is a major cause of disability and reduced quality of life in people with motor neuron disease. Adults with