RILUTEK is used in patients with amyotrophic lateral sclerosis (ALS). ALS is a form of motor neurone disease where attacks of the nerve cells responsible for sending instructions to the muscles lead to weakness, muscle waste and paralysis. The destruction of nerve cells in motor neurone disease may be caused by too much glutamate (a chemical messenger) in the brain and spinal cord. RILUTEK stops the release of glutamate and this may help in preventing the nerve cells being damaged. Please consult your doctor for more information about ALS and the reason why this medicine has been prescribed for you.