ALS is a disorder that weakens motor strength and lung function. Rapid loss of motor neurons in the brain and spinal cord of ALS patients causes the symptoms of increasing weakness and loss of muscle function. Motor neurons are responsible for sending signals to muscles in our bodies to trigger movement. While there are drugs to help relieve symptoms of ALS, there is no cure for ALS. Rasagiline is a drug with possible neuroprotective characteristics. Neuroprotective means that the nervous system may be protected against weakening. It is known that rasagiline has possible neuroprotective characteristics, but the effectiveness of rasagiline for patients with ALS has not been tested. Rasagiline is approved for the treatment of Parkinson's disease. Rasagiline for treatment of ALS is not approved by the U.S. Food and Drug Administration (FDA) and is investigational. Investigational drugs are studied to find out if they are safe and effective in the treatment of diseases or conditions. By doing this study, researchers hope to learn if rasagiline is safe and slows disease progression in patients with ALS. Funding Source - FDA OOPD (FDA Orphan Products Division).