ALS is a progressive neurodegenerative disorder without cure or known treatment that significantly improves function. Loss of motor neurons in the brain and spinal cord of ALS patients causes the progressive symptoms. Laboratory studies have linked inducible nitric oxide synthase (iNOS) and caspase enzyme activation to motor nerve cell death in ALS. Minocycline-a medication currently approved by the FDA for treatment of bacterial infections-is a tetracycline antibiotic with high central nervous system penetration when taken orally. The drug inhibits the activity of iNOS and caspase enzymes.