Tiglutik is used to treat a type of nerve disease called amyotrophic lateral sclerosis (ALS, also commonly called Lou Gehrig's disease). Riluzole in Tiglutik helps slow the progression of this disease and prolong survival. However, it is not a cure for amyotrophic lateral sclerosis, and it does not reverse nerve damage or muscle weakness.

Amyotrophic lateral sclerosis, also known as ALS, is a degenerative motor neuron disease caused by damage to peripheral motor neurons combined with damage to the pyramidal system that can cause loss of sensation. Amyotrophic lateral sclerosis eventually leads to death due to paralysis of the respiratory muscles, respiratory complications (aspiration pneumonia...) or other complications due to immobility.