4-Aminopyridine is used to improve motor function in patients with multiple sclerosis (MS) by enhancing nerve signal transmission through inhibition of potassium ion channels, which prolongs action potentials in neurons. This helps counteract muscle weakness and fatigue, leading to better mobility and muscle control.

It is also approved for treating Lambert-Eaton Myasthenic Syndrome (LEMS), a neuromuscular disorder, where it relieves muscle fatigue and improves strength and quality of life.

Investigated for spinal cord injuries due to its ability to restore nerve conduction in damaged tissue. Used in neuroscientific research to study synaptic transmission, potassium channel function, and overall nervous system activity. Serves as a key intermediate in the synthesis of other pharmaceutical compounds, particularly those affecting the central nervous system.