Amyotrophic lateral sclerosis (ALS)

Amyotrophic lateral sclerosis is a progressive disease of the motor neurons controlling voluntary movement, leading to weakness, muscle wasting and eventual loss of speech, swallowing and breathing.

Also known as Lou Gehrig's disease, ALS typically begins in middle or later adulthood with symptoms such as limb weakness, tripping, dropped objects, slurred speech or muscle twitching. Thinking and the senses are usually preserved, although a minority of patients develop frontotemporal dementia. Most cases are sporadic, while a minority run in families through identified gene changes.

There is no single diagnostic test; neurologists combine examination, electromyography, nerve conduction studies, imaging and blood tests to exclude conditions that mimic it. A few approved medications modestly slow progression, and multidisciplinary care addresses breathing, nutrition and mobility. Cannabinoids have been investigated for symptoms such as spasticity and cramps, but direct clinical evidence for cannabidiol in ALS is insufficient.