Amyotrophic lateral sclerosis (ALS) is a type of motor neuron disease (MND) that affects the nerve cells in the brain and spinal cord. ALS is the most common form of MND, and the terms MND and ALS are often used interchangeably. MND is a rare condition that progressively damages parts of the nervous system, leading to muscle weakness and visible wasting. The symptoms of ALS usually start with increasingly slurred speech (dysarthria), which might be misdiagnosed as a stroke. As the condition progresses, it may become increasingly difficult to swallow (dysphagia), and the limbs will become weaker. The muscles in the limbs may become thinner, and the person will find it increasingly difficult to move the affected limbs. The limbs may also become stiff, which is known as spasticity. Both muscle wasting and stiffness can also cause joint aches and pains.

There is no cure for ALS, but treatments can help reduce the impact of the symptoms on a persons life. A team of specialists and a GP will care for the person with ALS. Treatments include highly specialized clinics, physiotherapy, exercises to maintain strength and reduce stiffness, and advice from a speech and language therapist.