You’ve probably heard of multiple sclerosis (MS) and amyotrophic lateral sclerosis (ALS), also known as Charcot’s disease or Lou Gehrig’s disease. Both conditions affect the nervous system, but they differ significantly in their causes, symptoms, and progression. Today, we want to clarify these distinctions to better guide, raise awareness, and support the community.
Our mission is to accompany affected individuals and their loved ones at every stage of the disease by providing tailored services and resources, practical support, and attentive listening. Understanding what ALS is and how it differs from other nervous system diseases helps better grasp the daily challenges faced by those affected and dispels common misconceptions.
Understanding how amyotrophic lateral sclerosis (ALS) affects the nervous system
The word “sclerosis” comes from the Greek skleros, meaning “scar.” In both diseases, nerve tissue degeneration occurs, but the mechanisms are very different:
- In multiple sclerosis, the immune system attacks myelin, the protective sheath surrounding nerve fibers.
Result: Signals between the brain and the rest of the body are disrupted, causing motor, sensory, and sometimes cognitive difficulties.
- In amyotrophic lateral sclerosis, it is the motor neurons themselves—the cells that control voluntary movements—that degenerate.
This gradually leads to muscle paralysis affecting mobility, speech, swallowing, and breathing.
Key differences between MS and ALS
| Feature | Multiple Sclerosis (MS) | Amyotrophic Lateral Sclerosis (ALS) |
| Type of disease | Neurological disease* According to the Multiple Sclerosis Society of Canada: “Multiple sclerosis is a neurological disease affecting the central nervous system.” It is believed to be an autoimmune disease, where the immune system—normally responsible for defending the body against foreign invaders like bacteria and viruses—attacks the body’s own tissues by mistake. *Learn more about MS: About Multiple Sclerosis | Neurodegenerative |
| Causes | Autoimmune disease triggered by an unknown factor (virus, genetics, environment) | Poorly understood. About 10% of cases are hereditary |
| System affected | Central nervous system (brain and spinal cord) | Motor neurons (brain and spinal cord) |
| Main symptoms | Persistent fatigue, motor issues (weakness, balance problems), numbness or tingling, visual disturbances (double or blurred vision), cognitive difficulties (memory, concentration) | Progressive muscle weakness, loss of mobility and gradual paralysis, difficulty speaking (dysarthria) or swallowing (dysphagia), muscle wasting, respiratory involvement in advanced stages |
| Progression | Relapsing with periods of remission | Progressive and rapid, without remission |
| Population affected | Young adults, mostly women | Middle-aged adults, more often men |
| Life expectancy | Often near normal | Gradual reduction in life expectancy. |
| Treatments | Disease-modifying medications; no cure for MS currently | No curative treatment; some medications can slow disease progression*. *Learn more about the current treatments available: Diagnosis and Treatments |
Why the distinction between MS and ALS matters
Receiving a precise and timely diagnosis is essential to ensure appropriate care and access to disease-specific resources. It also allows for a better understanding of affected individuals’ needs and effective support from the very beginning of their journey.
Recently diagnosed with ALS? Join our community to find support and tailored resources: Start here
The importance of research for neuroinflammation and neurodegenerative diseases
Research into neuroinflammation and neurodegenerative diseases is rapidly advancing. Understanding the common mechanisms between ALS and MS could lead to new therapeutic approaches that benefit multiple brain diseases. Every discovery brings researchers closer to a shared goal: better diagnosis, treatment, prevention, and ultimately, cures.
Discover the importance of research and current advancements: ALS research overview
How ALS Quebec can help you
We are proud to be the reference for families affected by amyotrophic lateral sclerosis (ALS) in Quebec, supporting both individuals with ALS and their loved ones. Our priority is accompaniment—we are here to support them.
We offer:
- Support groups for both patients and caregivers, providing a safe, welcoming, and essential space to break isolation and form connections;
- Reliable, up-to-date ALS resources;
- Professional and peer-to-peer support in both group and individual settings;
- Various initiatives to assist with daily living;
- Social activities and events throughout the year.
🔎 Discover our programs and services and connect with a supportive community for people affected by ALS: ALS Quebec’s Services & Resources
ℹ️ To learn more about multiple sclerosis: About MS