Myotonic Dystrophy

Also known as: DM

What is myotonic dystrophy?

Myotonic dystrophy is the most common form of adult-onset muscular dystrophy. It causes episodes of muscle contractions (myotonia), muscle weakness and loss of muscle mass (wasting) over time.

What causes myotonic dystrophy?

Genetic mutations are responsible for myotonic dystrophy. It’s a hereditary disorder, which means it’s passed down from parents to their children.

What are the symptoms of myotonic dystrophy?

The primary symptoms of myotonic dystrophy are the three characteristics of period episodes of tense, locked-up muscles (myotonia), weakened muscles, and muscle wasting, or the loss of muscle mass over time. Other symptoms may vary depending on what type is present and can include heart problems, facial changes, slurred speech, intellectual disability and more.

How can myotonic dystrophy affect children?

Though myotonic dystrophy is a common form of muscular dystrophy for adults, several forms of the disease start in children or can even be present at birth. Some can cause symptoms in babies when they are born.

What are myotonic dystrophy treatments?

There is no cure for myotonic dystrophy, so treatments are focused on managing symptoms. This may include medications, physical and occupation therapy, speech therapy, surgeries, the use of a CPAP machine and more.

Reviewed by: Migvis Monduy, MD

This page was last updated on: 4/8/2026 4:15:52 PM