What's myotonic dystrophy type 2?
Myotonic dystrophy type 2 is a common adult-onset disorder caused by a CCTG repeat expansion, marked by myotonia (delayed muscle relaxation) and progressive muscle degeneration.
| Features mapped | 7 |
|---|---|
| Treatments mapped | 1 |
| Published sources | 3 |
| Last reviewed | 2026-08-04 |
Signs and symptoms
Myalgia
Muscle pain (myalgia) is a characteristic feature of myotonic dystrophy type 2, alongside progressive muscle weakness and wasting.
Cataract
Cataracts (clouding of the lens of the eye), often developing early, are among the features that raise clinical suspicion of myotonic dystrophy type 2.
Type II diabetes mellitus
Diabetes is more common in myotonic dystrophy type 2 than in type 1, reflecting the condition's effects beyond muscle.
Skeletal muscle atrophy
Muscle wasting (atrophy) accompanies the progressive muscle weakness of myotonic dystrophy type 2.
Axial muscle weakness
Axial weakness, affecting the neck flexor and trunk muscles, occurs in myotonic dystrophy type 2.
Myotonia
Myotonia (delayed muscle relaxation, such as difficulty releasing a grip) is a characteristic feature of myotonic dystrophy type 2.
Proximal muscle weakness
Proximal muscle weakness, affecting muscles closer to the trunk such as the hips and thighs, is a core feature of myotonic dystrophy type 2.
Treatment and management
What the research describes, not a recommendation. Treatment decisions belong with your clinician.
This covers treatments that appear in the published research mapped here. Investigational and experimental therapies are not included, so their absence is a boundary of this map, not a sign they do not exist.
mexiletine
Mexiletine is used to reduce myotonia (delayed muscle relaxation).
Used to help with: Myotonia.
“…use of mexiletine for the management of childhood…”
How to read the evidence labels
Where this comes from
This guide is built from 3 published source(s). Every claim above links back to one of them. Click any source ID to read the original on PubMed.
Take it further
Printed, source-linked documents built from this condition's graph — ready to bring to an appointment or attach to a coverage request. Every claim carries its published source, the same as this guide.