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Start free with EleplanHyperkalemic periodic paralysis
ORPHA:682Disease
Also called Adynamia episodica hereditaria · Familial hyperPP · Familial hyperkalemic periodic paralysis · Gamstorp disease · Gamstorp episodic adynamy · HYPP · HyperKPP · HyperPP · Hyperkalemic PP · Primary hyperPP · Primary hyperkalemic periodic paralysis
What it is
A rare muscle disorder characterized by episodic attacks of muscle weakness associated with an increase in serum potassium concentration.
Key facts
- Prevalence
- 1-9 / 1 000 000 (Europe)
- Age of onset
- Childhood
- Inheritance
- Autosomal dominant
- Classified as
- Disease
Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.
Signs and symptoms
Very common80–99%
6Sometimes5–29%
18- Arrhythmia
- Bowel incontinence
- Chest pain
- Congestive heart failure
- Death in early adulthood
- Death in infancy
- Feeding difficulties in infancy
- Flexion contracture
and 10 more in this range
These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.
Gene
ICD-10 codes
ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.
Benefit programs to look at
Programs whose eligibility touches the same ICD-10 categories. Eligibility is decided by the administering agency, never by this page.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
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