ORPHA:682
Hyperkalemic periodic paralysis
Also known as: 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
Publications
1,028
86.7th percentile
Trials
4
Interventional, condition-specific
Researchers
956
Distinct authors in sample
Gene link
SCN4A
Definitive
Readiness
3/6
Stages with a signal
Clinical definition (Orphanet)
A rare muscle disorder characterized by episodic attacks of muscle weakness associated with an increase in serum potassium concentration.
How rare: 1-9 / 1 000 000 — roughly one to nine people per million. In a city the size of Kolkata, perhaps a few dozen.
Cross-references
Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.
- MONDO:0008224
- MeSH:D020513
- OMIM:170500
- UMLS:C0238357
- NCIT:C123429
Additional Mondo synonyms (13)
adynamia episodica hereditaria · adynamia episodica hereditaria with or without myotonia · familial hyperPP · familial hyperkalemic periodic paralysis · familial hyperkalemic periodic paralysis (disorder) [ambiguous] · hyperKPP · hyperPP · hyperkalemic PP · hyperkalemic periodic paralysis · hyperkalemic periodic paralysis, type 2 · normokalemic periodic paralysis, potassium-sensitive · primary hyperPP · primary hyperkalemic periodic paralysis
Research stages
Trial readiness signals
Where this condition sits on an open-data research pipeline — not how close a treatment is, and not medical advice. Empty stages often mean “not in these databases under this Mondo ID,” not “impossible.”
3/6 stages with a signal
An interventional trial matched this condition name on ClinicalTrials.gov — see trials below.
- Gene identifiedPresent
Definitive — SCN4A
- LiteraturePresent
1,028 matched papers (349 in last 10 years) Source
- Phenotype characterisedNot checked
Not yet enriched from Monarch / HPO
- Animal modelNot checked
Not yet enriched from Monarch / Alliance
- Orphan designationNot checked
FDA/EMA orphan-drug designation not enriched yet
- Interventional trialPresent
4 matched on ClinicalTrials.gov (2 recruiting in sample)
Biology
Genes and phenotypes
Gene–disease validity from GenCC, plus phenotypes and animal models joined from Monarch Initiative via Mondo ID — not a clinical diagnosis aid.
Do we know what causes it?
Yes — we know a specific gene responsible (SCN4A).
GenCC classification: Definitive.
Phenotypes (Monarch / HPO)
Not enriched in this build — Monarch phenotype joins were not run for this record.
Animal models (Monarch / Alliance)
Not enriched in this build.
Literature
Is anyone studying this?
1,028
1,028 papers have been published on this condition. That is a real research literature — still far smaller than common diseases (breast cancer: over 700,000 papers). Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=5449) is 41.
1,028 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 41 (publications denominator n=5449).
349 in the last 10 years · medium confidence · 86.7th percentile (publications denominator)
Phrase hits: 1,028 · MeSH hits: 0
Who's working on it?
956
Distinct author names in 200 sampled papers — named people below.
Who's working on it?
People publishing on this condition (sampled Europe PMC records). Affiliation is the most recent found in that sample.
- 01Hanna MG13 papers · 2025
MRC Centre for Neuromuscular Diseases, Department of Neuromuscular diseases, UCL Queen Square Institute of Neurology, United Kingdom.
Papers in Europe PMC - 02Cannon SC8 papers · 2025
Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California.
Papers in Europe PMC - 03Finno CJ7 papers · 2026
Department of Population Health and Reproduction, School of Veterinary Medicine, University of California-Davis, Davis, California, USA.
Papers in Europe PMC - 04Jurkat-Rott K7 papers · 2017
Division of Neurophysiology, University of Ulm, 89069 Ulm, Germany.
Papers in Europe PMC - 05Matthews E7 papers · 2023
MRC Centre for Neuromuscular Diseases, Department of Neuromuscular diseases, UCL Queen Square Institute of Neurology, United Kingdom.
Papers in Europe PMC - 06Kubota T6 papers · 2026
Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan.
Papers in Europe PMC - 07Lehmann-Horn F6 papers · 2017
Division of Neurophysiology, Ulm University, Germany.
Papers in Europe PMC - 08Vivekanandam V6 papers · 2024
MRC Centre for Neuromuscular Diseases (KJS, VV, NJ, SH, DF, MGH, ELM), Queen Square Institute of Neurology, UCL and National Hospital for Neurology and Neurosurgery; and Neurogenetics Unit (RS), National Hospital for Neurology and Neurosurgery, Queen Square, London, UK.
Papers in Europe PMC - 09Bellone RR5 papers · 2026
Department of Population Health and Reproduction, Veterinary Genetics Laboratory, School of Veterinary Medicine, University of California Davis, Davis, California, USA.
Papers in Europe PMC - 10Hayward LJ5 papers · 2020
Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01655.
Papers in Europe PMC
Clinical research
Is a treatment being tested?
4
interventional trials for this specific condition
4 interventional trials matched this specific condition name; 2 currently recruiting in our sample. 2 trials are registered for periodic paralysis, the broader category — shown separately because they may or may not enrol this specific subtype.
Data as of 27 July 2026
4 interventional trials — more than 73% of diseases in the trials denominator have none at all (5114 of 7003; this disease is at the 86.7th percentile).
medium confidence · 86.7th percentile (trials denominator)
Recruiting interventional trials
From the matched ClinicalTrials.gov set
4 interventional trials matched after quoted-phrase search and title/condition post-filter.
- NCT07183059·NOT YET RECRUITING·A Single Center Prospective Study in an Estimated 570 Patients Who Underwent Genetic Screening at UZ Brussel in the Context of a Primary Cardiac Arrhythmia. Patients Showing a Variant Class 3,4 or 5 in SCN4A or CLCN1 Will Undergo a Clinical and Electrophysiological Review After IC.
Conditions: Non Dystrophic Myotonia · Arrythmia, Cardiac·Matched via recall expansion
- NCT07194174·RECRUITING·Effect of Physical Training in Individuals With Hypokalemic and Hyperkalemic Periodic Paralysis
Conditions: Hypokalemic Periodic Paralysis · Hyperkalemic Periodic Paralysis·Matched via name phrase
Broader category: periodic paralysis
2
Interventional trials for the parent category, exclusive of NCT IDs already counted above. Eligibility for this subtype is not guaranteed.
Worth raising with a clinician. How we count trials.
Where to find support
We do not yet link condition-specific patient organisations. These umbrella groups support undiagnosed and ultra-rare families:
India — NPRD
Last verified 2026-07-26This ORPHAcode is not on our curated NPRD list (direct or Mondo-parent match). That does not decide clinical eligibility; families in India should ask a notified Centre of Excellence about current coverage.
Hand-curated for this project. ORPHAcode mappings are best-effort and may be incomplete or imprecise for umbrella categories. Parent (Mondo) matches mean the policy lists a broader category — confirm eligibility with a Centre of Excellence. Financial entitlements summarised from public policy statements and may change. This is not official government guidance.
How we counted this
Europe PMC query (preferred label + any corrected label + Orphanet and Mondo exact synonyms, stoplisted; unioned with resolved MeSH labels when available). UMLS / OMIM / NCIT cross-references are stored on the overview but are not added to the query string.
"Hyperkalemic periodic paralysis" OR "Adynamia episodica hereditaria" OR "Familial hyperPP" OR "Familial hyperkalemic periodic paralysis" OR "Gamstorp disease" OR "Gamstorp episodic adynamy" OR "HyperKPP" OR "HyperPP" OR "Hyperkalemic PP" OR "Primary hyperPP" OR "Primary hyperkalemic periodic paralysis" OR "adynamia episodica hereditaria with or without myotonia" OR "familial hyperkalemic periodic paralysis (disorder) [ambiguous]" OR "hyperkalemic periodic paralysis, type 2" OR "normokalemic periodic paralysis, potassium-sensitive"
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Hyperkalemic periodic paralysis" OR "Adynamia episodica hereditaria" OR "Familial hyperPP" OR "Familial hyperkalemic periodic paralysis" OR "Gamstorp disease" OR "Gamstorp episodic adynamy" OR "HyperKPP" OR "HyperPP" OR "Hyperkalemic PP" OR "Primary hyperPP" OR "Primary hyperkalemic periodic paralysis" OR "adynamia episodica hereditaria with or without myotonia" OR "familial hyperkalemic periodic paralysis (disorder) [ambiguous]" OR "hyperkalemic periodic paralysis, type 2" OR "normokalemic periodic paralysis, potassium-sensitive" OR "SCN4A"
Recall-expansion terms: SCN4A
Interventional trials matched via: phrase, recall-expansion (mesh = registered under a MeSH descriptor no name phrase would catch; recall-expansion = gene / selected parent terms used only for trials).
Study-type breakdown: 4 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.
Parent-category trials query:
"periodic paralysis"
Query health: ok — strategies attempted: phrase, recall-expansion; with hits: phrase, recall-expansion
Run this search on ClinicalTrials.gov
Synonyms dropped by stoplist: HYPP
Confidence reasoning
- Preferred label is multi-word and distinctive
- 1 synonym(s) dropped by stoplist (may under-count)
- No label/synonym collisions with other diseases in this corpus
Ingested 2026-07-26T14:55:36.347Z