What is Primary Periodic Paralysis?

Primary Periodic Paralysis is a rare autosomal-dominant disease characterized by severe episodes of muscle weakness concomitant to variations in blood potassium levels.

There are four main types of Primary Periodic Paralysis, which are all channelopathies (diseases caused by mutations in genes encoding ion channels). The culprit genes encode for potassium, calcium, and sodium channels. It is usual to differentiate hypokalemic and hyperkalemic periodic paralysis.1

The four main types of Primary Periodic Paralysis are:

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Hypokalemic Periodic Paralysis – This is the most common type of Primary Periodic Paralysis. Patients have low serum potassium levels. Paralytic attacks can be worsened by low temperature, anxiety, excessive salt ingestion, lack of exercise, consumption of glucosteroids or alcohol, and anesthetic methods.1 Hypokalemic Periodic Paralysis is estimated to affect 1 in 100,000 people.2

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Hyperkalemic Periodic Paralysis – Patients have high serum potassium levels. A paralytic attack can be triggered by potassium-rich food or post-exercise rest and be intensified by low temperature and emotional stress.1 Primary Hyperkalemic Periodic Paralysis occurs in around 1 in 200,000 people.2

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Andersen-Tawil Syndrome - Also known as cardiodysrhythmic periodic paralysis or potassium‐sensitive periodic paralysis. Cardiac arrythmias occur alongside paralytic attacks. Potassium doesn’t move in and out of the cells properly. Both low and high serum potassium levels can trigger attacks. Low temperatures and exercise are also triggers.1 Anderson-Tawil only affects 1 in 1,000,000 people worldwide.3

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Paramyotonia Congenita – Also known as sodium channel myotonia, is estimated to affect 1 in 100,000 people worldwide.4 Paramyotonia Congenita causes mutations in the muscle sodium channel gene to prolong the channel’s opening, causing higher-than-normal muscle excitation. The overexcitation of muscles during brief exercise can trigger stiffness in the muscles and prolonged overexcitation can lead to fatigue-like weakness.5 The most commonly affected muscles are located in the face, neck and upper extremities, although it can affect the muscles used for breathing and swallowing, as well as muscles in the lower back.6

Symptoms of Primary Periodic Paralysis

Symptoms typically begin in the first or second decade of life. Attacks of flaccid paralysis (weakness) usually occur on awakening in the night or in the early morning. Weakness may be focal or generalized, usually sparing facial and respiratory muscles, and lasting for hours (occasionally days) with gradual resolution. Frequency of individual attacks can vary from daily to a few episodes in a lifetime; attacks often decrease in frequency after age 40.7

Triggers of Primary Periodic Paralysis episodes

Whilst each type of Primary Periodic Paralysis has its own triggers, strenuous activity, stress and extreme temperatures are triggers for all types of Primary Periodic Paralysis.8

Nutrition has been widely described as a trigger for Primary Periodic Paralysis, and by a patient understanding their triggers, the likelihood of an attack is lowered. Dietary needs vary based on the type of Primary Periodic Paralysis a patient has and their individual needs.8

Hypokalemic Periodic Paralysis – Paralytic attacks can be worsened by low temperature, anxiety, excessive salt ingestion, lack of exercise, consumption of glucosteroids or alcohol, and anesthetic methods.9

Hyperkalemic Periodic Paralysis – A paralytic attack can be triggered by potassium-rich food or post-exercise rest and be intensified by low temperature and emotional stress.9

Andersen-Tawil Syndrome – Both low and high serum potassium levels can trigger attacks. Low temperatures and exercise are also triggers.9

Patients with Paramyotonia Congenita benefit from low potassium diets.10 Patients should also avoid skipping meals and take carbohydrate rich snacks in between meals.11

Impact of Primary Periodic Paralysis on patients

Having a rare disease can make your patients feel isolated, stressed, and anxious. Patients with Primary Periodic Paralysis have reported that their condition has negative impacts on:

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Work (68.3 %)

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Overall physical health (59.8 %)

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School (57.3 %)

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Family life (37.8 %)

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Overall mental health (30.5 %)

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And relationships (25.6 %)4

With ORMALVI™ (dichlorphenamide) tablets, it’s time for your patients. Our product support program, Cycle Vita™, is available to eligible* patients with Primary Periodic Paralysis.

Find out more about patient support

Do you have a patient with suspected Primary Periodic Paralysis?

The diagnosis of Primary Periodic Paralysis can be confirmed by genetic testing, which is recommended as the first diagnostic step when there is an intermediate-to-high clinical suspicion.

Find out more

References

  1. Fontaine, B. (2008). Chapter 1 Periodic Paralysis. Advances in Genetics, [online] pp.3–23. Available at: https://doi.org/10.1016/s0065-2660(08)01001-8 [Accessed 1 Nov. 2023].
  2. Charles, B., et al (2013). Characterization of hyperkalemic periodic paralysis: a survey of genetically diagnosed individuals. Journal of Neurology, [online] 260(10), pp.2606–2613. Available at: https://doi.org/10.1007/s00415-013-7025-9   [Accessed 1 Nov. 2023].
  3. Statland, J., et al (2017). Review of the Diagnosis and Treatment of Periodic Paralysis. Muscle & Nerve, [online] 57(4), pp.522–530. Available at:: https://doi.org/10.1002/mus.26009 [Accessed 1 Nov. 2023].
  4. GOSH Hospital site. (2020). Sodium channel myotonia (paramyotonia congenita). [online] Available at: https://www.gosh.nhs.uk/conditions-and-treatments/conditions-we-treat/sodium-channel-myotonia-paramyotonia-congenita/ [Accessed 2 Jan. 2024].
  5. Muscular Dystrophy Association. (2017). Paramyotonia Congenita (Eulenberg Disease) – Diseases | Muscular Dystrophy Association. [online] Available at: https://www.mda.org/disease/paramyotonia-congenita [Accessed 2 Jan. 2024].
  6. National Organization for Rare Disorders. (2023). Paramyotonia Congenita. [online] Available at: https://rarediseases.org/rare-diseases/paramyotonia-congenita/#symptoms [Accessed 2 Jan. 2024].
  7. Venance, S.L., et al (2005). The primary periodic paralyses: diagnosis, pathogenesis and treatment. Brain, [online] 129(1), pp.8–17. Available at: https://doi.org/10.1093/brain/awh639 [Accessed 1 Nov. 2023].
  8. www.youtube.com (2023). 2023 PPA Conference: Anita Dharwadkar: Periodic Paralysis and Nutrition 005. [online] Available at: https://youtu.be/X6RWMp9sTJY [Accessed 30 Oct. 2023].
  9. Umar Farooque et al (2020). Primary Periodic Paralyses: A Review of Etiologies and Their Pathogeneses. Cureus. [online] Available at: https://doi.org/10.7759/cureus.10112 [Accessed 1 Nov. 2023].
  10. Channelopathy.nhs.uk. (2023). Dietary Advice For Channelopathies – Channelopathy Service. [online] Available at: https://channelopathy.nhs.uk/patients/living-channelopathies/dietary-advice/1178 [Accessed 2 Jan. 2024].‌
  11. National Organization for Rare Disorders. (2023). Paramyotonia Congenita. [online] Available at: https://rarediseases.org/rare-diseases/paramyotonia-congenita/#therapies [Accessed 2 Jan. 2024].

*Some areas of support may not be accessible to all patients. Eligibility criteria may apply to ensure compliance with all applicable federal and state requirements, and benefits may be limited to commercially insured patients only. For more detailed information about eligibility, terms and conditions, please contact the Cycle Vita team at +1 (888) 360-8482.