Chart Comparing Periodic Paralyses
This chart allows comparison of the forms of primary periodic paralysis, symptoms, clinical and cardiac signs, effect of potassium, triggers and therapies.
| Form | Effect of K+ | Age at onset | Triggers | Relieves | Attack Length | Myotonia? | Hypertrophy | Weakness between attacks | EKG during attacks | Therapies |
|---|---|---|---|---|---|---|---|---|---|---|
| Thyrotoxic HypoKalemic Periodic Paralysis | Relieves weakness | At any age, 85% males; usually in 20–40 year–old Asians, Native Americans | Hyperthyroidism (may be sub–clinical) ^ carbohydrate meal and exertion. | K+, Treat thyroid condition | Hours to days | No | No | Yes | During attacks ST depression, T wave flattens, U wave appears, sinus tachycardia | Methimazole, Propranolol, K+, until anti–thyroid treatment, radio-iodine 131 or surgery |
|
Hypokalemic Periodic Paralysis |
Relieves weakness | 1-25 years | simple carbs, rest after exertion, sleep, strong emotion | K+, mild exercise | 1-72 hours | only in eyelids | Yes | Yes, after age 35 | ST depression, T flattens, U rises | Diamox, K+, K+ sparing diuretics |
| Andersen-Tawil Syndrome | Provokes weakness while relieving arrhythmia and/or weakness in some patients. | At any age | Varies from patient to patient, exercise, sleep, high K+ in some, low K+ in others. | Varies from patient to patient. | Varies | No | No | Yes | LQTc, ectopy, bigeminy, tachycardia, (in or out of attack) | Varies, usually beta blockers + treatment for weakness |
| Hyperkalemic Periodic Paralysis | Provokes weakness | First decade | Hunger, K+ in foods, rest after exercise, immobility | Sugar, mild exercise | 5 min – 12 hours | In grip and exercised muscles | Yes | Yes | T tall “tented”, R falls, QRS/PR increases, P gone | K+ wasting diuretics, Diamox, Albuterol |
| Paramyotonia Congenita (Pure form) | Provokes weakness | First two years | Exercise, K+ | Sugar, rest | Minutes – days | Face, eyes, jaw, hands. | Worsens with cold and activity | Yes | May show signs of Hyperkalemia | K+ wasting diuretics, Paxil, Mexiletine |
| Paramyotonia Congenita von Eulenburg | Relieves weakness | First two years | Exercise, LOW K+ | K+ rest | Minutes – weeks | May be absent at room temp. | Yes | Yes | May show signs of hypokalemia | Mexiletine, Paxil, K+ |
| Acetazolamide– responsive Paramyotonia Congenita | Provokes pain and stiffness, No weakness | ? | K+, activity | Diamox | ? | Worse with Activity | Yes | ? | ? | Diamox |
| Myotonia Fluctuans | Provokes stiffness, NO weakness | K+ | ? | Mild, Varies | ? | Diamox, K+ wasting diuretics | ||||
| Myotonia Permanens | Provokes severe myotonia | ? | K+ | ? | Constant | Severe, continuous | Marked | ? | ? | Diamox, K+ wasting diuretics |
