Management of Hypokalemic Periodic Paralysis
Oral potassium chloride is the first-line treatment for acute attacks of hypokalemic periodic paralysis, with carbonic anhydrase inhibitors (acetazolamide or dichlorphenamide) serving as the mainstay of long-term prophylaxis. 1, 2, 3
Acute Attack Management
Initial Assessment and Potassium Replacement
- Administer oral potassium chloride immediately for acute weakness episodes, as this is typically sufficient for most patients 2, 4
- For patients requiring intravenous potassium (severe weakness, inability to take oral medications), use potassium chloride in mannitol or saline—never in glucose-containing solutions, as glucose worsens weakness and prevents potassium rise 4
- IV potassium dosing should not exceed 10 mEq/hour or 200 mEq per 24 hours when serum potassium is >2.5 mEq/L 5
- In severe cases with serum potassium <2 mEq/L and ECG changes or muscle paralysis, rates up to 40 mEq/hour can be administered with continuous ECG monitoring 5
Critical Pitfall: Glucose Administration
- Avoid all glucose-containing IV solutions during acute attacks, as glucose provokes further weakness and prevents potassium correction 4, 6
- This includes avoiding high-carbohydrate meals, which are known triggers for attacks 3
Long-Term Prophylactic Management
First-Line Prophylaxis
- Carbonic anhydrase inhibitors are the primary preventive therapy 1, 3
- Dichlorphenamide or acetazolamide should be initiated for patients with recurrent attacks 3
- Acetazolamide may paradoxically worsen attacks in some patients due to its potassium-lowering effect 6
Alternative Prophylactic Agents
- Triamterene (potassium-sparing diuretic) is effective for patients who worsen on acetazolamide, as it increases serum potassium levels and prevents attacks 6
- Topiramate, which has carbonic anhydrase inhibitory properties, may reduce attack severity and warrants consideration 7
Monitoring and Follow-Up
Nephrology Involvement
- Regular nephrology follow-up is essential due to the risk of developing progressive proximal myopathy as a long-term complication 3
- Nephrologists play a crucial role in both diagnosis and ongoing management of this condition 3
Trigger Avoidance
- Counsel patients to avoid prolonged rest following exercise 3
- Avoid high-carbohydrate meals 3
- Avoid glucose-containing IV solutions during any medical treatment 4
Special Considerations
Distinguishing from Hyperkalemic Periodic Paralysis
- Unlike hyperkalemic periodic paralysis, hypokalemic periodic paralysis requires potassium supplementation rather than potassium-lowering measures 1, 2
- The FDA label specifically indicates potassium chloride for "patients with hypokalemic familial periodic paralysis" 2