Hypokalemic periodic paralysis

- autosomal dominant
- mutation in muscle voltage gated calcium channel gene (CACLN1A3)
- associated with thyrotoxicosis
- commonly caused by medication (diuretics)
- can occur with hyperkalemia, but less common
- generalised weakness, including bulbar muscles, often starts after a heavy carbohydrate meal or following exertion
- potassium should be given before bicarbonate as bicarbonate can precipitate further hypokalemia