簡單地報一個case，data很多忘記懶得查，敬請見諒6359406
86歲的龔先生是個老菸槍，有高血壓，慢性咳嗽的問題，這兩年來常服用Brown mixture與國安感冒糖漿。他這兩年逐漸有下肢無力的現象，跌倒過數次，最近發現上肢有時也會無力，另外他也提到最近容易口渴，喝比較多水。入院兩天前甚至脖子發軟，無法抬頭，且有頭暈現象，因此被送入急診。
EKG: sinus rhythm, QT prolong, CK:40000, K:2, normal range of CBC/DC, liver, renal function,
ABG: metabolic alkalosis, TTKG>10
normal cortisol, thyroid function, normal renin, aldosterone level
鉀離子補回正常值後，一切症狀消失，出院
Dx: Hypokalemia c/w rhabdomyolysis, favor licorice related
Discussion:
B.M.和感冒糖漿中的止咳成分：Licorice含有甘草酸Glycyrrhizin，會作用在11-beta hydroxysteroid dehydrogenase ，此酵素能把active cortisol 轉換為inactive cortisone，然而過量服用licorice 的患者，會有pseudohyper-minerocorticoid 的狀況，cortisol相對較多，繼續合成為Glucocorticoid, minerocorticoid，而有留鈉排鉀的效果。
病人常見progressive paralysis，從下肢慢慢延伸，又，低血鉀可能造成橫紋肌溶解症。
In addition, rhabdomyolysis can develop as a result of potassium depletion. Potassium release from muscle cells during exertion normally mediates blood flow to muscles during exercise. Decreased potassium release causes less blood flow to the muscles. This decreased blood flow can lead to rhabdomyolysis and the associated cascade of metabolic problems.
要小心的有
1. Potassium levels below 3.0 mEq/L (3.0 mmol/L) are associated with a 2-fold increase in ventricular dysrhythmia.
2. Patients with hypokalemia almost always have coincident hypomagnesemia and should be treated empirically with magnesium repletion. Until the magnesium deficit is corrected, potassium will not return to normal levels despite the administration of appropriate potassium.
