Potassium

From Ganfyd

K. Element. Light metal. Essential to metabolism. Most of the K is intracellular, and therefore it is non-trivial to measure whole body content of Potassium. One approach is to count the photons with the energy characteristic of decay of ⁴⁰K. Frequently and importantly measured in plasma.

Hypokalaemia is common, particularly with use of diuretic drugs; hyperkalaemia is rare and alarmingly dangerous.

Rapid replacement of potassium is almost never necessary, and always hazardous. The main hazard is excessive dosage due to miscalculation and for this reason in Britain only preprepared dilutions are available on general hospital wards . It is always given diluted intravenously, typically no more than 40mmol/l of potassium per litre of fluid to prevent phlebitis

Usually administered as potassium chloride but the ion is quite common in medicines and this can be a source of unwanted, and even dangerous potassium in say renal failure.