Potassium Hypokalaemia

Hypokalaemia occurs when the plasma-potassium level falls below 3.0 mmol/L Hypokalaemia may occur following loop or thiazide diuretic therapy. Patients at risk of developing hypokalaemia are often prescribed potassium supplements to counteract the potassium loss caused by the diuretic therapy. Symptoms of hypokalaemia include muscle weakness and cramps. Severe cases may lead to muscle paralysis and respiratory failure. 

Ketanserin should not be combined with drugs that prolong the QT interval, e.g. class la anti-arrhythmics, amiodarone, sotalol, erythromycin. The risk of torsade de pointes secondary to hypokalaemia is increased when ketanserin is combined with thiazides or loop diuretics without concomitant use of a potassium-sparing diuretic or an angiotensin-converting enzyme (ACE) inhibitor, a 1 Antagonists... 

Her low potassium is probably a result of the diarrhoea, although note that corticosteroids can also cause hypokalaemia. Her low albumin suggests that she has had longer term malabsorption it is likely to take several weeks or longer to correct. 

AMIODARONE CARBONIC ANHYDRASE ANTAGONISTS, LOOP DIURETICS, THIAZIDES Risk of arrhythmias Cardiac toxicity directly related to hypokalaemia Monitor potassium levels eveiy 4-6 weeks until stable, then at least annually... 

MEXILETINE DIURETICS-CARBONIC ANHYDRASE INHIBITORS, LOOP DIURETICS, THIAZIDES Effect of mexiletine 1 by hypokalaemia Uncertain Normalize potassium levels before starting mexiletine... 

SOTALOL DIURETICS-CARBONIC ANHYDRASE INHIBITORS, LOOP DIURETICS, THIAZIDES t risk of ventricular arrhythmias, particularly torsades de pointes ventricular tachycardia, caused by sotalol Hypokalaemia, a side-effect of these diuretics, predisposes to arrhythmias during sotalol therapy Normalize potassium levels before starting sotalol in patients already taking these diuretics. When starting these diuretics in patients already taking sotalol, monitor potassium levels eveiy 4-6 weeks until stable... 

DIGOXIN CORTICOSTEROIDS Risk of digoxin toxicity due to hypokalaemia Corticosteroids may cause hypokalaemia Monitor potassium levels closely. Monitor digoxin levels watch for digoxin toxicity... 

CARBONIC ANHYDRASE INHIBITORS BRONCHODILATORS -BETA-2 AGONISTS, THEOPHYLLINE Risk of hypokalaemia Additive effects Monitor blood potassium levels prior to concomitant administration and during therapy. Administer potassium supplements to prevent hypokalaemia... 

CARBONIC ANHYDRASE INHIBITORS CARDIAC GLYCOSIDES Risk of digoxin toxicity t by acetazolamide due to hypokalaemia Uncertain Monitor potassium levels closely. Watch for digoxin toxicity and check levels... 

LOOP DIURETICS ANTI FUNG ALS -AMPHOTERICIN Risk of hypokalaemia Additive effect Monitor potassium closely... 

---