Pragmatic diagnostic algorithm for hypokalemia. 

***Typical presentations: 

 • Vomiting: urine Na/Cl > 1.6, low urine Cl; 

 • Laxative: urine Na/Cl < 0.7, high urine Cl; 

 • Active diuretic use: similar to tubulopathy; 

 • Tubulopathy: urine K/creatinine (Cr) > 2.5 mmol/mmol, with urine Na/Cl ~1. Tubulopathy may be confirmed via genetic testing

*If hypokalemia seems disproportionately severe to the dose of diuretic,

one may still consider aldosterone excess. 

**Ideally, after correcting serum potassium levels, with the patient not taking mineralocorticoid

receptor antagonists. Other medications, including angiotensin-converting enzyme inhibitors and angiotensin receptor blockers, may be continued in most cases; interpretation is dependent upon local laboratory methods and reporting.137,138 



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