Electrolyte disorders   

Would you check an aldosterone to renin ratio in the setting of hypokalemia, knowing that the result will be impacted by the potassium level?

Seethapathy et al., PMID 38320180

For a patient whose sodium remains 142 despite water deprivation from 8 pm to 8 am, with urine osm of about 500, is further testing needed?

Or other therapy - e.g., tolvaptan? Free water restriction may hinder QOL. Salt tablets may raise levels more quickly but have risks of edema and hype...