Situation: A public health nurse at a Rural Health Unit (RHU) in an agricultural municipality sees clients referred by the barangay health workers (BHWs). The client's hypertension is now treated with losartan. The nurse teaches her how to lower her salt intake. Which statement by the client shows that she needs **FURTHER** teaching?

Most salt substitutes contain potassium chloride. Combined with an angiotensin receptor blocker such as losartan, which raises serum potassium, they can cause dangerous hyperkalemia, so they should be used only if prescribed. The other statements are correct ways to reduce sodium: herbs and acid for flavor, keeping salt under about 5 g (one teaspoon) a day, and choosing fresh over preserved fish.

Core issue: Salt substitutes and losartan

The client is taking losartan, an angiotensin II receptor blocker (ARB). ARBs reduce aldosterone-mediated potassium excretion in the distal nephron, which means the kidneys retain more potassium. The teaching point here is not only about lowering sodium but also about avoiding an unintended rise in serum potassium.

A low-sodium diet is a well-established strategy to enhance the blood pressure–lowering effect of ARBs. In a randomized crossover study of hypertensive adults with type 2 diabetes, dietary sodium restriction potentiated the antihypertensive response to losartan, with the greatest blood pressure reduction occurring when losartan was combined with a low-sodium intake ^[1]. Sodium restriction is also emphasized as a core nonpharmacologic intervention in difficult-to-control hypertension, where excess dietary sodium directly opposes the action of antihypertensive agents ^[2][3]. These findings support the general advice to reduce salt intake while taking losartan.

The incorrect statement is option 4: “I will use a low-sodium salt substitute in place of regular salt.” Most commercially available low-sodium salt substitutes replace a portion of sodium chloride with potassium chloride. While potassium-enriched salt substitutes can lower blood pressure by reducing sodium and increasing potassium intake, their potassium content becomes a safety concern in patients whose potassium excretion is impaired ^[4]. Losartan raises serum potassium by blocking aldosterone effects, so adding a potassium-based salt substitute can produce hyperkalemia, a potentially life-threatening dysrhythmia risk. A salt substitute should be used only if specifically prescribed and monitored.

The other statements reflect appropriate sodium-reduction strategies. Using garlic, onion, and lemon juice replaces salt with non-sodium flavorings. Keeping total salt below about 5 g (one teaspoon) per day aligns with general sodium-restriction guidance. Choosing fresh fish over canned or dried fish avoids the high sodium content of preserved products.

Client statement	Safety with losartan	Rationale
Season food with garlic, onion, lemon juice	Safe	Adds flavor without sodium or potassium load
Keep total salt under one teaspoon daily	Safe	Supports sodium restriction and enhances ARB efficacy
Choose fresh fish instead of canned or dried fish	Safe	Avoids hidden sodium in preserved foods
Use a low-sodium salt substitute	Unsafe without prescription	Potassium chloride content can cause hyperkalemia with losartan

Watch out! A “low-sodium” label does not mean potassium-free. In a client taking an ARB, ACE inhibitor, or potassium-sparing diuretic, potassium-based salt substitutes are a common but serious source of iatrogenic hyperkalemia.

Key point! Sodium restriction is beneficial with losartan, but the method of sodium reduction must be potassium-neutral. The need for further teaching is identified when the client plans to use a potassium-containing salt substitute without a prescription.