Valsartan Interactions

Valsartan is an angiotensin II receptor blocker that suppresses aldosterone, which slows the kidneys' excretion of potassium. The FDA-approved Diovan label warns that potassium supplements and potassium-containing salt substitutes may raise serum potassium to clinically significant levels, particularly in people with reduced kidney function, diabetes, or heart failure.

Spirulina has a modest blood-pressure-lowering effect in clinical trials and contributes a small amount of potassium. Combined with valsartan, the theoretical concerns are slightly additive blood pressure lowering and a minor contribution to potassium load. At usual supplement amounts neither effect is large, and for people with normal kidney function the combination is generally tolerable.