While being treated with spironolactone, it is crucial to monitor and control your diet. Avoid eating foods that are high in salt, as excessive sodium works against this medication while causing your body to retain water. It is also important to avoid potassium supplements or foods high in potassium, such as low-sodium milk products or those containing salt substitutes. Spironolactone increases potassium levels and supplemental potassium may raise the levels too high. Avoid becoming dehydrated during spironolactone treatment, as the balance of fluid in the body must be upheld for this medicine to be effective. It is important to note that drinking too much as well as too little fluids can be equally dangerous while taking spironolactone. Your doctor can recommend a healthy amount of fluid to drink during treatment.