Does potassium in foods reduce effectiveness of bp meds

Hello Phyllis Homer,

Plenty of people have this concern!

Let me first tell you about what is in blood, as this helps explain the relationship between potassium and blood pressure.  Your blood is composed of red blood cells which carry oxygen from your lungs to your body; white blood cells which fight off infections; and the serum - the liquid component of blood - which carries waste products, hormones, salts, water, proteins, sugars, and tons and tons of other things.

Potassium is a component of the salts in your blood.  Several different BP medications work in the kidney by removing salts from your blood and putting them into urine (lasix and hydrochlorothiazide are diuretic medications).  When salts are put into urine, water from the serum follows.  By having less water in your blood vessels, the pressure in those vessels is reduced (i.e. lower blood pressure).

Potassium is also needed for the nerves to conduct signals from your brain to your muscles and for your muscles to contract.  By having too little potassium in your blood serum, your nerves can not conduct signals appropriately nor can your muscles relax appropriately; therefore you get cramps.

So, basically, the blood pressure medications you are on do deplete potassium in your body, and your doctor is replacing the potassium to keep you from getting cramps. 

The AARP booklet likely recommends avoiding these foods high in potassium and other salts because it can raise your blood pressure.  However, if your pressure is well controlled on the medications you take, you likely do not have to worry as much avoiding these foods. 

Hope this helps.

To your health,

Neil MD