Blood pressure that stays above 140/90 mm Hg despite the use of three antihypertensive medications, including a diuretic, is known as resistant hypertension.

About 1.28 billion adults around the world have high blood pressure (hypertension), and the condition is well managed in only about 1 in 5 people who have it. Ongoing hypertension increases the risk of heart attack, stroke, and kidney problems.

For some people, even the use of multiple medications may not be enough to lower blood pressure. When high blood pressure persists despite the use of medications, it may be classified as resistant hypertension.

If you or someone you know has hypertension that is continuing despite treatment, you might consider consulting your doctor to find out the best next steps.

Research suggests that about 10% of people in Western countries who have high blood pressure have resistant hypertension.

Resistant hypertension is high blood pressure that stays above 140/90 millimeters of mercury (mm Hg) even when you take three hypertension-related medications, including a diuretic, at the highest tolerable doses for 6 months.

Much of the difference between resistant, refractory, and uncontrolled hypertension has to do with how medications are used (or not used) to try to treat high blood pressure:

  • Uncontrolled hypertension is a type of high blood pressure above 140/90 mm Hg. If you have uncontrolled hypertension, you may not be receiving treatment for it, or your condition may be unresponsive to treatment. You can read more about uncontrolled hypertension here.
  • Refractory hypertension is a type of high blood pressure that remains uncontrolled even when you take at least five hypertension-related medications at the highest tolerable doses to try to treat it. You can read more about refractory hypertension here.

Hypertension can be due to primary or secondary causes. Primary causes of hypertension include aging and lifestyle factors. Secondary causes of hypertension include various medications and medical conditions that raise blood pressure.

It’s possible to experience hypertension with both primary and secondary causes. Additional primary and secondary factors can occur over time, causing hypertension to become uncontrolled or elevated to the point that it meets the definition of other types of hypertension.

Some cases of resistant hypertension are related to medical conditions and medications. Examples of medical conditions that can lead to resistant hypertension are:

Most resistant hypertension cases have unknown causes. They are likely the result of multiple factors, including:

  • genetics
  • smoking
  • excessive consumption of alcohol or foods high in salt
  • obesity
  • sedentary lifestyle

There are also cases of “pseudo-resistant” hypertension. This means that you might seem to have resistant hypertension, but other factors are actually affecting that diagnosis.

For example, if you’re not taking your blood pressure medications according to your doctor’s instructions, it may seem as if your blood pressure is not responding to medications. If you don’t take medications in the proper doses and at the proper times, the medications may be less effective, leading to apparent resistant hypertension.

Additionally, if a healthcare professional does not take your blood pressure properly, an inaccurate reading can make it appear that you have resistant hypertension even if you do not.

There are also times when your blood pressure might read higher than it usually does. One example of this is white coat hypertension in the doctor’s office. You can learn more about that here.

While many people with hypertension do not experience symptoms, the possible symptoms of hypertension include:

  • headaches
  • chest pain
  • abnormal heart rhythms
  • anxiety and confusion
  • dizziness
  • vomiting and nausea
  • difficulty breathing
  • nosebleeds
  • vision changes
  • buzzing in your ears

Research supports the use of spironolactone as a fourth medication for resistant hypertension.

If you have a negative reaction to spironolactone or there’s another reason not to use it, your doctor may recommend amiloride, doxazosin, bisoprolol, or clonidine as an alternative.

In addition to prescribing more medications, doctors may address resistant hypertension by:

  • recommending a diet with less salt and alcohol
  • encouraging physical activity
  • offering advice on maintaining a healthy weight
  • checking that you are taking hypertension medications properly
  • investigating and treating any related health conditions, such as kidney disease, sleep apnea, and irregular hormone levels

Resistant hypertension is high blood pressure that stays above 140/90 mm Hg even when you’re taking at least three medications meant to lower it, including a diuretic. This may be due to other medical conditions or incorrect use of the medications.

If you’re experiencing resistant hypertension, it’s important to make sure you’re taking all prescribed medications appropriately, making any lifestyle changes your doctor recommends, and discussing with your doctor whether additional medications, such as spironolactone, are necessary.