High blood pressure

High blood pressure is a condition that puts you at risk for heart attack, stroke, and kidney disease. It does not usually cause symptoms. But it can be serious.

When your doctor or nurse tells you your blood pressure, they will say 2 numbers. For instance, your doctor or nurse might say that your blood pressure is “130 over 80.” The top number is the pressure inside your arteries when your heart is contracting. The bottom number is the pressure inside your arteries when your heart is relaxed.

Hypertension is a common health problem. In the United States, approximately 46 percent of adults have hypertension.

Hypertension is more common as people grow older. In the United States, for example, it affects 76 percent of adults aged 65 to 74 years and 82 percent of adults aged 75 years or older.

Unfortunately, many people’s blood pressure is not well controlled. According to a national survey, hypertension was under good control in only 47 percent of adults.

“Elevated blood pressure” is a term doctors or nurses use as a warning. People with elevated blood pressure do not yet have high blood pressure. But their blood pressure is not as low as it should be for good health.

Many experts define high, elevated, and normal blood pressure as follows:

  • High– Top number of 130 or above and/or bottom number of 80 or above
  • Elevated– Top number between 120 and 129 and bottom number of 79 or below
  • Normal– Top number of 119 or below and bottom number of 79 or below

If your doctor or nurse has prescribed blood pressure medicine, the most important thing you can do is to take it. If it causes side effects, do not just stop taking it. Instead, talk to your doctor or nurse about the problems it causes. They might be able to lower your dose or switch you to another medicine. If cost is a problem, mention that too. They might be able to put you on a less expensive medicine. Taking your blood pressure medicine can keep you from having a heart attack or stroke, and it can save your life!

Can I do anything on my own?

You have a lot of control over your blood pressure. To lower it:

  • Lose weight (if you are overweight)
  • Choose a diet low in fat and rich in fruits, vegetables, and low-fat dairy products
  • Reduce the amount of salt you eat
  • Do something active for at least 30 minutes a day on most days of the week
  • Cut down on alcohol (if you drink more than 2 alcoholic drinks per day)

It’s also a good idea to get a home blood pressure meter. People who check their own blood pressure at home do better at keeping it low and can sometimes even reduce the amount of medicine they take.

Making changes to what you eat can help control high blood pressure.

Reduce sodium (salt) — Reducing the amount of sodium you consume can lower blood pressure if you have hypertension or elevated blood pressure.

The main source of sodium in the diet does not come from the salt shaker; it comes from the salt contained in packaged and processed foods and in foods from restaurants.

The body requires a small amount of sodium in the diet, and most people consume more sodium than they need (over 3 grams per day). A low-sodium diet contains fewer than 2.4 grams (2400 milligrams) of sodium per day. Although the ideal target for daily sodium intake remains controversial, the optimal goal is less than 1500 mg per day.

Many people think that eating a low-sodium diet means avoiding the salt shaker and not adding salt when cooking. The truth is, not adding salt at the table or when you cook will only help a little. Almost all of the sodium you eat is already in the food you buy at the grocery store or at restaurants.

The most important thing you can do to cut down on sodium is to eat less processed food. That means that you should avoid most foods that are sold in cans, boxes, jars, and bags. You should also eat in restaurants less often.

To reduce the amount of sodium you get, buy fresh or fresh-frozen fruits, vegetables, and meats. (Fresh-frozen foods have had nothing added to them before freezing.) Then you can make meals at home, from scratch, with these ingredients.

As with the other changes, don’t try to cut out salt all at once. Instead, choose 1 or 2 foods that have a lot of sodium and try to replace them with low-sodium choices. When you get used to those low-sodium options, find another food or 2 to change. Then keep going, until all the foods you eat are sodium-free or low in sodium.

Reduce alcohol — Drinking a lot of alcohol increases your risk of developing high blood pressure. A “drink” is defined as 5 oz of wine, 12 oz of beer, or 1 oz of hard liquor. Drinking more than two drinks per day increases the risk of high blood pressure compared with not drinking, and it also makes hypertension more difficult to control. Binge drinking (consuming four to five drinks within two hours) is an even greater problem for overall health and hypertension.

Eat more fruits and vegetables — Adding more fruits and vegetables to your diet may reduce high blood pressure or protect against developing high blood pressure; it can also help improve your health in general.

Eat more fiber — Eating an increased amount of fiber may decrease blood pressure. The recommended amount of dietary fiber is 20 to 35 grams of fiber per day. Many breakfast cereals are excellent sources of dietary fiber. More information about increasing fiber is available separately

Caffeine — Caffeine can temporarily increase blood pressure in people who don’t consume it regularly. In regular caffeine users, a moderate amount of caffeine (equivalent to approximately two cups of coffee daily) usually does not affect blood pressure. However, excessive amounts of caffeine (such as in many supplements and large-size beverages) may raise blood pressure in susceptible people.

Dietary Approaches to Stop Hypertension (DASH) eating plan — The DASH eating plan combines many of the dietary interventions noted above. It is high in fruits, vegetables, whole grains, fiber, and low-fat dairy products, with reduced saturated fat, total fat, and meat intake. All people, including those with and without high blood pressure, who strictly follow the DASH eating plan can have fairly significant reductions in blood pressure, particularly when combined with a low-sodium diet.

Exercise — Regular exercise can lower your blood pressure even if you don’t lose weight. Recommendations from the American Heart Association suggest that to achieve substantial health benefits requires 150 to 300 minutes per week of moderate-intensity aerobic activity (such as brisk walking) or 75 to 150 minutes per week of vigorous intensity aerobic activity (such as jogging) plus muscle-strengthening exercises (resistance training) involving all major muscle groups at least twice per week . Isometric exercises (eg, repeated handgrip contraction) may also be of benefit. Exercise will not only help lower blood pressure but also improves cholesterol levels. However, to maintain this benefit, you must continue to exercise regularly. Although this level of exercise is recommended to get substantial reductions in blood pressure (4 to 5 mmHg systolic), any amount of physical activity is better than none. Even gentle forms of exercise, like walking, have health benefits.

Weight Loss and Blood Pressure —Being overweight or having obesity increases your risk of having high blood pressure, diabetes, and cardiovascular disease. The definition of overweight and obese are based upon a calculation called body mass index (BMI). You can find your BMI using an online calculator. A person is considered overweight if their BMI is greater than 25, while a person with a BMI of 30 or greater is classified as having obesity. People who are overweight or have obesity can see significant reductions in blood pressure with even modest weight loss.

To lose weight, you must eat fewer calories and exercise more

Avoid Medications and Supplements that increase Blood Pressure — In susceptible individuals, nonsteroidal anti-inflammatory drugs or “NSAIDs” (such as ibuprofen and naproxen) can increase blood pressure. Oral contraceptive (birth control) pills may increase blood pressure in some people. Additionally, any stimulant, including those found in some decongestants, weight loss products, and illegal drugs, can increase blood pressure. If you are regularly consuming any of these substances, you should talk to your health care provider.

Blood pressure is usually measured with a device that goes around your upper arm. This is often done in a doctor’s office. But some people also check their blood pressure themselves, at home or at work.

Blood pressure is explained with 2 numbers. For instance, your blood pressure might be “140 over 90.” The first (top) number is the pressure inside your arteries when your heart is contracting. The second (bottom) number is the pressure inside your arteries when your heart is relaxed. The table shows how doctors and nurses define high and normal blood pressure (table 1).

If your blood pressure gets too high, it puts you at risk for heart attack, stroke, and kidney disease. High blood pressure does not usually cause symptoms. But it can be serious.

A home blood pressure meter (or “monitor”) is a device you can use to check your blood pressure yourself. It has a cuff that goes around your upper arm (figure 1). Some devices have a cuff that goes around your wrist instead. But doctors aren’t sure if these work as well. The meter also has a small screen, or dial, that shows your blood pressure numbers.

There are also special meters you can wear for a day or 2. These are different because they automatically check your blood pressure throughout the day and night, even while you are sleeping. If your doctor thinks you should use one of these devices, they will talk to you about how to wear it.

If your doctor knows or suspects that you have high blood pressure, they might want you to check it at home. There are a few reasons for this. Your doctor might want to look at:

  • Whether your blood pressure measures the same at home as it did in the doctor’s office
  • How well your blood pressure medicines are working
  • Changes in your blood pressure, for example, if it goes up and down

People who check their own blood pressure at home usually do better at keeping it low.

When choosing a home blood pressure meter, you will probably want to think about:

  • Cost – Some devices cost more than others. You should also check to see if your insurance will help pay for your device.
  • Size – It’s important to make sure the cuff fits your arm comfortably. Your doctor or nurse can help you with this.
  • How easy it is to use – You should make sure you understand how to use the device. You also need to be able to read the numbers on the screen.

You do not need a prescription to buy a home blood pressure meter. You can buy them at most pharmacies or over the internet. Your doctor or nurse can help you choose the right device for you.

Once you have a home blood pressure meter, your doctor or nurse should check it to make sure it fits you and works correctly.

When it’s time to check your blood pressure:

  • Go to the bathroom and empty your bladder first. Having a full bladder can temporarily increase your blood pressure, making the results inaccurate.
  • Sit in a chair with your feet flat on the ground.
  • Try to breathe normally and stay calm.
  • Attach the cuff to your arm. Place the cuff directly on your skin, not over your clothing. The cuff should be tight enough to not slip down, but not uncomfortably tight.
  • Sit and relax for about 3 to 5 minutes with the cuff on.
  • Follow the directions that came with your device to start measuring your blood pressure. This might involve squeezing the bulb at the end of the tube to inflate the cuff (fill it with air). With some monitors, you just need to press a button to inflate the cuff. When the cuff fills with air, it feels like someone is squeezing your arm, but it should not hurt. Then you will slowly deflate the cuff (let the air out of it), or it will deflate by itself. The screen or dial will show your blood pressure numbers.
  • Stay seated and relax for 1 minute, then measure your blood pressure again.

How often should I check my blood pressure?
It depends. Different people need to follow different schedules. Your doctor or nurse will tell you how often to check your blood pressure, and when. Some people need to check their blood pressure twice a day, in the morning and evening.

Your doctor or nurse will probably tell you to keep track of your blood pressure for at least a few days (table 2). Then they will look at the numbers. The reason for this is that it’s normal for your blood pressure to change a bit from day to day. For example, the numbers might change depending on whether you recently had caffeine, just exercised, or feel stressed. Checking your blood pressure over several days – or longer – will give your doctor or nurse a better idea of what is average for you.

Some blood pressure meters will record your numbers for you, or send them to your computer or smartphone. If yours does not do this, you will need to write them down. Your doctor or nurse can help you figure out the best way to keep track of the numbers.

Your doctor or nurse will tell you what to do if your blood pressure is high when you check it at home. If you get a number that is higher than normal, measure it again to see if it is still high. If it is very high (above a certain number, which your doctor or nurse will tell you to watch out for), you should call your doctor right away.

If your blood pressure is only a little high, your doctor or nurse might tell you to keep checking it for a few more days or weeks, and then call if it does not go back down. Then they can help you decide what to do next.

Having high blood pressure puts you at risk for heart attack, stroke, kidney damage, and other serious problems. The medicines your doctor or nurse prescribes to treat high blood pressure can help reduce the risk of these problems and even help you live longer.

It’s very important that you take your blood pressure medicines every day as directed. High blood pressure doesn’t usually cause symptoms, so people sometimes don’t take it seriously. Plus, blood pressure medicines can cause side effects and be expensive, so it’s easy to understand why people don’t like to take them. But if you are tempted to skip your medicines, remember, they can save your life!

If your medicines cause unpleasant side effects, or if you can’t afford your medicines, talk to your doctor or nurse. There are often ways to deal with these problems. The first step is to let your doctor or nurse know.

Here are various medications that are commonly used to treat high blood pressure.

Some people will respond well to one drug but not to another. Therefore, it may take time to determine the right drug(s) and proper dose to effectively lower blood pressure with a minimum of side effects.

Although generally well tolerated, high blood pressure medications can cause side effects; the side effects depend upon the specific drug given, dose, and other factors. Some side effects result from lowering of the blood pressure, usually if the blood pressure lowering is abrupt, and therefore can be caused by any high blood pressure medication. These include dizziness, drowsiness, lightheadedness, or feeling tired. They usually subside after a few weeks when the body has adapted to the lower blood pressure.

Diuretics — Diuretics lower blood pressure mainly by causing the kidneys to excrete more sodium and water, which reduces fluid volume throughout the body and widens (dilates) blood vessels.

The diuretics used to treat high blood pressure are thiazides (chlorthalidone, hydrochlorothiazide, and indapamide). In some cases, a potassium supplement or a potassium-sparing diuretic (amiloride, spironolactone, or triamterene) are given in combination with a thiazide diuretic because the thiazides can cause potassium deficiency since increased amounts of potassium are excreted in the urine. Thiazide diuretics also cause a decrease in urinary calcium excretion, meaning that more calcium stays in the body. Because of this, they may be the preferred treatment for people with high blood pressure and osteoporosis (a common problem that causes weakening and thinning of the bones).

Side effects — Side effects are uncommon with low doses of thiazide diuretics. Weakness, muscle cramps, and other symptoms can occur as a result of decreased sodium, potassium, and water level. Other symptoms may include reversible erectile dysfunction and gout attacks.

ACE inhibitors — Angiotensin-converting enzyme (ACE) inhibitors block production of the hormone, angiotensin II, a compound in the blood that causes narrowing of blood vessels and increases blood pressure. By reducing production of angiotensin II, ACE inhibitors allow blood vessels to widen, which lowers blood pressure and improves heart output.

The available ACE inhibitors include benazepril, captopril, enalapril, fosinopril, lisinopril, moexipril, perindopril, quinapril, ramipril, and trandolapril.

Side effects — In some people, ACE inhibitors cause a persistent dry cough that is reversible when the medication is stopped. Less common side effects include dry mouth, nausea, rash, muscle pain, or, occasionally, kidney dysfunction and elevated blood potassium.

A potentially serious complication of ACE inhibitors is angioedema, which occurs in 0.1 to 0.7 percent of people. This can develop minutes to hours after taking the medication, although it sometimes takes longer. People with angioedema have swelling of the lips, tongue, and throat, which can interfere with breathing. These symptoms are a medical emergency, and the ACE inhibitor should be discontinued.

Angiotensin II receptor blockers — The angiotensin II receptor blockers (ARBs) block the effects of angiotensin II on cells in the heart and blood vessels. Similar to ACE inhibitors, ARBs can widen blood vessels, lower blood pressure, and improve heart output.

The available ARBs include azilsartan, candesartan, irbesartan, losartan, olmesartan, telmisartan, and valsartan.

Side effects — The main difference between ARBs and ACE inhibitors is that ARBs do not produce cough. Some people who take ARBs experience headache, nausea, dry mouth, abdominal pain, or other side effects. Angioedema is less common with ARBs than with ACE inhibitors.

Calcium channel blockers — Calcium channel blocker drugs reduce the amount of calcium that enters the smooth muscle in blood vessel walls and heart muscle. Muscle cells require calcium to contract. Thus, by inhibiting the flow of calcium across muscle cell membranes, calcium channel blockers cause muscle cells to relax and blood vessels to dilate, reducing blood pressure as well as reducing the force and rate of the heartbeat.

There are two major categories of calcium channel blockers:

  • Dihydropyridines, including amlodipine, felodipine, isradipine, nicardipine, nifedipine, and nisoldipine
  • Nondihydropyridines, including diltiazem and verapamil

Side effects — The side effects of calcium channel blockers vary with the specific agent used. People who take dihydropyridine calcium channel blockers may develop headache, flushing, nausea, overgrowth of the gum tissue (gingival hyperplasia), or swelling of the extremities (peripheral edema).

Nondihydropyridine calcium channel blockers can occasionally cause the heart rate to slow too much. Other side effects may include headache and nausea with diltiazem or constipation with verapamil.

Beta blockers — Beta blockers block some of the effects of the sympathetic nervous system, which increases the heart rate and raises blood pressure with stress and/or activity. Beta blockers lower blood pressure in part by decreasing the rate and force at which the heart pumps blood.

The available beta blockers include acebutolol, atenolol, betaxolol, bisoprolol, metoprolol, nadolol, nebivolol, pindolol, propranolol, and timolol.

Some beta blockers have combined activity, blocking both the beta and alpha receptors (see next section). These include labetalol and carvedilol.

Side effects — Beta blockers may worsen symptoms of asthma, other lung diseases, or blood vessel disease outside the heart (such as peripheral vascular disease). As a result, they normally are not prescribed for people with such conditions.

In addition, beta blockers may mask symptoms of low blood sugar (hypoglycemia) in people with diabetes who are treated with insulin. Beta blockers can also cause fatigue, insomnia, strange dreams, a decreased ability to exercise, a slow heart rate, rash, and cold hands and feet due to reduced blood flow to the limbs.

Alpha blockers — Alpha blockers relax or reduce the tone of involuntary (ie, smooth) muscle in the walls of blood vessels (vascular smooth muscle), allowing the vessels to widen, thereby lowering blood pressure. An increase in blood vessel diameter is known as “vasodilation.” The available alpha blockers include doxazosin, prazosin, and terazosin.

Side effects — Alpha blockers can cause dizziness, particularly when standing up, and particularly with the first few doses, low blood pressure when standing, or other side effects. They also may increase the risk of developing heart failure. For these reasons, they are not frequently used as a first-line treatment of primary hypertension (formerly called “essential” hypertension). A possible exception is in an older male with symptoms related to enlargement of the prostate; such symptoms may be relieved by alpha blocker therapy

Direct vasodilators — Direct vasodilators relax or reduce the tone of blood vessels. The two drugs in this class are hydralazine and minoxidil. Minoxidil is typically used in only severe or resistant high blood pressure.

Side effects — Side effects associated with direct vasodilators include headache, constipation, swelling in the lower legs, and rapid heartbeat. These effects are usually minimized by combining the vasodilator with a beta blocker.

Minoxidil also may cause excess hair growth. (Topical forms of minoxidil [sample brand name: Rogaine] are used as a treatment for hair loss.)

Are there any medicines I should avoid? Some medicines can “interact” with other medicines. Taking certain medicines can change how your blood pressure medicines work or make them work less well. Your doctor or nurse will talk to you about whether you need to avoid certain prescription or over-the-counter medicines, herbs, or supplements. If you have any questions about whether it is safe to take a medicine, ask your doctor, nurse, or pharmacist.

Renovascular hypertension

Renovascular hypertension is a type of high blood pressure. It happens when the renal arteries, the blood vessels that carry blood to the kidneys, become narrow.

High blood pressure puts you at risk for heart attack, stroke, and kidney disease. It does not usually cause symptoms. But it can be serious.

When your doctor or nurse tells you your blood pressure, they will say 2 numbers. For instance, your doctor or nurse might say that your blood pressure is “140 over 90.” The top number is the pressure inside your arteries when your heart is contracting. The bottom number is the pressure inside your arteries when your heart is relaxed.

This table shows how doctors and nurses define high and normal blood pressure.

Renovascular hypertension is sometimes called “renal artery stenosis.”

Maybe. If you have renovascular hypertension, your doctor might be able to hear a “whooshing” sound when listening to your belly through a stethoscope.

The doctor can also order imaging tests that create pictures of the renal arteries. But these tests are only done if the doctor thinks a procedure to open up the arteries could be helpful.

See your doctor or nurse right away if you have high blood pressure and get any of the following symptoms:

  • A very bad headache
  • Chest pain
  • Severe pain in your upper back
  • Problems breathing
  • Weakness on 1 side of your body and not the other
  • Problems speaking
  • Nausea or vomiting
  • Confusion
  • Vision changes
  • Blood in your urine

These can be signs of a very serious type of high blood pressure that needs to be treated as soon as possible.

Treatments include medicines for high blood pressure, such as:

  • ACE inhibitors and ARBs – ACE inhibitors and ARBs are often grouped together, because they work in similar ways. These medicines can help prevent kidney disease.

Some examples of ACE inhibitors include enalapril, captopril, and lisinopril. Some examples of ARBs include candesartan (brand name: Atacand) and valsartan (brand name: Diovan).

  • Diuretics – Some examples of diuretics include chlorthalidone, hydrochlorothiazide (also known as HCTZ), and furosemide (brand name: Lasix).
  • Calcium channel blockers – Some examples of calcium channel blockers include amlodipine (brand name: Norvasc), felodipine (brand name: Plendil), and diltiazem (brand name: Cardizem). These medicines also help prevent chest pain caused by heart disease.
  • Beta blockers – Some examples of beta blockers include atenolol (brand name: Tenormin), metoprolol (brand names: Lopressor, Toprol-XL), and propranolol (brand name: Inderal LA).

This article has only some basic information on these medicines. For more detailed information about your medicines, ask your doctor or nurse for the patient hand-out from Lexicomp, available through UpToDate. It explains how to use each medicine, describes its possible side effects, and lists other medicines or foods that can affect how it works.

Your doctor might recommend a procedure called “angioplasty” to open up 1 (or possibly both) of your renal arteries. During an angioplasty, the doctor puts a thin tube into a blood vessel in the leg and advances the tube to the kidney. Then the doctor inflates a tiny balloon inside the clogged artery to reopen it. Often the doctor props open the artery using a tiny mesh tube called a stent. Doctors only recommend angioplasty in certain situations.

You can reduce your chances of getting renovascular hypertension by keeping your blood vessels healthy. To do that, you should:

  • Quit smoking, if you smoke.
  • Walk, or do some form of physical activity on most days of the week.
  • Lose weight, if you are overweight.

A high blood pressure emergency is a serious – and even life-threatening – condition that can happen when a person’s blood pressure gets much higher than normal. When a person’s blood pressure gets very high, it can lead to problems in one or more of the following organs:

  • Eyes – Problems can include bleeding in the back of the eye, or swelling of the nerve that runs from the eye to the brain.
  • Brain – Problems can include swelling or bleeding in the brain, or a stroke. A stroke is when a part of the brain is damaged because of a problem with blood flow.
  • Kidneys – Very high blood pressure can lead to kidney failure, which is when the kidneys stop working.
  • Heart – Heart problems can include a heart attack, heart failure, or damage to a major blood vessel.

When your doctor or nurse tells you your blood pressure, they say 2 numbers. For example, your doctor might say that your blood pressure is “140 over 90.” When people have a high blood pressure emergency, their blood pressure is usually “180 over 120” or higher.

Other terms doctors might use for a high blood pressure emergency are “hypertensive emergency” or “malignant hypertension.”

Sometimes, a person’s blood pressure is much higher than normal, but it hasn’t damaged any organs. Doctors call this “hypertensive urgency.” Hypertensive urgency is not usually treated the same as a high blood pressure emergency.

High blood pressure emergencies

The symptoms depend on the organ or organs affected. They can include:

  • Blurry vision or other vision changes
  • Headache
  • Nausea or vomiting
  • Confusion
  • Passing out or seizures – Seizures are waves of abnormal electrical activity in the brain that can make people move or behave strangely.
  • Weakness or numbness on one side of the body, or in one arm or leg
  • Difficulty talking
  • Trouble breathing
  • Chest pain
  • Pain in the upper back or between the shoulders
  • Urine that is brown or bloody
  • Pain in the lower back or on the side of the body

Yes. Call your doctor or nurse right away if you have any of the symptoms listed above, especially if you know that you have high blood pressure.

Yes. Your doctor or nurse will ask about your symptoms, do an exam, and check your blood pressure. They might use a special light to look in the back of your eyes.

Your doctor will also do tests to check how serious your condition is. Tests can include:

  • Blood tests
  • Urine tests
  • A chest X-ray
  • A CT scan or other imaging test of your brain – Imaging tests create pictures of the inside of the body.
  • A CT scan or other imaging test of your chest
  • An ECG (also called an “electrocardiogram”) – This test measures the electrical activity in your heart.

A high blood pressure emergency is treated in the hospital. Your doctor will give you medicines to lower your blood pressure quickly. These medicines are usually given through a thin tube that goes into your vein, called an “IV.”

Your doctor will also treat any problems caused by your very high blood pressure, if they can be treated.

People who have a high blood pressure emergency usually need long-term treatment to keep their blood pressure under control. This usually includes:

  • Taking medicines
  • Following a low-salt diet that includes a lot of fruits and vegetables
  • Losing weight (if you are overweight)
  • Getting regular exercise