Side Effects of High Blood Pressure Medications

Medically Reviewed by Jabeen Begum, MD on May 29, 2024
10 min read

Any medication can cause side effects, and medications for high blood pressure (hypertension) are no exception. While many people taking high blood pressure medication have only mild or no side effects, it's important to work closely with your doctor to manage any side effects you may have. There are lots of ways to manage these issues.

This article lists the side effects that may be caused by each type of high blood pressure drug. First, here are four general warnings.

Never stop taking medication without first talking to your doctor. In some cases, this can be very dangerous, causing a big spike in blood pressure.

If you are pregnant or planning to get pregnant, talk to your doctor about the safest medication to use. Angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs) can cause harmful side effects for pregnant people and their developing babies.

If you take insulin for diabetes, talk to your doctor. Changes in blood sugar can occur in people with diabetes taking diuretics or beta-blockers for high blood pressure.

If you have problems with erections during sex, talk with your doctor. Some high blood pressure medications can cause this problem. Reducing the dose or changing to another type of medication may help. But high blood pressure itself can also cause erectile dysfunction.

Today, there are more medication options than ever for managing high blood pressure (hypertension). While some side effects -- such as dizziness when you stand up -- can happen with any drug that lowers your blood pressure, each drug comes with its own potential side effects. So, anytime you get a new prescription for your high blood pressure, be sure to read about it and its possible side effects. You can find a full list on your medication insert.

Here's what you need to know about each major type.

Diuretics (water pills)

These high blood pressure medications flush extra water and sodium (salt) from your body. Diuretics may cause these side effects:

  • Extra urination. Extra water out means more time in the bathroom. Take these medications earlier in the day and when you're not far away from a bathroom.
  • Erection problems in some men
  • Weakness, leg cramps, or fatigue. Diuretics may decrease the body's potassium levels, which can lead to these side effects. Certain potassium-sparing diuretics do not have this effect, however.
  • Intense and sudden foot pain, which is a symptom of gout — a rare side effect


Beta-blockers make your heart beat less forcefully and more slowly. These medications may cause side effects such as:

Angiotensin-converting enzyme (ACE) inhibitors

These high blood pressure medications block the formation of a hormone that causes blood vessels to narrow, so vessels relax. ACE inhibitors may cause these side effects:

  • A dry, hacking cough that doesn't go away.
  • Skin rash and a loss of taste.

Angiotensin II receptor blockers (ARBs)

These high blood pressure medications shield blood vessels from a hormone that causes blood vessels to narrow. This allows blood vessels to stay open. One of the more common side effects of ARBs is dizziness.

Calcium channel blockers (CCBs)

These high blood pressure medications keep calcium from entering heart muscle and blood vessel cells. Blood vessels can then relax. CCBs may cause these side effects:


These reduce nerve impulses to blood vessels, allowing blood to flow more easily. These medications may cause:

  • Dizziness, lightheadedness, or weakness when standing up suddenly or getting up in the morning (from reduced blood pressure)
  • Fast heart rate

Alpha-2 receptor agonists

These medications decrease activity in the adrenaline-producing part of the nervous system. They may cause:

  • Drowsiness
  • Dizziness


These high blood pressure medications reduce nerve impulses and also slow the heartbeat. Patients with severe high blood pressure often receive them by intravenous (IV) injection. But doctors may also prescribe them for people who have congestive heart failure. Alpha-beta-blockers may cause a drop in blood pressure when you stand up suddenly or get up in the morning. This can cause dizziness, lightheadedness, or weakness.

Central alpha-adrenoceptor agonists

These high blood pressure medications control nerve impulses, relaxing blood vessels.

Central agonists may cause:

  • Anemia
  • Constipation
  • Dizziness, lightheadedness, or weakness when standing up suddenly or getting up in the morning (from a drop in blood pressure)
  • Drowsiness
  • Dry mouth
  • Erection problems
  • Fever

Peripheral adrenergic inhibitors

This type of medication blocks neurotransmitters in the brain, so the message to constrict doesn't reach smooth muscles. Used less often than other high blood pressure medications, these drugs can cause:

  • Diarrhea
  • Dizziness, lightheadedness, or weakness when standing up suddenly or getting up in the morning (from reduced blood pressure)
  • Erection problems
  • Heartburn
  • Stuffy nose

If nightmares or insomnia persist, talk with your doctor about another medication for high blood pressure.


Vasodilators relax muscles in vessel walls, opening blood vessels and allowing blood to flow better. These medications may cause:

  • Excessive hair growth
  • Fluid retention
  • Headaches
  • Irregular or very rapid heartbeat (palpitations)
  • Joint aches and pains
  • Swelling around the eyes

Renin inhibitors

This newer class of high blood pressure medication works by decreasing chemicals that tighten blood vessels. This medication may be used alone or in combination with another medication. Side effects may include:

Combination medicines

You might start high blood pressure treatment with just one drug, or your doctor may prescribe two. If the first drug or combination doesn't get your blood pressure down enough, even with dosage increases, another medication may be added. The choice of drugs can vary, depending on factors such as whether you have diabetes, heart failure, or chronic kidney disease. In some cases, medications will be combined into single pills.

Sometimes, using two or three drugs will give you fewer side effects than continuing to raise the dose of a single drug. For example, you might be less likely to get swollen ankles from a calcium channel blocker if you take it in a low dose along with an ACE inhibitor, rather than in a high dose by itself.

Other times, a combination will raise your risks of side effects. For example, if you take diuretics and beta-blockers together, you may get better blood pressure control but have a higher risk of blood sugar problems, fatigue, and sexual dysfunction.

It's rare to get severe side effects from your high blood pressure medications. But they can happen. They vary depending on the medicines you take and the doses. Read the insert that comes with your medicine for warnings and advice about when to call your doctor.

Here are some possible side effects of common blood pressure drugs that you should report to your doctor immediately.

ACE inhibitors: Abdominal pain, chest pain, fast heartbeat, yellowed skin, problems breathing or swallowing, signs of infection, or swelling in your lips, tongue, or throat. Sudden swelling could be a sign of a condition called angioedema, which is a medical emergency

Beta-blockers: Chest pain, problems breathing, slow or irregular heartbeat, or swelling in your hands, feet, ankles, or legs.

Calcium channel blockers: Chest pain, serious rashes, fainting, irregular heartbeat, or swelling of the face, eyes, lips, tongue, arms, or legs. 

Diuretics (water pills): Sudden vision changes or eye pain, severe rash, problems breathing, irregular heartbeat, unusual thirst, muscle cramps or weakness, or tingling or numbness in the arms, legs, or feet.

Any new medication can cause a rare allergic reaction. Call 911 right away if you develop hives, wheezing, vomiting, light-headedness, or swelling in your throat or face.

Is it dangerous to take a double dose of blood pressure medication?

If you take a double dose by accident, you could get some extra side effects. One risk is a sudden drop in blood pressure, which could make you feel lightheaded, dizzy, and nauseated. 

Different blood pressure medications come with different potential effects if you take a double dose. For example, if you take an extra water pill (diuretic), you probably won't have any serious problems, but will want to drink plenty of fluids to prevent dehydration. If you take an extra dose of a beta-blocker, it could be a more serious situation because it can slow down your heart and make it hard to breathe. The amount needed to cause an overdose varies from person to person, so call your doctor right away if you take too much.

For information about what to do if you take an extra dose of your specific blood pressure drugs, you can call your pharmacist or a poison control center.

Many common side effects of blood pressure drugs tend to decrease over time as your body gets used to lower blood pressure levels. These include symptoms such as dizziness, drowsiness, and lightheadedness.

But some side effects can continue or develop after you've taken the drug for a while. For example, taking diuretics might lead to low levels of potassium in your body, which could cause muscle weakness and heart problems if you don't address the problem. Diuretics can also worsen gout. And alpha-blockers may increase the risk of heart failure.

Early research has suggested a link between taking ACE inhibitors and an increased risk of kidney damage. But researchers say more study is needed to confirm the link and that patients shouldn't stop taking those medicines.

One large study suggested that thiazide water pills (diuretics) have fewer side effects and work better on average than other drugs commonly prescribed as first treatments for high blood pressure.

But that doesn't mean they are the best choice for everyone. For example, if you have kidney disease or heart failure, doctors usually advise starting with other kinds of drugs. It's important to work with your doctor to find the safest and most effective drug or combination for you.

If you're bothered by high blood pressure medication side effects, it's important to work with your doctor. You should never stop a blood pressure medicine or change the dose without medical advice.

Some strategies you might try, with your doctor's guidance, include:

  • Giving your medicine more time, as some initial side effects may go away
  • Keeping a side effect journal so you see how, when, and how often they happen
  • Getting up slowly from sitting or lying down, to minimize dizziness and the risk of falling
  • Keeping track of your potassium levels if you're taking a diuretic and then following your doctor's advice about how to manage your levels
  • Keeping close tabs on your blood pressure at home, so you can report low readings (linked with side effects such as dizziness and fatigue) or high readings (suggesting your medicine isn't working)
  • Making lifestyle changes, such as reducing salt in your diet and increasing physical activity, to help your medicines work better and reduce the need for higher doses or added medicines

If side effects are still an issue, ask your doctor if you can:

  • Change your prescribed dose of medicine
  • Change the time of day you take the medicine -- which might help with issues such as nighttime peeing or daytime drowsiness
  • Switch to a different drug
  • Try a new combination of drugs - which may allow you to use lower doses with fewer side effects

Contact your doctor if:

  • Your blood pressure readings are too high or too low
  • You have new potential side effects
  • You start taking any supplements or medications they don't know about since these can interact with your blood pressure drugs
  • You have a new medical condition they don't know about

If you have severe symptoms, such as sudden swelling in your face, breathing problems, or fainting, get emergency medical care.


Blood pressure drugs can have a wide range of side effects. Some go away after you take the medicine for a while, but if you're bothered by persistent side effects, it's important to talk to your doctors about solutions. You should never reduce your dose or stop taking a blood pressure drug without medical advice.

What are the symptoms if your blood pressure medication is too strong?

If your medicine makes your blood pressure too low or lowers it too quickly, you could have symptoms such as dizziness, fainting, nausea, and tiredness. That's one reason doses are usually increased gradually. But feeling some of these symptoms when you first start your medication doesn't always mean it's too strong. You may just need time to get used to it.

Do blood pressure medicines do more harm than good?

No, not usually. The long-term health threats associated with uncontrolled high blood pressure, such as strokes and heart attacks, are often far more dangerous than any side effects associated with blood pressure drugs. The benefits of drug treatment are greatest for people who are at the highest risk for strokes, heart attacks, and other cardiovascular problems because of their high blood pressure, other health problems, age, and other factors. If you have mild hypertension, your doctor may recommend trying lifestyle changes, such as exercising more and eating less salt, so that you can avoid medication side effects.