All You Need to Know About Blood Pressure Medications

Nearly half of adults in the United States have high blood pressure or hypertension. When it’s not controlled, this condition can increase the risk of heart disease, stroke, kidney failure, vision loss, memory problems, and premature death. 

To help combat hypertension, your doctor may prescribe healthy lifestyle changes, including diet and exercise recommendations.They also may prescribe one of the different medications that can help control blood pressure.

In this article, I’ll talk about what your blood pressure is and why it can become elevated. I’ll then describe some common types of blood pressure medications, including their differences and potential side effects. 

What is Blood Pressure?

Blood pressure is the force of blood pushing against artery walls as it flows. This pressure is determined by the amount of blood being pumped by your heart, how hard it’s being pumped, and the amount of resistance to the blood flow.

The resistance can be changed by the narrowing or widening of your arteries. Blood pressure is measured using two numbers: systolic pressure and diastolic pressure.

Blood pressure readings are reported with the systolic number first and the diastolic number second, such as 120 “over” 80, or 120/80 millimeters of mercury, or mm Hg. Normal blood pressure for adults is a systolic blood pressure that is lower than 120, and a diastolic blood pressure that is lower than 80.

The first (or “top”) number in a blood pressure reading (the systolic blood pressure) is the pressure when the heart contracts and sends blood outward to the body, away from the heart.

The second (or “bottom”) number (the diastolic blood pressure) is the pressure when the heart is relaxed and collects returned blood from the veins.

Low Blood Pressure

If your blood pressure falls below 90/60, it is considered significantly low blood pressure, also called hypotension. Some people have lower blood pressure all the time without symptoms. This is not considered a problem if they otherwise feel well, and if this is chronic for them. However, some symptoms can occur with low blood pressure.

These include:

• Lightheadedness
• Weakness
• Dizziness
• Feelings of faintness

Low blood pressure can be caused by dehydration, loss of blood, aging, pregnancy, diabetes, medication or non-prescription side effects, or too much blood pressure medication.

High Blood Pressure

When your blood pressure is too high, it’s called hypertension, or simply high blood pressure. High blood pressure can sometimes occur in an acute or sudden way—your blood pressure changes during the day based on what you are doing and can go up in response to stress, fear, fatigue, or pain. 

However, if your blood pressure is chronically high, meaning that it reads above normal on several different days and times, you may be diagnosed with high blood pressure.

If it is not treated, it can lead to serious health problems such as kidney disease, common artery disease, or some other cardiovascular event.

Hypertension falls into different categories depending on the readings:

• Elevated blood pressure: Higher than 120/80 and up to 130/80
• Stage 1 hypertension: 130/80 but lower than 140/90
• Stage 2 hypertension: 140/90 or higher
• Hypertensive emergency: Go to the ER immediately or call 9-1-1 if systolic pressure is 180 or higher and/or diastolic pressure is 120 or higher.

Both Stage 1 and Stage 2 hypertension can be treated effectively with blood pressure medications, diet, and lifestyle changes. Your health care provider will likely recommend a combined approach to help address your high blood pressure.

A hypertensive crisis occurs when either the systolic number stays higher than 180 or when the diastolic number is higher than 100, and you are having symptoms like headache, vision changes, chest pain, nausea, or shortness of breath.

Elevated blood pressure without any symptoms is not necessarily considered an emergency, but persistently high readings should be discussed with your primary care provider as soon as possible. 

When your blood pressure is elevated over time, even mildly, it can increase your risk for other health issues. These can include cardiovascular disease, heart attack, or stroke.

In fact, recent studies show the risk of death from heart disease and stroke doubles with every 20 mm Hg systolic or 10 mm Hg diastolic increase among people from age 40 to 89.

Your medical provider will work with you to create a treatment plan that keeps your blood pressure levels in a safe range. This often includes a combination of dietary and lifestyle adjustments along with blood pressure medication.

Common Blood Pressure Medications

There are different ways to lower blood pressure, and one of the most effective is the use of medications. There are many different FDA-approved medications to treat high blood pressure.

Most blood pressure medications work in one of the following ways:

• Removing excess water from the body, which balances fluids and salt. This helps your kidneys regulate the amount of blood in your blood vessels.
• Reducing tension within blood vessel walls
• Decreasing the force with which the heartbeats
• Interrupting nerve activity that can lead to blood vessel constriction

Your doctor or provider will help to determine which blood pressure medicines work best for you or other medical conditions you may have. Most of the time, one type of drug is used, but in some cases or more advanced stages of hypertension, a combination of medications may be used for patients.

Medications designed to lower blood pressure are divided into different categories based on how they work. Within those categories, there are different types of brand names and generic drugs. Your doctor will recommend the best treatment options.

Beta blockers

Beta blockers act to reduce both the heart rate and blood pressure. 

Common beta-blockers include:

• Acebutolol (Sectral)
• Atenolol (Tenormin, Senormin)
• Betaxolol (Kerlone, Betoptic)
• Bisoprolol (Zebeta)
• Bisoprolol-hydrochlorothiazide (Ziac)
• Metoprolol tartrate (Lopressor)
• Metoprolol succinate (Toprol-XL)
• Nadolol (Corgard)
• Pindolol (Visken)
• Propranolol (Inderal, InnoPran XL, Hemangeol)
• Sotalol (Betapace, Sorine, Sotalol AF)
• Timolol (Timoptic, Betimol)

Alpha blockers

While they are not used as commonly, alpha blockers work by blocking a hormone called norepinephrine from tightening the walls of your blood vessels. Like beta blockers, they also reduce blood pressure.

Types of alpha blockers include:

• Alfuzosin (Uroxatral)
• Doxazosin (Cardura, Cardura XL)
• Prazosin (Minipress)
• Silodosin (Rapaflo)
• Tamsulosin (Flomax)
• Terazosin (Hytrin) 

Combined alpha and beta blockers

Combined alpha and beta blockers may be prescribed for patients who have an increased risk of developing heart conditions like heart failure. They work together to prevent the binding of certain hormones known as catecholamines at both alpha and beta receptor sites.

By doing this, they can both slow how blood vessels constrict and how quickly and forcefully the heartbeats. These drugs are sometimes called “Beta blocker, with alpha activity.” 

Typical combination alpha-beta blockers include:

• Carvedilol (Coreg)
• Labetalol (Trandate, Normodyne)

Blood vessel dilators

Also known as vasodilators, these drugs relax the muscles that control blood vessel walls. They work to dilate or widen the blood vessel walls. When the blood vessels are wider, the pressure of the fluid flowing through them is lower.

These medications are especially effective for arterioles and small arteries that can more easily become blocked. 

Common blood vessel dilator drugs include:

• Hydralazine (Apresoline, Adrolazine, Apresrex)
• Nitroglycerin

Calcium channel blockers

Calcium is an important mineral, not just for bone health but also for blood pressure. To properly contract, muscles need calcium both in and out of the muscle cells.

Calcium channel blockers prevent some calcium from being taken into the muscle cells of the heart and blood vessels. When there is more calcium in these cells, your heart pumps harder. By blocking some calcium, the heart doesn’t pump as forcefully—lowering your blood pressure. 

Types of calcium channel blockers include:

• Amlodipine (Norvasc, Katerzia)
• Diltiazem (Cardizem, Tiazac, Cartia XT)
• Felodipine (Plendil)
• Isradipine (DynaCirc)
• Nicardipine (Cardene)
• Nifedipine (Procardia, Adalat CC, Nifediac CC)
• Nisoldipine (Sular)
• Verapamil (Calan, Isoptin, Verelan)

Diuretics

Diuretics, also called “water pills”, help the kidneys to remove excess salt and fluids from the body. With less retained fluid, blood pressure can decrease.

When prescribed for high blood pressure, diuretics are often used in conjunction with other medications. There are three kinds of diuretics. Thiazide diuretics are the most commonly prescribed diuretics for blood pressure problems.

Loop diuretics are most commonly used for heart failure. Potassium-sparing diuretics are used if too much potassium is being lost, which is a potential side effect of thiazide diuretics.

Commonly used thiazide diuretics include:

• Chlorothiazide (Diuril, Chlorulan, Dithirex, others)
• Hydrochlorothiazide (Microzide, Esidrix, Aqua-Cen)
• Indapamide (Lozol)
• Metolazone (Zaroxolyn)

Examples of loop diuretics include:

• Bumetanide (Bumex)
• Furosemide (Lasix, Diaqua-2, Delone)
• Torsemide (Demadex)

Examples of potassium-sparing diuretics are:

• Amiloride (Midamor)
• Spironolactone (Aldactone, CaroSpir, Spirazone)
• Triamterene (Dyrenium)

Central agonists and Alpha-2 receptor agonists

Central agonists and alpha-2 adrenergic receptor agonists are drugs that act on the central nervous system to relax blood vessels.

They prevent catecholamines from being released, which can increase the rate and pressure with which the heart pumps.

Examples of these agonist drugs include:

• Methyldopa (Aldomet, L-Dopres)
• Clonidine (Catapres)
• Guanfacine (Tenex, Intuniv ER)

Angiotensin II receptor blockers

Angiotensin II receptor blockers, sometimes shortened to ARBs, work similarly to other classes of blood pressure drugs. They intercept the activity of angiotensin II, which binds with blood vessels to tighten them.

When your body produces angiotensin, it needs to react with a “receptor”—kind of like the lock a key would go into.

ARBs act to lower blood pressure by blocking these receptors, so that even though your body produces angiotensin, it doesn’t take effect.

Examples of angiotensin receptor blockers include:

• Candesartan (Atacand)
• Eprosartan (Teveten)
• Irbesartan (Avapro)
• Losartan (Cozaar)
• Telmisartan (Micardis)
• Valsartan (Diovan)

ACE inhibitors

Angiotensin-converting enzyme inhibitors, also known as ACE inhibitors, work on the same chemical as ARBs. But unlike ARBs, which block the receptor of angiotensin, ACEs help the body produce less angiotensin. This lowers blood pressure because the blood vessels don’t narrow in response to it.

Examples of ACE inhibitor drugs include:

• Benazepril (Lotensin)
• Captopril (Capoten)
• Enalapril (Vasotec, Epaned)
• Fosinopril (Monopril)
• Lisinopril (Prinivil, Qbrelis, Zestril)
• Moexipril (Univasc)
• Perindopril (Aceon)
• Quinapril (Accupril tablets)
• Ramipril (Altace)
• Trandolapril (Mavik)

According to the American Heart Association, ACE inhibitors may cause impaired kidney function in rare cases. 

In March 2022, Pfizer did a press release announcing the voluntary recall of five lots of the drug Accupril also known as quinapril HCL distributed by the company because of a high presence of nitrosamine. According to the release, the nitrosamine, N-nitroso-quinapril is a known carcinogen and is present in a high dose (above the Acceptable Daily Intake level). 

Even though the drugs went through robust clinical trials by an efficient research team and have been marketed for use for over 20 years, Pfizer advises that patients currently taking the medication consult with their healthcare providers about alternative treatment options.

Renin-inhibitors

Direct renin inhibitors are a newer class of drugs for hypertension. When your blood pressure drops or the volume of blood in your blood vessels is low, your kidney releases a chemical called renin.

This chemical reacts with another chemical, angiotensinogen. This process ultimately leads to the production of angiotensin II—the same chemical that’s blocked by ACE inhibitors.

By blocking renin, direct renin inhibitors block angiotensin from being created—and thus, lower blood pressure.

An example of renin inhibitors includes:

• Aliskiren (Tekturna)

Aldosterone receptor antagonists

Aldosterone receptor antagonists have a similar mechanism of action to diuretics. They block aldosterone, a chemical that influences the kidneys and colon in how they release sodium into the bloodstream. By blocking aldosterone, blood pressure can be decreased.

Examples of aldosterone receptor antagonists include:

• Eplerenone (Inspra)

Typically, your doctor or healthcare provider will prescribe you high blood pressure medication when indicated, along with a healthy diet and lifestyle changes.

Keep your provider informed of all supplements, exercise, and other lifestyle habits and changes. Increasing or decreasing these could change your medication requirements or drug dosage needs.

As with any medication, it’s important to follow prescription instructions and keep your provider updated on how you’re feeling. Sometimes medications may need to be changed or adjusted based on how you respond.

Possible Side Effects of Blood Pressure Medication

Many of the more common side effects of blood pressure medications decrease with time as your body adjusts to them.

Always ask your prescriber about possible side effects and let them know if there are changes to how you are feeling. They may have to prescribe a different medicine for you if you are experiencing some side effects.

Dizziness

Because medications for high blood pressure work to decrease it, you may feel dizzy or lightheaded as you get used to the change. For many, this side effect is temporary.

Constipation

Diuretics can have a side effect of constipation. Reduced fluids in the body can lower blood pressure, but this reduction can also make bowel movements harder to pass.

Drinking enough fluids and eating more fiber as part of a healthy diet can help address this. Over-the-counter stool softeners can also help.

Headache

Because the brain is highly sensitive to even small changes in the pressure in veins and arteries, changes can result in headaches.

If your headaches get worse or do not improve over time, speak with your provider about it. Staying hydrated is also important since dehydration can trigger headaches unrelated to blood pressure medication.

Since some blood pressure medications remove extra fluids, you may become dehydrated if you’re not consuming enough fluids.

Depression

Some types of blood pressure medications, like beta-blockers, can cross the blood-brain barrier. This may result in mood changes or, in rare cases, depression.

Not all of them carry this risk, and some research even finds that the association is weak or nonexistent. If you notice mood changes or severe side effects, such as depression, after starting blood pressure medication, speak with your provider. They may have to prescribe another medication for best results.

Don’t suddenly discontinue medication for hypertension; this can suddenly impact your blood pressure levels.

Other possible side effects

Some other common side effects or related health problems of hypertension medications include:

• Erectile dysfunction
• Fatigue or lack of energy
• Nausea and vomiting
• Skin rashes
• Kidney problems
• Change in weight without trying

When to See a Doctor or Healthcare Professional

You should consult with a doctor or primary care provider if you experience symptoms of high blood pressure.

These can include headaches, shortness of breath, nosebleeds, or feelings of pulse or pressure in your head or elsewhere in your body. If you have a family history of high blood pressure, you may be more likely to have it, too.

If you have more than one abnormal or high blood pressure reading over a week or two, it’s a good idea to speak with a medical professional.

In addition to prescribing high blood pressure medicines, your doctor may suggest other blood pressure  control methods, such as physical activity, having a quality sleep at night, and eating healthy food such as the DASH diet and low-fat diets. You may also have to watch the type of drinks you take.

The Centers for Disease Control and Prevention (CDC) advises that in order to help keep blood pressure within the healthy range, people should limit alcohol consumption. 

How K Health Can Help

If you have concerns about your blood pressure or know that you need medication, it can feel challenging to maintain frequent check-ins with your primary care physician.

K Health offers affordable and convenient access to highly qualified doctors to treat and manage high blood pressure, as long as you are not having a hypertensive crisis.

You can meet with your K Health doctor from the comfort of your own home via the K Health app, all while knowing that you’re getting individualized and expert care.

If you are experiencing headaches, chest pain, vision changes, or dizziness along with high blood pressure, go to the emergency room or call 9-1-1.