Healthy Heart

What Are Antihypertensive Drugs?

What Are Antihypertensive Drugs?


Medications that help treat hypertension are called antihypertensive drugs, which are divided into different categories. These medications work differently with different side effects. Because there are many antihypertensive drugs available, finding the best medication and treatment plan for you may take some time. Your healthcare provider can help you with a specific treatment plan to effectively control your blood pressure. 

Hypertension or high blood pressure is when your blood pressure becomes abnormally and consistently high. It happens when blood forces and pushes against blood vessel walls. Although you may not feel any symptoms of hypertension, an undiagnosed and untreated high blood pressure can cause damage and serious health problems, such as stroke, heart disease, and kidney disease. For this reason, early detection and treatment of high blood pressure are very important to help prevent these conditions.


Diuretics also called water pills, are medications that help treat hypertension and other conditions. These medications work by helping the kidneys expel excess water and salt from the body. They lower your blood pressure by reducing the volume of blood that passes through your blood vessels. Diuretics are also one of the most commonly used medications for the treatment of high blood pressure.

There are three different types of diuretic drugs, which enable the body to get rid of more fluids as urine. They are:

  • Loop Diuretics: This type of diuretic drug causes the kidneys to expel more urine, lowering blood pressure and the amount of water in the body. They are usually prescribed for the treatment of heart failure. Some examples of loop diuretics are furosemide (Lasix), torsemide (Demadex), ethacrynic acid (Edecrin), and bumetanide (Bumex).
  • Thiazide Diuretics: These medications help reduce the amount of water and salt in your body. They also help lower blood pressure by dilating blood vessels. Thiazide diuretics are usually given as the first medication for the treatment of hypertension. They also have fewer side effects than other types of diuretics when they are taken in low doses. Examples of thiazide diuretics are methyclothiazide (Aquatensen), hydroflumethiazide (Diucardin), chlorthalidone (Hygroton), indapamide (Lozol), hydrochlorothiazide (Hydrodiuril, Microzide), chlorothiazide (Diuril), and metolazone (Zaroxolyn).
  • Potassium-Sparing Diuretics: Unlike other types of diuretics that can reduce potassium levels in the body, potassium-sparing diuretics help reduce fluid in the body without losing potassium. Having low levels of potassium can lead to abnormal health conditions, such as arrhythmia. These medications are usually prescribed along with another type of diuretic because they do not effectively lower blood pressure levels like thiazide diuretics do. Examples of this type of diuretic are spironolactone (Aldactone), triamterene (Dyrenium), and amiloride (Midamor). 

Beta Blockers

Beta-blockers are drugs that help reduce high blood pressure. They work by blocking the effects of epinephrine on the heart. They are also called as beta-adrenergic blocking agents, which help improve the flow of blood by opening up the blood vessels.

When beta blockers are taken, the heart beats slowly and with less force. They help reduce blood pressure because they enable the heart to pump less volume of blood through the blood vessels with every beat. They are also prescribed for the prevention of future heart attacks in people who previously had a heart attack.

The most commonly prescribed beta blockers are:

Angiotensin-Converting Enzyme (ACE) Inhibitors

ACE inhibitors are medications that help reduce blood pressure by allowing the blood vessels to expand and letting more blood through. They work by reducing the body’s production of the hormone called angiotensin II, which causes narrowing of the blood vessels.

Some examples of ACE inhibitors are:

Angiotensin II Receptor Blockers (ARBs)

ARBs and ACE inhibitors have similar effects but with different mechanisms. ARBs are medications that block the effects of the chemical called angiotensin II. These medications reduce high blood pressure levels by dilating blood vessels and allowing the blood to easily flow. Doctors often prescribe ARBs to people who are unable to take ACE inhibitors.

Commonly prescribed ARBs include:

Alpha-1 Blockers

Catecholamines are hormones released by the body in response to emotional or physical stress. Norepinephrine and epinephrine are catecholamines that can constrict blood vessels and cause your heart to beat faster with more force. These effects tend to increase blood pressure levels when catecholamines bind to a receptor called alpha-1 receptor.

Alpha-1 blockers work by binding with alpha-1 receptors and block the attachment of catecholamines to the receptors. These medications help lower blood pressure levels by preventing the narrowing of blood vessels.

Alpha-1 blockers include:

Combined Alpha and Beta Blockers

Combined alpha and beta blockers are usually administered to patients as an IV drip, especially during a hypertensive crisis. These medications may also be prescribed for outpatients who are at risk for heart failure.

They work by decreasing blood vessel constriction like alpha-1 blockers, and slow the heart rate like beta-blockers. The most common alpha-beta-blockers are labetalol hydrochloride (Normodyne) and carvedilol (Coreg). 

Calcium Channel Blockers

The in and out movement of calcium in the muscle cells is necessary for the muscles to contract. These medications can help lower blood pressure by limiting calcium from entering the heart’s smooth muscle cells and blood vessels, slowing the heart rate and allowing less force in every heartbeat.

Some examples of calcium channel blockers are:


Vasodilators are medications that help reduce high blood pressure by relaxing the blood vessels and increasing blood and oxygen supply to the heart. These medications are often prescribed to help relieve angina or chest pain. Examples of vasodilators are hydralazine (Apresoline) and minoxidil (Loniten). 

What are the side effects of antihypertensive drugs?

Any type of medication has side effects, including antihypertensive drugs. However, most side effects of antihypertensive drugs are usually mild and tend to go away over time. The side effects of high blood pressure medications may include any of the following:

Inform your doctor if you experience any of these side effects and if they are causing discomfort or problems. Your healthcare provider may change your medication or adjust the dose of your medication to help reduce the side effects.