Angiotensin II Receptor Blockers (ARBs)

Description

This group of medicines is known as Angiotensin II Receptor Blockers, or ARBs. ARBs are used in the treatment of high blood pressure (hypertension). These agents work by blocking the actions of angiotensin II (a substance produced by the body to constrict blood vessels and raise blood pressure). Blocking the action of angiotensin II lowers blood pressure. These agents may also be used for other conditions as determined by your doctor.

Before Using This Medicine

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For the ARBs, the following should be considered:

Allergies -- Tell your doctor if you have ever had any unusual or allergic reaction to the alpha-blocker medicine prescribed. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy -- Before taking any of these medicines, make sure your doctor knows if you are pregnant or if you may become pregnant. Most drugs in this class are contraindicated during pregnancy, especially in the second and third trimesters

Breast-feeding -- Candesartan, eprosartan, and telmisartan have been shown to enter breast milk, use caution. It is not known whether losartan, irbesartan, olmesartan, and valsartan passes into breast milk; use is contraindicated/not recommended.

Older adults -- Some side effects are more likely to occur in the elderly, who are usually more sensitive to the effects of alpha-blockers.

Other medicines -- Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking or receiving an ARB, it is especially important that your health care professional know if you are taking any of the following:

• Lithium
• NSAIDs
• Potassium-sparing diuretics (amiloride, spirinolactone, potassium, triamterene)
• Potassium supplements
• High dose trimethoprim

Other medical problems -- The presence of other medical problems may affect the use of the ARBs. Make sure you tell your doctor if you have any other medical problems, especially:

• Kidney disease
• Liver disease
• Significant aortic/mitral stenosis
• Volume depletion (correct before initiating ARB therapy)

Proper Use of This Medicine

To help you remember to take your medicine, try to get into the habit of taking it at the same time each day.

For patients taking this medicine for high blood pressure :

• In addition to the use of the medicine your doctor has prescribed, treatment for your high blood pressure may include weight control and care in the types of foods you eat, especially foods high in sodium. Your doctor will tell you which of these are most important for you. You should check with your doctor before changing your diet.
• Many patients who have high blood pressure will not notice any signs of the problem. In fact, many may feel normal. However, if high blood pressure is not treated, it can cause serious problems such as heart failure, blood vessel disease, stroke, or kidney disease.
• Remember that this medicine will not cure your high blood pressure but it does help control it. It is very important that you take your medicine exactly as directed, even if you feel well. You must continue to take it as directed if you expect to lower your blood pressure and keep it down. You may have to take high blood pressure medicine for the rest of your life. Also, it is very important to keep your appointments with your doctor, even if you feel well.

Storage --

To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

Precautions While Using This Medicine

It is important that your doctor check your progress at regular visits. This is to make sure the medicine is working for you and to allow the dosage to be changed if needed.

Do not stop taking this medicine without first checking with your doctor. Your doctor may want you to reduce gradually the amount you are taking before stopping completely. Some conditions may become worse when the medicine is stopped suddenly, and the danger of heart attack is increased in some patients.

Make sure that you have enough medicine on hand to last through weekends, holidays, or vacations. You may want to carry an extra written prescription in your billfold or purse in case of an emergency. You can then have it filled if you run out of medicine while you are away from home.

Your doctor may want you to carry medical identification stating that you are taking this medicine.

Before having any kind of surgery (including dental surgery) or emergency treatment, tell the medical doctor or dentist in charge that you are taking this medicine.

This medicine may cause some people to become dizzy, drowsy, or lightheaded. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy or are not alert. If the problem continues or gets worse, check with your doctor.

Before you have any medical tests, tell the doctor in charge that you are taking this medicine. The results of some tests may be affected by this medicine.

For patients taking this medicine for high blood pressure :

• Do not take other medicines unless they have been discussed with your doctor. This especially includes over-the-counter (nonprescription) medicines for appetite control, asthma, colds, cough, hay fever, or sinus problems since they may tend to increase your blood pressure.

Side Effects of This Medicine

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• Chest pain or palpitations
• Unrelenting headache
• Swelling of extremities, face, or tongue
• Muscle weakness or pain
• Respiratory difficulty or unusual cough
• Flu-like symptoms
• Persistent adverse reactions
• Signs and symptoms of overdose (in the order in which they may occur)
• Hypotension, drowsiness, and shock

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:

• Dizziness, fainting, or lightheadedness
• Postural hypotension
• Diarrhea
• Decreased libido (will resolve)

Although not all of the side effects listed above have been reported for all of these medicines, they have been reported for at least one of them. Since all of the ARBs are very similar, any of the above side effects may occur with any of these medicines. However, they may be more or less common with some agents than with others.

• After you have been taking an ARB for a while, it may cause unpleasant or even harmful effects if you stop taking it too suddenly.

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.