Atenolol is used alone or together with other medicines (such as hydrochlorothiazide) to treat high blood pressure (hypertension). High blood pressure adds to the workload of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys, resulting in a stroke, heart failure, or kidney failure. High blood pressure may also increase the risk of heart attacks. These problems may be less likely to occur if blood pressure is controlled .

Atenolol is also used to help prevent chest pain and to decrease the severity of heart attacks .

This medicine is a beta-blocker. It works by affecting the response to nerve impulses in certain parts of the body, like the heart. As a result, the heart beats slower and decreases the blood pressure. When the blood pressure is lowered, the amount of blood and oxygen is increased to the heart .

This medicine is available only with your doctor's prescription .

In addition to the use of this medicine, treatment for your high blood pressure may include weight control and changes 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. It is very important that you take your medicine exactly as directed and that you keep your appointments with your doctor even if you feel well .

Remember that this medicine will not cure your high blood pressure, but it does help control it. 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. If high blood pressure is not treated, it can cause serious problems such as heart failure, blood vessel disease, stroke, or kidney disease .

Do not interrupt or stop taking this medicine without first checking with your doctor. Your doctor may want you to gradually reduce the amount you are taking before stopping it completely. Some conditions may become worse when the medicine is stopped suddenly, which can be dangerous .

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 immediately if any of the following side effects occur:

More common

Blurred vision

cold hands or feet

confusion

difficult or labored breathing

dizziness, faintness, or lightheadedness when getting up from a lying or sitting position suddenly

shortness of breath

sweating

tightness in chest

unusual tiredness or weakness

wheezing

Less common

Anxiety

chest pain or discomfort

chills

cold sweats

cough

dizziness or lightheadedness

fainting

fast heartbeat

leg pain

noisy breathing

slow or irregular heartbeat

sudden shortness of breath or troubled breathing

Rare

Bloody urine

decreased frequency or amount of urine

increased blood pressure

increased thirst

loss of appetite

lower back or side pain

nausea

swelling of face, fingers, or lower legs

vomiting

weight gain

Incidence not determined

Black, tarry stools

bleeding gums

blood in urine or stools

blurred or loss of vision

bone or joint pain

disturbed color perception

double vision

feeling that others are watching you or controlling your behavior

feeling that others can hear your thoughts

feeling, seeing, or hearing things that are not there

fever

halos around lights

night blindness

overbright appearance of lights

paleness or cold feeling in fingertips and toes

pinpoint red or purple spots on skin

severe mood or mental changes

skin irritation or rash, including rash that looks like psoriasis

skin rash, hives, or itching

sore throat

swollen or painful glands

tingling or pain in fingers or toes when exposed to cold

tunnel vision

unusual behavior

unusual bleeding or bruising

Get emergency help immediately if any of the following symptoms of overdose occur:

Symptoms of overdose

Anxiety

coma

cool, pale skin

depression

dilated neck veins

extreme fatigue

headache

increased hunger

irregular breathing

nervousness

nightmares

seizures

shakiness

slurred speech

unusual drowsiness, dullness, tiredness, weakness, or feeling of sluggishness

Some 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. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

Discouragement

feeling sad or empty

irritability

lack of appetite

loss of interest or pleasure

trouble concentrating

trouble sleeping

Less common

Diarrhea

dream activity

feeling of constant movement of self or surroundings

sensation of spinning

sleepiness

Incidence not determined

Decreased interest in sexual intercourse

dry mouth

inability to have or keep an erection

loss in sexual ability, desire, drive, or performance

loss of hair, temporary

pain of penis on erection

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

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

It is very important that your doctor check your progress at regular visits to make sure this medicine is working properly and to check for unwanted effects .

Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. If you think you have become pregnant while using the medicine, tell your doctor right away .

Make sure any doctor or dentist who treats you knows that you are using this medicine. You may need to stop using this medicine several days before having surgery .

Atenolol may cause heart failure in some patients. Check with your doctor right away if you are having chest pain or discomfort; dilated neck veins; extreme fatigue; irregular breathing; an irregular heartbeat; shortness of breath; swelling of the face, fingers, feet, or lower legs; weight gain; or wheezing .

This medicine may cause changes in your blood sugar levels. Also, this medicine may cover up signs of low blood sugar, such as a rapid pulse rate. Check with your doctor if you have these problems or if you notice a change in the results of your blood or urine sugar tests .

This medicine may cause some people to become less alert than they are normally. If this side effect occurs, do not drive, use machines, or do anything else that could be dangerous if you are not alert while taking atenolol .