What is Tenormin?

Tenormin is in a group of drugs called beta-blockers. Beta-blockers affect the heart and circulation (blood flow through arteries and veins).

Tenormin is used to treat angina (chest pain) and hypertension (high blood pressure). It is also used to treat or prevent heart attack.

Tenormin may also be used for purposes other than those listed in this medication guide.

Important information

Do not stop taking Tenormin without first talking to your doctor. Stopping suddenly may make your condition worse.

If you need to have any type of surgery, you may need to temporarily stop using Tenormin. Be sure the surgeon knows ahead of time that you are using Tenormin.
Tenormin can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert. Avoid drinking alcohol, which could increase drowsiness and dizziness while you are taking Tenormin.

Tenormin is only part of a complete program of treatment for hypertension that may also include diet, exercise, and weight control. Follow your diet, medication, and exercise routines very closely if you are being treated for hypertension.

Hypertension often has no symptoms, so you may not even feel that you have high blood pressure. Continue using this medicine as directed, even if you feel well. You may need to use blood pressure medication for the rest of your life.

Before taking this medicine

You should not use Tenormin if you are allergic to atenolol, or if you have certain heart conditions such as slow heartbeats, or heart block.

Before taking this medication, tell your doctor if you have:

asthma, bronchitis, emphysema;
diabetes;
low blood pressure;
a heart problem such as heart block, sick sinus syndrome, slow heart rate, or congestive heart failure;
depression;
liver or kidney disease;
a thyroid disorder;
myasthenia gravis;
pheochromocytoma; or
problems with circulation (such as Raynaud’s syndrome).

If you have any of these conditions, you may not be able to use Tenormin, or you may need a dosage adjustment or special tests during treatment.
FDA pregnancy category D. Tenormin can cause harm to an unborn baby. Do not use Tenormin if you are pregnant. Tell your doctor if you become pregnant during treatment. Use an effective form of birth control while you are using Tenormin. Tenormin can pass into breast milk and may harm a nursing baby. Do not use Tenormin without telling your doctor if you are breast-feeding a baby.

How should I take Tenormin?

Take Tenormin exactly as it was prescribed for you. Do not take the medication in larger amounts or for longer than recommended by your doctor.
Take this medication with a full glass of water.

Take Tenormin at the same time every day.
Do not skip doses or stop taking Tenormin without first talking to your doctor. Stopping suddenly may make your condition worse.

To be sure this medication is helping your condition, your blood pressure will need to be checked on a regular basis. It is important that you not miss any scheduled visits to your doctor.

If you need to have any type of surgery, tell the surgeon that you are using Tenormin. You may need to briefly stop using Tenormin before having surgery.

Tenormin is only part of a complete program of treatment for hypertension that may also include diet, exercise, and weight control. Follow your diet, medication, and exercise routines very closely if you are being treated for hypertension.

Hypertension often has no symptoms, so you may not even feel that you have high blood pressure. Continue using this medicine as directed, even if you feel well. You may need to use blood pressure medication for the rest of your life.
Store Tenormin at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. If your next dose is less than 8 hours away, skip the missed dose and take the medicine at the next regularly scheduled time. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention if you think you have used too much of this medicine.

Symptoms of an Tenormin overdose may include uneven heartbeats, shortness of breath, bluish-colored fingernails, dizziness, weakness, fainting, or seizure (convulsions).

What should I avoid?

Tenormin can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert. Avoid drinking alcohol, which could increase drowsiness and dizziness while you are taking Tenormin.

Tenormin side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Call your doctor at once if you have any of these serious side effects:

slow or uneven heartbeats;
feeling light-headed, fainting;
feeling short of breath, even with mild exertion;
swelling of your ankles or feet;
nausea, stomach pain, low fever, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);
depression; or
cold feeling in your hands and feet.

Less serious Tenormin side effects may include:

decreased sex drive, impotence, or difficulty having an orgasm;
sleep problems (insomnia);
tired feeling; or
anxiety, nervousness.

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

What other drugs will affect Tenormin?

Before taking Tenormin, tell your doctor if you are using:

allergy treatments (or if you are undergoing allergy skin-testing);
amiodarone (Cordarone, Pacerone);
clonidine (Catapres);
digoxin (digitalis, Lanoxin);
disopyramide (Norpace);
guanabenz (Wytensin);
an MAO inhibitor such as isocarboxazid (Marplan), tranylcypromine (Parnate), phenelzine (Nardil), or selegiline (Eldepryl, Emsam);
a diabetes medication such as insulin, glyburide (Diabeta, Micronase, Glynase), glipizide (Glucotrol), chlorpropamide (Diabinese), or metformin (Glucophage);
a heart medication such as nifedipine (Procardia, Adalat), reserpine (Serpasil), verapamil (Calan, Verelan, Isoptin), diltiazem (Cartia, Cardizem);
medicine for asthma or other breathing disorders, such as albuterol (Ventolin, Proventil), bitolterol (Tornalate), metaproterenol (Alupent), pirbuterol (Maxair), terbutaline (Brethaire, Brethine, Bricanyl), and theophylline (Theo-Dur, Theolair); or
cold medicines, stimulant medicines, or diet pills.

If you are using any of these drugs, you may not be able to take Tenormin, or you may need dosage adjustments or special tests during treatment.

There may be other drugs not listed that can affect Tenormin. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.