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Generic Name: timolol (TIH mo lol)
Brand Name: Blocadren

What is timolol?

Timolol is a beta-blocker that affects the heart and circulation (blood flow through arteries and veins).

Timolol is used to treat hypertension (high blood pressure). Timolol is sometimes given with other blood pressure medication.

Timolol is also used to lower the risk of death after a heart attack, or to lower the risk of having another heart attack.

Timolol is also used to prevent migraine headaches.

Timolol may also be used for purposes not listed in this medication guide.

What is the most important information I should know about timolol?

You should not use this medicine if you have asthma or other breathing disorders, or a serious heart condition such as "AV block," very slow heartbeats, or heart failure.

What should I discuss with my healthcare provider before taking timolol?

You should not use timolol if you are allergic to it, or if you have:

  • asthma, chronic obstructive pulmonary disease (COPD), sleep apnea, or other breathing disorder;

  • a serious heart condition such as "AV block" (second or third degree);

  • very slow heartbeats; or

  • heart failure.

To make sure timolol is safe for you, tell your doctor if you have:

  • congestive heart failure;

  • coronary artery disease (hardened arteries);

  • diabetes;

  • overactive thyroid;

  • liver or kidney disease;

  • myasthenia gravis or other muscle disorders;

  • allergies (or if you are undergoing allergy treatments or skin-testing);

  • peripheral vascular disease such as Raynaud's syndrome; or

  • a condition for which you are being treated with IV heart or blood pressure medication (such as diltiazem, nicardipine, or verapamil).

It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

Timolol can pass into breast milk and may harm a nursing baby. You should not breast-feed while using this medicine.

Timolol is not approved for use by anyone younger than 18 years old.

How should I take timolol?

Follow all directions on your prescription label. Your doctor may occasionally change your dose to make sure you get the best results. Do not use this medicine in larger or smaller amounts or for longer than recommended.

Your blood pressure will need to be checked often.

If you need surgery, tell the surgeon ahead of time that you are using timolol. You may need to stop using the medicine for a short time.

You should not stop using timolol suddenly. Stopping suddenly may make your condition worse.

If you are being treated for high blood pressure: Keep using this medicine even if you feel well. High blood pressure often has no symptoms. You may need to use blood pressure medicine for the rest of your life.

If you are taking timolol to prevent migraine headaches: It may take 6 to 8 weeks of daily use before timolol is fully effective. Keep using the medication as directed and tell your doctor if you still have migraine headaches.

Store at room temperature away from moisture, heat, and light.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include slow heart rate, wheezing, trouble breathing, or fainting.

What should I avoid while taking timolol?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Timolol side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • new or worsening chest pain;

  • slow or uneven heartbeats;

  • a light-headed feeling, like you might pass out;

  • shortness of breath (even with mild exertion), swelling, rapid weight gain;

  • muscle weakness;

  • drooping eyelids, vision problems; or

  • a cold feeling in your hands and feet.

Common side effects may include:

  • trouble breathing;

  • dizziness;

  • nausea, upset stomach;

  • feeling tired; or

  • itching.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

Timolol dosing information

Usual Adult Dose for Hypertension:

Initial dose: 10 mg orally twice a day
Maintenance dose: 10 to 20 mg orally twice a day

Usual Adult Dose for Angina Pectoris:

Initial dose: 10 mg orally twice a day
Maintenance dose: 10 to 20 mg orally twice a day

Usual Adult Dose for Myocardial Infarction:

Initial dose: 10 mg orally twice a day

Usual Adult Dose for Migraine Prophylaxis:

Initial dose: 10 mg orally twice a day
Maintenance dose: 10 to 30 mg given in 1 to 2 divided doses

What other drugs will affect timolol?

Tell your doctor about all your current medicines and any you start or stop using, especially:

  • digoxin, digitalis;

  • heart or blood pressure medication--clonidine, diltiazem, nicardipine, nifedipine, reserpine, quinidine, verapamil, and others; or

  • NSAIDs (nonsteroidal anti-inflammatory drugs)--aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve), celecoxib, diclofenac, indomethacin, meloxicam, and others.

This list is not complete. Other drugs may interact with timolol, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Where can I get more information?

  • Your pharmacist can provide more information about timolol.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 9.01.

Date modified: October 14, 2016
Last reviewed: December 15, 2010