Penbutolol is used to treat high blood pressure. Penbutolol is in a class of medications called beta blockers. It works by relaxing blood vessels and slowing heart rate to improve blood flow and decrease blood pressure.

Penbutolol comes as a tablet to take by mouth. It is usually taken once a day. Follow the directions on your prescription label carefully and ask your doctor or pharmacist to explain any part you do not understand. Take penbutolol exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Penbutolol helps control your condition but will not cure it. Continue to take penbutolol even if you feel well. Do not stop taking penbutolol without talking to your doctor.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Before taking penbutolol,

• Tell your doctor and pharmacist if you are allergic to penbutolol or any other drugs.
• Tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially medications for migraine headaches, asthma, allergies, colds, or pain; other medications for heart disease or high blood pressure; reserpine (Serpasil); and vitamins.
• Tell your doctor if you have or have ever had asthma; diabetes; heart block; an overactive thyroid; or heart, lung, liver, or kidney disease.
• Tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking penbutolol, call your doctor.
• If you are having surgery, including dental surgery, tell your doctor or dentist that you take penbutolol.

Unless your doctor tells you otherwise, continue your normal diet.

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

Penbutolol may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• Upset stomach
• Diarrhea
• Cough
• Dizziness or lightheadedness
• Excessive tiredness
• Headache
• Difficulty sleeping
• Sweating
• Decreased sexual ability
• Memory loss

If you experience any of the following symptoms, call your doctor immediately:

• Chest pain
• Difficulty breathing or swallowing
• Fainting
• Slow or irregular heartbeat
• Depression
• Easy bruising or bleeding

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA’s Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can’t be awakened, immediately call emergency services at 911.

Keep all appointments with your doctor and the laboratory.

Your blood pressure should be checked regularly to determine your response to penbutolol. Your doctor may ask you to check your pulse (heart rate). Ask your pharmacist or doctor to teach you how to take your pulse. If your pulse is faster or slower than it should be, call your doctor.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.