Penbutolol (Oral)

As a beta-blocker, Penbutolol can alter the responses to nerve impulses in your heart, which helps to eventually lower your blood pressure.


Penbutolol is a drug that can be given to patients suffering from hypertension (high blood pressure). It can be given alone or with other medicines, such as hydrochlorothiazide, which is a diuretic. It is important that you treat hypertension as it can lead to strokes, kidney failure, or heart failure. This is because long-term workload on your arteries and heart can cause your heart and arteries to no longer function properly. If controlled, you are at lower risk of such complications.

Penbutolol is a beta-blocker, which means it works by altering the responses to nerve impulses in different parts of your body, in this case, the heart. In turn, your heart is able to beat slower and decrease your blood pressure, which means more oxygen and blood can make its way to the heart. You can only obtain this medicine with a doctor's prescription.

Condition(s) treated

  • Hypertension

Type of medicine

  • Tablet

Side Effects

As well as helping to treat hypertension, certain side effects may occur. If you experience any of the side effects listed directly below, you should contact your doctor immediately.

Less common

  • Tightness in the chest

Incidence not known

  • White spots, sores, or ulcers in the mouth or on the lips

Symptoms of overdose

  • Dilated neck veins

As well as these more serious side effects, you could experience less serious ones which don't require emergency attention. Directly below is a list of such effects You may find that the effects wear off over time as your body adjusts to the medicine. However, if they are lingering or worrying you, then you can still contact your doctor for guidance on how to proceed and possibly reduce them.

More common

Less common

  • Ear congestion


  • Inability to keep or have an erection

Incidence not known

  • Dysphoria

As well as those listed above, it is possible that you will experience other side effects. If this is the case, then you can still contact our doctor and discuss them.


Below you can find the typical doses of Penbutolol that is given to patients suffering from hypertension. Be aware that your dosage may differ, and this is because they are based on the extent of your condition, as well as other factors, such as other drugs you currently take. Do not change your doses or their frequency in any way, unless told to do so by your doctor.

  • Adults. To start, take 20mg once per day. This may then be altered when needed.

If you miss a dose of this drug for any reason, take it as soon as you remember. However, if it is almost time for you to take your next dose, simply skip the missed one and return to your doses as scheduled. This is because it is important you do not double dose.

As well as taking this drug, your doctor may well advise other dietary and lifestyle adjustments you should make. This includes changes in what you eat, notably foods with a lot of salt, as well as weight control. Your doctor will advise on the most important steps to take, and you should check with your doctor first before making any other dietary changes.

You should continue your appointments and doses as prescribed by your doctor, even if you feel fine. This is because many people have high blood pressure without even realizing it.

This medicine is not designed to cure high blood pressure. Instead, it helps to control. In order to keep your blood pressure down, you should take the medicine as prescribed. You may then need to do this for your entire life. Failure to do so could cause serious problems, such as kidney disease, heart failure, a stroke, and blood vessel disease.

You can take Penbutolol either with or without food.


It is possible that Penbutolol will interact with other drugs you currently take. You should, therefore, advise your doctor of all prescription and nonprescription drugs you are taking. Directly below is a list of drugs with which it is usually not recommended you take at the same time as Penbutolol. If it is necessary for you to take both, your doctor may alter the doses of one or both of the medicines.

  • Fingolimod

If you take any of the following drugs with Penbutolol, it could cause an increased chance of experiencing some side effects. However, again it may be best for you to take both, so your doctor may adjust your prescription.

  • Insulin Degludec

As well as interacting with drugs, Penbutolol could interact with aspects of your dietary intake. Your doctor may advise you may changes to what you eat, drink, or smoke.

Finally, other medical problems you have may interact with Penbutolol. Be careful in telling your doctor if you have any of the following.

  • Blood vessel or heart disease (such as coronary artery disease). Take this medicine with caution as it could make this condition worse


Before prescribing you this medicine, your doctor will need to ensure it is appropriate for your medical condition. In assessing this suitability, they will also need to be aware of any allergies you currently suffer from, which includes allergies to animals, dyes, foods, and preservatives.

As of writing, no safety and efficacy have been established for the use of Penbutolol in pediatric patients. This is because suitable studies have not yet been performed.

The studies that have taken place in older patients using Penbutolol have not highlighted any problems that would make this drug less useful for geriatric patients. However, you should be aware that geriatric patients are more likely to suffer from age-related heart, kidney, and liver problems. This could mean that the dosage of Penbutolol will need to be adjusted.

As of writing, it is unclear as to whether suitable studies have taken place on pregnant women, and whether any harmful effects have been studied. Your doctor can advise you on whether this is a safe and suitable drug to take when pregnant. If, whilst taking this medicine, you become pregnant, you should inform your doctor immediately.

Similarly, there are no appropriate studies into the effects of Penbutolol on breastfeeding women. Together with your doctor, you can weigh any increased risks against the benefits it offers.

Whilst taking Penbutolol, your doctor will want to see you during regular appointments. It is important you attend these so they can check for any unwanted side effects.

Taking Penbutolol does have the potential to cause heart failure. If you experience any of the following symptoms at any time, inform your doctor immediately and stop taking the medicine.

  • Extreme fatigue

You should only ever interrupt this medicine or stop taking it if you have been told to do so by your doctor. Instead of stopping suddenly, they may want to gradually reduce your dose. Stopping suddenly may make the condition worse.

You may experience a severe allergic reaction known as anaphylaxis whilst taking this medicine. This reaction requires you to get emergency medical assistance as it is life-threatening. If you experience any of the following symptoms at any time, inform your doctor.

  • Trouble breathing

If you receive any other treatment from a doctor or dentist, inform them that you are taking this medicine. However, do not stop taking this medicine before having surgery, unless your doctor has told you to do so.

Penbutolol can cause fluctuations in your blood sugar levels. Also, it may cover up signs that you have low blood sugar; such as having a rapid pulse rate. If you do notice this problem, such as by changes in your urine or blood tests, then you should inform your doctor.

Unless they have been cleared by your doctor, do not take any other medicines at the same time as Penbutolol. This includes prescription and nonprescription drugs, as well as vitamin and herbal supplements.


You should store your Penbutolol in a sealed container and keep it safely away from children. It should be kept at room temperature, away from any direct light, moisture, or heat. It should not be allowed to freeze. If, after finishing your treatment, you have some medicine left, you should dispose of it. Similarly, you should dispose of any medicine that is out of date. If you have any questions regarding the safe and sensible way to do this then you should contact your doctor or pharmacist.


If you do currently suffer from hypertension, then it is vitally important that you seek an appropriate means to treat it. Penbutolol is one medication that can be an effective way to reduce your blood pressure and then keep it down. Though this will not cure your condition, it can allow you to avoid the risk of more serious complications that persistently high blood pressure leads to. However, you should be aware that this medicine is not suitable for everyone.

It can react with a number of other medicines and can lead to some worrying side effects. Above you can find full details regarding the potential side effects this medicine can cause. If you do suffer from any of the more serious ones, then you should consult with your doctor. They may need to alter your prescription to avoid further complications. Similarly, if you have any other questions regarding this medicine, they should be addressed to your healthcare professional.