Beta-blockers
Labetalol
A beta-blocker that lowers blood pressure and is one of the preferred options in pregnancy; it should not be stopped suddenly.
What is Labetalol?
Labetalol is a beta-blocker used to lower high blood pressure, including high blood pressure in pregnancy, where it is one of the preferred medicines. It slows the heart and relaxes blood vessels, which together bring blood pressure down. It is taken regularly and should not be stopped suddenly, as this can cause a rebound rise in blood pressure or heart symptoms.
Education and reference only. This is a plain-language guide to Labetalol — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Labetalol is a beta-blocker prescribed in the UK to treat high blood pressure. Unlike many beta-blockers it has an added effect of relaxing blood vessels, which makes it particularly useful, and it is one of the first-choice medicines for high blood pressure during pregnancy. It is taken regularly as a long-term medicine to keep blood pressure controlled, and the benefit is measured in lower cardiovascular risk over time rather than in how you feel from day to day.
How it works
Labetalol blocks beta receptors, which slows the heart and reduces the force of each heartbeat, and it also blocks alpha receptors, which relaxes and widens blood vessels. The combination lowers blood pressure more smoothly than blocking the heart alone. Because it acts on the heart and circulation, it can also cause some of its main side effects, such as tiredness and dizziness when standing up.
Company & origin
Originated / developed by: Originally developed by Glaxo (now part of GSK)..
Labetalol was developed in the 1970s and introduced in the UK as Trandate. It is unusual among beta-blockers in also relaxing blood vessels, and is now widely used to treat high blood pressure, including during pregnancy.
What it treats
Conditions Labetalol is used for
Practical use
How to take Labetalol
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take it regularly as prescribed to keep your blood pressure controlled, even on days you feel well.
- Take it with food, which helps it be absorbed and can reduce light-headedness.
- Stand up slowly, especially when you first start, as it can cause dizziness when getting up.
- If you have diabetes, be aware it can hide some warning signs of a low blood sugar, such as a racing heart.
- If you miss a dose, take it as soon as you remember unless it is nearly time for the next one — do not double up.
- Never stop it suddenly; speak to your prescriber, who will reduce it gradually if it needs to be stopped.
Weighing it up
Advantages & disadvantages of Labetalol
Advantages
- It is one of the preferred medicines for high blood pressure in pregnancy, where many other options are avoided.
- It both slows the heart and relaxes blood vessels, giving smooth blood-pressure lowering.
- It is well established, widely used and available in a form that can be given in hospital when blood pressure needs lowering more quickly.
Disadvantages
- It must never be stopped suddenly, as this can cause a rebound rise in blood pressure or heart symptoms.
- It can cause tiredness and dizziness, particularly when standing, which some people find limiting.
- In people with diabetes it can mask some warning signs of a low blood sugar.
- It is usually taken more than once a day, which some people find less convenient.
Practical use
Good to know
Labetalol is taken regularly to keep blood pressure controlled rather than only when you feel unwell. It is best taken with food, which helps absorption and reduces dizziness. It can cause light-headedness, particularly when standing up quickly, so rise slowly at first. In people with diabetes it can mask some of the warning signs of a low blood sugar, such as a fast heartbeat. It must never be stopped suddenly, as abrupt stopping can cause a rebound rise in blood pressure or chest symptoms; any change is made gradually under medical advice.
Who should not take it / use with caution
- People with asthma or certain other breathing problems, in whom beta-blockers can trigger wheeze.
- People with a very slow heart rate, certain heart rhythm or conduction problems, or untreated heart failure.
- People with very low blood pressure or severe circulation problems, used with caution.
Monitoring
- Regular blood-pressure checks to see how well it is working.
- Checking heart rate and watching for excessive tiredness or dizziness.
- In pregnancy, monitoring of blood pressure and the baby as part of routine antenatal care.
Side effects
- Tiredness and dizziness, especially when starting.
- Light-headedness when standing up quickly (postural dizziness).
- Cold hands and feet, headache or a blocked nose.
- Occasionally a slow heart rate, or masking of low-blood-sugar warning signs in people with diabetes.
- Rarely it can affect the liver — tell your prescriber promptly if you develop unexplained nausea, dark urine or yellowing of the skin or eyes.
Key interactions
- Other blood-pressure-lowering medicines add to its effect and can cause dizziness or low blood pressure.
- Some heart-rate-slowing medicines, such as certain calcium-channel blockers (verapamil or diltiazem), can slow the heart too much.
- Medicines for diabetes, because labetalol can mask warning signs of a low blood sugar.
Available as: Tablets, and an injection used in hospital.
Answers
Labetalol: frequently asked questions
Can I take labetalol in pregnancy?
Yes — labetalol is one of the preferred medicines for high blood pressure in pregnancy in the UK. If you are pregnant or planning a pregnancy, your blood pressure and the baby will be monitored as part of your antenatal care.
Can I stop labetalol if my blood pressure is fine?
No — do not stop it suddenly. Stopping abruptly can cause a rebound rise in blood pressure or heart symptoms. If you want to stop, speak to your prescriber, who will reduce it gradually.
Why should I take labetalol with food?
Taking it with food helps it be absorbed properly and can reduce light-headedness. Try to take it in a consistent way each day.
Does labetalol affect diabetes?
It can mask some warning signs of a low blood sugar, such as a fast or pounding heartbeat. If you have diabetes, be alert to other signs like sweating and check your blood sugar if you feel unwell.
Why do I feel dizzy when I stand up?
Labetalol can cause a drop in blood pressure on standing, especially when you first start. Rise slowly from sitting or lying, and tell your prescriber if the dizziness is troublesome.
The wider class
About Beta-blockers
Labetalol belongs to the beta-blockers class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
Browse by body system
Authoritative sources
- BNF
- NICE CKS
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