Beta blockers are a group of medicines that slow your heart rate and lower your blood pressure, making it easier for your heart to pump blood. They are used to treat a variety of conditions such as to:
Sometimes a medicine isn’t suitable for a person with certain conditions, or it can only be used with extra care. It’s important that you tell your doctor or pharmacist before you start using beta blockers if you have:
asthma or COPD
low blood pressure
very slow heart rate.
How to take beta blockers
When you first starting taking a beta blocker, your doctor will start you on a low dose then slowly increase it over the next few weeks. It can take a while for you to feel better — usually a few months. Do not suddenly stop taking your beta blocker without talking to your doctor first. This can be dangerous and make you feel unwell. You may get the feeling of changes in your heart beat (fast, quick and irregular or forceful heartbeats), an increase in blood pressure and a return of chest pains. If you do need to stop taking a beta-blocker then your doctor may advise a gradual reduction in dose.
Possible side effects
When you first start taking a beta blocker or get your dose increased you may feel tired or have other side effects for a few days. These side effects usually slowly go away with time.
What should I do?
These are quite common when you first start taking a beta blocker, and usually go away with time.
cold hands and feet
rash or itching
constipation or diarrhoea
depression and low mood
nightmares or sleep problems
Tell your doctor if they do not go away or are troublesome for you.
If you get any of these symptoms:
problems breathing such as chest tightness or wheezing
swelling of the feet or legs
feel like fainting
changes in heart rate (fast, slow or irregular)
allergic reaction such as skin rashes or itching
Tell your doctor immediately or ring HealthLine 0800 611 116.
Credits: Editorial team.
Last reviewed: 30 May 2014
Information for clinicians
This section will be of most interest to clinicians (eg, nurses, doctors, pharmacists and specialists).
Guide for initiation and up-titration of beta-blockers for patients with heart failure (SafeRx, March 2017)
If initiating a beta-blocker
Start only if:
Heart failure has stabilised and there are no more symptoms of worsening heart failure such as paroxysmal nocturnal dyspnoea.
No symptomatic bradycardia, hypotension or heart block.
Start with low dose
metoprolol 23.75 mg daily
carvedilol 3.125 mg twice daily
bisoprolol 1.25 mg daily
When up-titrating dose
The dose may be doubled every 2 weeks (some people may require a slower titration)
Beta-blockers can trigger bronchospasm and should therefore usually be avoided in patients with an established history of asthma. In the absence of a suitable alternative, it may be necessary for a patient with well-controlled asthma, or COPD (without significant reversible airways obstruction), to receive treatment with a beta-blocker for a co-existing condition (e.g. heart failure or following myocardial infarction).
In this situation, a cardioselective beta-blocker should be selected and initiated at a low dose by a specialist; the patient should be closely monitored for adverse effects.
Atenolol, bisoprolol, and metoprolol have less effect on the beta2 (bronchial) receptors and are, therefore, relatively cardioselective, but they are not cardiospecific. They have a lesser effect on airways resistance but are not free of this adverse effect.
Beta-blockers can affect carbohydrate metabolism, causing hypoglycaemia or hyperglycaemia in patients with or without diabetes; they can also interfere with metabolic and autonomic responses to hypoglycaemia, thereby masking symptoms such as tachycardia. However, beta-blockers are not contra-indicated in diabetes, although the cardioselective beta-blockers (see above) may be preferred.
Avoid beta-blockers in patients with frequent episodes of hypoglycaemia.
Beta-blockers, especially when combined with a thiazide diuretic, should be avoided for the routine treatment of uncomplicated hypertension in patients with diabetes or in those at high risk of developing diabetes.