Atenolol is a widely prescribed medication used to manage various health conditions, including high blood pressure and irregular heart rhythms. While the beta-blocker drug is generally safe for most adults, certain people need to be cautious before taking it.

The NHS advises that this particularly applies to six main groups with specific diagnoses or symptoms. This includes those with low blood pressure, Raynaud's disease, or asthma, who should consult a doctor before starting atenolol.

Other groups who should seek medical advice before taking atenolol include:

• People who are trying to get pregnant, are already pregnant or breastfeeding
• People who have Raynaud's phenomenon, which may make their fingers and toes tingle, turn paler than usual or turn blue
• People who have metabolic acidosis – when there's too much acid in your blood
• People who have low blood pressure (hypotension) or a slow heart rate
• People who have lung disease or asthma
• People who have ever had an allergic reaction to atenolol or any other medicine

Official NHS guidance explains: "Atenolol works by slowing down your heart rate, making it easier for your heart to pump blood around your body. Atenolol is sometimes prescribed to prevent migraines and help with anxiety.

"This medicine is only available on prescription. It comes as tablets or as a liquid that you swallow. It can also be given as an injection, but this is usually done in hospital."

Additionally, anyone taking other medications should seek medical advice before using atenolol, as it could impact the drug's effectiveness. This encompasses herbal treatments, vitamins and supplements, alongside:

• Other medicines for high blood pressure – the combination with atenolol can sometimes lower your blood pressure too much, which may make you feel dizzy or faint
• Other medicines for an irregular heartbeat (arrhythmia), such as amiodarone or flecainide
• Medicines for asthma or chronic obstructive pulmonary disease (COPD)
• Medicines for diabetes, particularly insulin – atenolol may make it more difficult to recognise the warning signs of low blood sugar. Speak to your doctor if you have low blood sugar levels without getting any of the usual warning signs. Check your blood sugar after exercise and follow the usual advice about checking it before driving or operating machinery
• Medicines to treat nose or sinus congestion, or other cold remedies (including those you can buy in a pharmacy)
• Medicines for allergies, such as ephedrine, noradrenaline or adrenaline

NHS guidance adds: "There's not enough information to say that herbal remedies and supplements are safe to take with atenolol. They're not tested in the same way as pharmacy and prescription medicines. They're generally not tested for the effect they have on other medicines."

The precise dosage of atenolol required depends on your specific condition. While the standard adult dose for hypertension typically falls between 25mg and 50mg daily, it's crucial to adhere to your doctor's advice. Instructions will also be provided on your medication packaging.

The duration of treatment with atenolol is determined by the purpose of its use. For conditions such as high blood pressure, atenolol is typically prescribed for an extended period, potentially for a lifetime.

For more information, head to the NHS website here.