Blood pressure medication is among the most widely prescribed drugs in the UK, taken by around nine million Britons, yet studies show almost half of patients fail to take their tablets regularly and around a fifth do not take them at all. A key reason is unpleasant side effects, including swollen ankles, chronic coughing and frequent need to urinate, which have led some patients to abandon their medication altogether despite the drugs' proven ability to reduce heart attack and stroke risk. Experts warn this is concerning because high blood pressure itself causes no symptoms, meaning patients may not appreciate the long-term danger of stopping treatment.

Following a column by GP Dr Ellie Cannon, dozens of readers wrote in describing their experiences, including an 82-year-old man with swollen ankles and diarrhoea, a 62-year-old woman with a constant "frog in her throat" cough, and a 74-year-old man needing the toilet frequently. Professor Amitava Banerjee of University College London says that while the drugs are life-saving, lifestyle changes can in some cases lower blood pressure enough to allow patients to stop medication safely, though others will need to remain on tablets indefinitely. Blood pressure readings consistently above 140/90 are classed as high, compared with a normal reading of around 120/80, and a recent Israeli study also linked one class of these drugs, calcium-channel blockers, to a heightened risk of kidney disease.