© 2014 The British Pharmacological Society. β-adrenoceptor blockers have an important role in the treatment of heart disease and are useful as an adjunct in systemic hypertension. They are often prescribed at unnecessarily high doses, near the top of the dose-response curve. Higher doses are associated with more adverse events, have not been shown to improve clinical outcomes in cardiac failure and may worsen outcome in hypertension. β-adrenoceptor blockers can be very effective in lower doses, guided by close monitoring of heart rate and blood pressure and, when used in combination with low dose vasodilators and diuretics, give a better risk benefit profile.