Final answer:
Beta-blockers are contraindicated in diabetics because they can mask the symptoms of low blood sugar and impair blood sugar control.
Step-by-step explanation:
Beta-blockers are contraindicated in diabetics because they can mask the symptoms of low blood sugar (hypoglycemia). These medications block the beta receptors in the body, which can prevent the normal response to low blood sugar, such as increased heart rate and palpitations. This makes it more difficult for diabetics to recognize and treat hypoglycemia.
Additionally, beta-blockers can also impair the release of insulin from the pancreas and increase insulin resistance, which can further worsen blood sugar control in diabetics.