Health authorities are issuing updated warnings about a potentially dangerous side effect associated with widely prescribed ACE inhibitors, a class of drugs used to treat high blood pressure and heart conditions. The side effect, known as angioedema, can manifest weeks, months, or even years after a patient begins taking the medication.
ACE inhibitors, including medications such as ramipril, lisinopril, enalapril, and perindopril, are commonly prescribed for conditions including hypertension, heart failure, post-heart attack recovery, diabetic kidney disease, and the prevention of cardiovascular issues.
The patient information leaflets for these drugs are being updated to strengthen warnings regarding the risk of delayed-onset angioedema. This condition causes swelling in the deeper layers of the skin or tissues lining parts of the body. While angioedema can be triggered by an allergic reaction involving histamine, a significant concern with ACE inhibitors is the bradykinin-related form. This type typically develops without itching or hives and can progress more slowly, leading to swelling of the lips, tongue, face, or throat.
Both forms of angioedema can be life-threatening if the swelling obstructs the airway. The Medicines and Healthcare products Regulatory Agency (MHRA) in the UK issued the updated guidance after reviewing reports submitted through its Yellow Card scheme. The review indicated that approximately half of the cases with a recorded onset time developed at least 30 days after treatment began. Manufacturers' data suggests that 20% to 30% of reported cases occurred after patients had taken the medicine for a month or longer.
Distinguishing Between Angioedema Types
Health chiefs emphasize the importance of distinguishing between bradykinin-mediated and histamine-mediated angioedema, as treatment strategies differ significantly. Bradykinin-related angioedema does not typically respond to standard treatments for severe allergic reactions, such as adrenaline. Healthcare professionals, particularly in emergency departments, are urged to be aware of the potential for delayed angioedema and to consider the bradykinin-related form when usual treatments are ineffective.
While fatal cases of ACE inhibitor-related angioedema are rare, they have occurred when swelling blocked the airway, sometimes in patients who had been taking the medication for an extended period. Published research has documented cases developing anywhere from several weeks to many years after treatment initiation.
Certain individuals may face a higher risk of ACE inhibitor-related angioedema, including older adults, women, smokers, and people of Black or African-Caribbean heritage. Anyone experiencing symptoms suggestive of angioedema while taking an ACE inhibitor should discontinue the medication immediately and must not restart it. Ramipril is noted as one of the most commonly prescribed ACE inhibitors in the UK, with millions of prescriptions issued annually.