Angioedema is swelling beneath the skin caused by an allergic reaction, medication side effect, or hereditary condition. Common triggers include foods (nuts, shellfish), insect stings, and drugs such as ACE inhibitors or antibiotics. The immune system releases histamine and other chemicals, leading to sudden swelling in areas like the face, lips, tongue, or throat, which can become life-threatening. Prevention involves identifying and avoiding known triggers, carrying prescribed emergency medications, and consulting a doctor before starting new treatments. If you’re sourcing medications, ensure quality and reliability by working with a trusted cephalexin capsules supplier to minimize risks of adverse reactions.