If you suffer from allergies, you’re definitely not alone. More than 50 million Americans have allergies — the sixth leading cause of chronic disease in the United States.
Allergies are caused by a hypersensitive reaction of the immune system to a particular substance or substances (known as allergens) that are otherwise harmless to the majority of people. An allergic reaction can range from mildly inconvenient or intensely uncomfortable, to disabling or life-threatening.
How does your body respond to an allergen?
The immune system produces antibodies to defend against allergens. When antibodies are present in the body, histamine is automatically released into the bloodstream. Histamine is responsible for triggering inflammation throughout the body and causing smooth muscle contraction. For example, histamine is a key chemical involved in triggering an allergic asthma attack. It can cause key muscles surrounding the airways to contract, causing shortness of breath and difficulty breathing. The production of histamine is responsible for all the annoying allergic reactions that most people experience, such as a runny and/or stuffy nose, watery eyes, coughing, sneezing, wheezing, hives, rashes, and asthma.
Histamine production can also cause gastrointestinal inflammation leading to cramping, diarrhea, gas, and constipation. Life-threatening reactions can cause anaphlaxis, a medical emergency. Antihistamines are typically the first line of defense against allergic reactions.