Over-the-counter, or OTC, medications play an important role in treating everything from acne to pain. However, in some cases an OTC medication can cause more symptoms than it treats, especially if you are allergic to an active ingredient in the medication. The results may even be deadly, depending on how severe your body reacts.
Allergen Basics
Allergies are a common part of life for many people; an estimated 40 to 50 million Americans struggle with some form of allergy, according to American Academy of Allergy, Asthma and Immunology. An allergy occurs when your body mistakes something that is harmless as harmful to the body. This causes your body to mount an allergic response to the substance, resulting in several changes in the body that produce the common symptoms of allergies.
Role of Histamine
Many of the symptoms seen with an allergy to OTC medications revolve around histamine. When the offending ingredient in a medication comes into contact with your body's lymphocytes, the mast cell of the lymphocyte is triggered, causing the release of histamine in the area that has come into contact with the drug. Histamine then triggers symptoms like inflammation as the histamine increases the permeability of vessels in the exposed area, resulting in blood fluids building in the area and causing swelling. When the swelling is localized in small areas, this results in hives.
Mild Symptoms
Beyond just swelling, an allergic reaction can cause a wide range of mild symptoms, which can include itchy skin, tingling mouth, congestion, runny nose and itchy or watery eyes. These effects are typically short-lived and are not typically dangerous. However, they do help alert you to an allergy so you can avoid using the medication in the future.
When to Call a Doctor
Allergic reactions to over-the-counter medications are not always mild. In fact, allergies can quickly become life threatening, depending on the symptoms. The symptoms that warrant calling your doctor or 911 -- depending on severity -- include wheezing; swelling of the tongue, face or throat; difficulty breathing; rapid and weak pulse; severe skin rash; nausea; vomiting; lightheadedness; and loss of consciousness. These symptoms can be the start of anaphylaxis, which can cause you to go into shock and die.
