Churg-Strauss syndrome is a disorder marked by blood vessel inflammation. This inflammation can restrict blood flow to organs and tissues, sometimes permanently damaging them. This condition is also known as eosinophilic granulomatosis with polyangiitis (EGPA). Adult-onset asthma is the most common sign of Churg-Strauss syndrome. The disorder can also cause other problems, such as nasal allergies, sinus problems, rash, gastrointestinal …

Alpha-gal syndrome (AGS) is a serious and unusual food allergy to red (mammalian) meat. It occurs in people who have been bitten by certain types of ticks, usually if they’ve been bitten more than once. Ticks are mite-like parasites that feed on blood. The saliva of some ticks contains a sugar molecule called alpha-gal (α-Gal). When alpha-gal enters the bloodstream, it can …

Allergic rhinitis (hay fever) is an allergic reaction to tiny particles in the air called allergens. When you breathe in allergens through your nose or mouth, your body reacts by releasing a natural chemical called histamine. Despite being called hay fever, hay doesn’t cause hay fever and most people don’t get a fever. Symptoms of hay fever include sneezing, nasal congestion and irritation …

ALS, or amyotrophic lateral sclerosis, is a neurodegenerative condition that affects the nerve cells (neurons) in your brain and spinal cord. It targets your motor neurons. These regulate voluntary muscle movements (like the ones you use to talk, chew and move your arms and legs) and breathing. Your neurons communicate with your muscles to tell them to move. ALS disrupts the communication, like bad phone reception. The …

Allergies are your body’s reaction to a foreign protein. Usually, these proteins (allergens) are harmless. However, if you have an allergy to a particular protein, your body’s defense system (immune system) overreacts to its presence in your body. What is an allergic reaction? An allergic reaction is the way your body responds to an allergen. If you have allergies, the …

Dry socket (alveolar osteitis) can happen after tooth extraction. When your dentist or oral surgeon removes a tooth, a blood clot forms in the socket (a hole in the bone where your tooth was). Dry socket happens when that blood clot dislodges (moves) or doesn’t form at all. Without the clot, your bone and nerves become exposed, leading to pain and slower healing. How common is dry …

Ear barotrauma refers to damage to your ears that can happen if there’s a sudden change in air pressure or water pressure that affects your middle ear. Some people call ear barotrauma “airplane ear” because it often affects people when they fly in an airplane. But people can also develop ear barotrauma riding in an elevator, diving to the bottom of …

Guillain-Barré syndrome (pronounced “ghee-AHN buh-RAY”) is a rare autoimmune condition in which your immune system attacks your peripheral nerves. It leads to symptoms like numbness, tingling and muscle weakness that can progress to paralysis. But with treatment, most people fully recover from the condition.

Age spots are small, flat dark areas on the skin. They vary in size and usually appear on areas exposed to the sun, such as the face, hands, shoulders and arms. Age spots are also called sunspots, liver spots and solar lentigines. Age spots are very common in adults older than 50, but younger people can get them if they …

Dry macular degeneration is an eye condition that causes blurred vision or reduced central vision. It is caused by the breakdown of a part of the retina known as the macula (MAK-u-luh). The macula is responsible for central vision. This condition is common among people over 50. Dry macular degeneration may start in one eye then develop in the other …