Doctor Decoded: What Are Autoimmune Diseases?

You’ve been having weird symptoms that come and go, and your doctor has been searching for an answer. Finally, they say you have an autoimmune disease. Huh?

Autoimmune diseases are diseases of the immune system. The prefix auto- literally means “self.” In other words, the immune system is attacking oneself.

How a healthy immune system works

A healthy immune system is in charge of protecting your body against threats like viruses, bacteria, parasites, cancer cells, etc. When the immune system detects a threat, it sends immune cells to attack. This helps to get rid of the invaders, but it also creates inflammation in the area.

Inflammation isn’t necessarily a bad thing, but it does cause redness, swelling, stiffness, or pain. That’s what causes you to get stuffed up when you have a cold, or a sore throat when you get strep. These are examples of acute inflammation, meaning it’s temporary.

When the immune system goes awry

An autoimmune disease means the immune system is mistakenly attacking the body’s own, healthy tissue. This results in chronic inflammation, meaning it’s long-term, low-grade pain and swelling. Learn more about the difference between acute and chronic inflammation.

There are more than 100 types of autoimmune diseases, and they tend to attack a specific organ. Some of the most common types of autoimmune diseases include:

• Rheumatoid arthritis: Immune cells attack joint tissue, resulting in swollen and painful fingers, hands, and feet.

• Inflammatory bowel disease: This affects the digestive tract, and it includes Crohn’s disease and ulcerative colitis.

• Psoriasis: Immune cells attack the skin, resulting in patches of red, scaly skin.

• Alopecia: This is when immune cells attack the hair follicles, causing the hair to fall out.

• Celiac disease: Immune cells attack the small intestine, but only when gluten is present.

Living with an autoimmune disease

Unfortunately, there’s no cure for autoimmune diseases. However, many can be managed well with lifestyle changes and medications. Lifestyle changes may involve avoiding triggers (such as gluten, in the case of celiac disease), managing stress levels, and eating an anti-inflammatory diet.

Got more questions about disease lingo?

• Find out the difference between diseases and syndromes.

• Check out the difference between infectious and contagious.

• Find out the difference between genetic and hereditary diseases.

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Written by:

Lauren Smith, MA

Lauren Smith, MA, has worked in health journalism since 2017. Before joining GoodRx, she was the senior health editor and writer for HealthiNation.

Reviewed by:

Mera Goodman, MD, FAAP

Dr. Mera Goodman is a board-certified pediatrician. Prior to medicine, she worked as a management consultant.

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