Ask The Doc

for February 10, 2001

Q: I recently had a severe reaction to Augmentin and had to go to the hospital where I was given Benadryl and cortisone intravenously. My doctor tells me that I now have "serum sickness." I have joint pain and fatigue as well as headaches. What exactly is "serum sickness?"

A:

"Serum sickness" is a severe allergic and immune reaction to a foreign protein. It was initially described after serum (the clear portion of blood that remains after it has been allowed to clot) from one person was transfused or injected into another person. In modern times, reactions to antibiotic medications or vaccinations are more common causes.

The illness occurs because the immune response directed against foreign proteins is so dramatic that it causes significant inflammation and damage, in the same way that "friendly fire" in a military battle can cause injury to one's own troops. Symptoms include fever, joint pain, fluid retention in the arms and legs, enlarged lymph nodes and hives.

In contrast to the more immediate allergic reactions to medications or insect bites, serum sickness typically occurs six to 12 days after exposure, presumably because it takes that long for the body to make antibodies directed against the foreign protein.

Treatment is supportive: removing the offending agent (such as a medication), reducing fever with acetaminophen, reducing pain with anti-inflammatory agents (such as ibuprofen or even corticosteroids) and waiting for the reaction to resolve. Antihistamines such as Benadryl may reduce or shorten the duration of allergic symptoms such as hives. With prompt recognition and supportive care, serum sickness rarely causes long-term problems.

If your reaction was within a day or two of taking Augmentin, your reaction might be related to a more common form of allergic reaction in which the body's immune system reacts right away without having to synthesize new antibodies.

Severe forms (often called anaphylaxis or, if the blood pressure is low, anaphylactic shock) require emergency care to prevent serious illness or even death. The good news is that after an episode of serum sickness or a more immediate allergic reaction to a medication, chronic headaches, fatigue and joint pain would not be expected.

February 10, 2001

Robert H. Shmerling, M.D., is associate physician at Beth Israel Deaconess Hospital and associate professor at Harvard Medical School. He has been a practicing primary care physician and rheumatologist for 17 years at Beth Israel Deaconess Medical Center. He is an active teacher in the Internal Medicine Residency Program serving as the Robinson Firm Chief. He is also a teacher in the Rheumatology Fellowship Program. In 1997, he was awarded the Hermann Blumgart teaching award which honors the best teacher in the medical residency program.

To ask a question of our team of experts, just visit the Ask The Doc area on the InteliHealth Web page.

All information is intended for your general knowledge only and is not a substitute for medical advice or treatment for specific medical conditions. You should seek prompt medical care for any specific health issues and consult your physician before starting a new fitness regimen.