Serum sickness is the name for symptoms that result from a delayed immune system response, either to certain kinds of medications or to antiserum (given after a person has bitten by a snake or to counter exposure to rabies, for example). Serum is the clear fluid part of blood. Serum sickness is similar to an allergy, in that the body mistakenly identifies a protein from the antiserum or medication as harmful and activates the immune system to fight it off. Today, the most common cause of serum sickness is the antibiotic penicillin. Serum sickness will usually develop within 7 - 10 days after initial exposure, but sometimes it can take as long as 3 weeks. If you are exposed again to the substance, serum sickness tends to develop faster (within 1 -4 days), and only a very small amount of the substance may cause an intense response.

The first signs of serum sickness are redness and itching at the injection site. Other signs and symptoms include:

• Skin rash, hives
• Joint pain
• Fever
• Malaise (feeling unwell)
• Swollen lymph nodes
• Itching
• Wheezing
• Flushing
• Diarrhea, nausea, abdominal cramping

Antigens, the proteins mentioned earlier, cause your immune system to produce antibodies. These antibodies bind with the antigens and build up on the layers of cells that line the heart, blood vessels, lymph vessels, and other body cavities. This leads causes inflammation and other symptoms of serum sickness.

Penicillins are the most common cause of serum sickness. Other causes include:

• Other antibiotics; fluoxetine used for depression; barbiturates; a class of diuretics called thiazides; products that contain aspirin; other medications
• Snake venom antiserum
• Bee or wasp sting (rare)

You are more likely to suffer from serum sickness if

• You are injection with one of the drugs or antitoxin known to cause serum sickness
• You require a large amount of snake venom antiserum
• You have previously been exposed to a drug or antitoxin known to cause serum sickness

Your doctor will look for typical symptoms and ask if you have been recently exposed to any antiserum. Your doctor may order blood and urine tests.

Prevention

• If you know that you are sensitive to a particular drug or antiserum, you should tell your health care provider before you get any kind of injection.
• A health care provider can perform skin tests to check for serum sensitivity before giving antiserum.
• If you are sensitive to an antiserum, your health care provider may use a method that desensitizes you to the antiserum, at least temporarily.

Drug Therapies

Treatment for serum sickness is aimed at reducing symptoms. Your doctor may prescribe antihistamines or analgesics (nonsteroidal anti-inflammatory drugs), along with topical medications to relieve itching or rash. In serious cases, your doctor may prescribe corticosteroids, such as prednisone. Normally, there is no need for hospitalization.

Complementary and Alternative Therapies

If you suspect you have serum sickness, you should see a doctor immediately and receive conventional medical treatment. Some CAM therapies may support conventional treatment by helping to reduce inflammation and stabilize your immune system, but no scientific studies have been done on the effectiveness of CAM therapies for serum sickness. Although certain CAM therapies may help relieve symptoms, others could actually make them worse, so it's important to take any herb, supplement, or medication only under your doctor's supervision.

Nutrition and Supplements

The following nutrients may help support your immune system and reduce allergic reactions in general, though there is no scientific evidence that they will be effective for serum sickness and, as noted, some may make serum sickness worse. Talk to your doctor before taking any of these supplements.

• Vitamin C (1,000 mg two to six times per day for a short period) -- Lower dose if diarrhea develops.
• Choline -- Considered a B vitamin, found in meat and some vegetables.
• Inositol -- Considered a B vitamin, found in fruits, vegetables, whole grains, and organ meats.
• Quercetin (400 - 500 mg per day) -- a flavonoid and antioxidant found in many plants

Bromelain (250 mg two or three times per day) is an enzyme synthesized from pineapple that has anti-inflammatory properties. It is often combined with turmeric (Curcuma longa), which helps bromelain work better and has anti-inflammatory properties of its own. Do not take bromelain and turmeric if you take blood-thinning medication.

Although omega-3 fatty acids, found in fish oil, may have anti-inflammatory properties, one study suggested they might raise levels of antigen-antibody complexes in the body. Since these complexes can make serum sickness worse, it is best to avoid fish oil supplements when you already have the condition. Talk to your doctor about using fish oil as part of your preventive medicine regimen.

Herbs

Some herbs have antihistamine or anti-inflammatory properties that may be useful in treating symptoms of serum sickness.

Anti-inflammatories

• Siberian ginseng or Eleuthero root (Eleutherococcus senticosis, 500 mg to 3 g per day) -- may help support the immune system and act as an antioxidant. Note that Siberian ginseng is not the same as American or Panax ginseng. Do not take Siberian ginseng if you take blood-thinning medication or have diabetes or heart disease.
• Milk thistle (Silybummarianum, 200 - 400 mg silymarin, the active ingredient, per day) -- may decrease inflammation
• Cat's claw (Uncaria tomentosa, 250 mg per day) has anti-inflammatory and antioxidant effects. Do not take cat's claw if you have high blood pressure or take blood-thinning medication.
• Burdock (Arctium lappa, 2 - 6 g per day) is an anti-inflammatory and antioxidant. Do not take burdock if you have diabetes, take blood-thinning medication, or take a diuretic (water pills).

Antihistamines

• Ginkgo (Ginkgo biloba), 120 mg per day in two or three divided doses. Do not take ginkgo if you take blood-thinning medication
• Chinese skullcap (Scutellaria baicalensis), 1 - 2 g per day
• Peppermint oil (Menthae piperitae aetheroleum) --Peppermint oil can be dangerous in large doses, so take it only under the supervision of your health care provider, who can determine the proper dose for you.

You should avoid herbs that are more prone to causing allergic hypersensitivity reactions, such as cayenne pepper (Capsicumspp., used as an anti-inflammatory in treating arthritis).

Homeopathy

While few studies have examined the effectiveness of specific homeopathic remedies, professional homeopaths may recommend one or more of the following treatments for allergic reactions based on their knowledge and clinical experience. Before prescribing a remedy, homeopaths take into account a person's constitutional type -- your physical, emotional, and intellectual makeup. An experienced homeopath assesses all of these factors when determining the most appropriate remedy for a particular individual.

• Apis --for hives with intense burning as well as for swelling. People for whom this treatment is appropriate describe a stinging relieved by cool compresses.
• Rhus toxicodendron --for hives that are very itchy and relieved by warm compresses. A person for whom this is appropriate tends to be restless and must change positions frequently.
• Urtica urens -- for hives and other red, raised rashes that are painful, burning, and stinging but relieved by rubbing.

Acupuncture

Traditional Chinese Medicine and acupuncture can help lessen the body's tendency toward allergic hypersensitivity reactions.

Massage

Massage should not be used in cases of serum sickness as it may promote inflammation as well as lower blood pressure.

Serum sickness usually improves in 7 - 10 days, with full recovery in 2 - 3 weeks. However, it may lead to nervous system disorders as well as a life-threatening allergic reaction called anaphylaxis, so it is important to get medical treatment.

Healthcare providers should monitor seriously ill people for rare instances of myocarditis (inflammation of the heart muscle) and peripheral neuritis (nerve inflammation).

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