According to the Food and Drug Administration, or FDA, all prescription drug products are required to include certain categories of information in their product inserts, also known as professional labeling information. The purpose of this is to provide patients and doctors with information that is necessary for safe and effective use. One of the categories of information that drug makers must provide is "warnings." For the 2009-10 flu season, the FDA required manufacturers to issue three kinds of flu shot warnings.
Guillain-Barre Syndrome
According to the National Institute for Neurological Disorders and Stroke, Guillain-Barre Syndrome, or GBS, is an autoimmune disease in which a person's own immune system makes antibodies against parts of the peripheral nervous system. Early symptoms include tingling and muscle weakness in the legs. As the disease progresses, symptoms spread to the arms and trunk and may increase in intensity to the point that the person is paralyzed. According to the Centers for Disease Control and Prevention, or CDC, approximately 5 to 6 six percent of people with GBS will die. Recovery is often prolonged--several weeks to years--and some deficits may be permanent. The CDC estimates the risk of developing GBS after the flu vaccine to be approximately 1 in 1 million. The decision to re-vaccinate a person who previously developed GBS within six weeks of receiving the flu shot should be based on careful consideration of the potential risks and benefits.
Altered Immunocompetence
Immunocompromised people, including those receiving immunosuppressive therapy, may have a diminished response to the flu shot. According to the CDC, the vaccine works when a person's immune system makes antibodies against the killed viruses in the vaccine. People with abnormal immune systems and people taking certain kinds of drugs that suppress the immune system--organ transplant recipients and people with autoimmune diseases, for example---may not have an effective response to the vaccine. However, these people should still get the flu shot because they are also at high risk for serious flu-related complications. FluMist, the live attenuated intranasal vaccine and the only flu vaccine that is not a shot, is contraindicated in people with altered immunocompetence.
Dry Natural Latex Rubber
Fluarix, from GlaxoSmithKline Biologicals, was the only brand of flu shot required to issue a third warning on the potential for allergic reactions due to dry natural latex rubber, a component of the needleless prefilled syringes used to dispense the product. According to the American College of Allergy, Asthma and Immunology, latex allergy is one of the most common causes of anaphylaxis, a severe, life-threatening allergic reaction. Symptoms of anaphylaxis include breathing problems, hives, throat tightness, nausea, vomiting, abdominal pain, diarrhea, dizziness, low blood pressure, rapid heart beat, a feeling of doom and cardiac arrest. People with latex allergies should choose one of the four other latex-free brands of flu shot approved for 2009-10.
