A new clinical review provides useful information about the potential presence of food allergens in prescription medications. Although some medications and vaccines do contain substances derived from foods, researchers found that most medications do not contain enough of a food protein to cause an allergic reaction.
In the article published in the June 2014 issue of the Journal of Allergy and Clinical Immunology, Dr. John M. Kelso (Scripps Clinic, San Diego, CA) explains that all medications contain excipients, substances that are added to the active ingredient of a drug during the manufacturing process. Examples include flavoring agents, preservatives and binding materials. The article offers a thorough review of medications that contain food-derived excipients and discusses whether each is safe for patients with food allergies. For example, the MMR (measles-mumps-rubella) vaccine contains negligible or no egg protein and can be given to anyone with egg allergy. The typically available influenza vaccine contains trace amounts of egg protein, but authoritative professional associations have issued statements recommending vaccination for those with egg allergy and declaring that it may be administered safely with some precautions. On the other hand, some vaccines, including MMR, may trigger a reaction in people who are allergic to gelatin. Fortunately, this allergy is not common. People with fish allergy may safely consume fish oil, since it does not contain fish protein.
Dr. Kelso further notes that if a person does have a reaction to a medication, the drug may be from a specific lot that was accidentally contaminated with food protein. “In most circumstances these medications should not be routinely withheld from patients who have particular food allergies because most will tolerate the medications uneventfully,” he writes. “However, if a particular patient has had an allergic reaction to the medication… allergy to the food component should be investigated.”