Don’t go nuts over food allergens in your medications! This article will go over the various types of food-based excipients and what the risk is for triggering an allergic reaction.


Why does my medication contain extra ingredients?

Your medications are composed of two types of components: the active drug and the inactive excipients. Excipients are used to stabilize, protect, and increase the tolerability of the drug. Some excipients can be food-derived substances.


What are the symptoms of a food allergy?

Most symptoms from food allergies are mild and limited to skin and digestive discomfort. This includes:

  • Rash, swelling, or redness of the skin
  • Vomiting, diarrhea, abdominal cramps
  • Dizziness, lightheadedness
  • Tingling, itching in the mouth

However, some allergies can lead to a severe, life-threatening allergic reaction called anaphylaxis. This can be characterized by:

  • Difficulty breathing, throat swelling, constricted airways
  • Hives
  • Severe blood pressure drop and shock (aka anaphylactic shock)
  • Angioedema (swelling in the face)
  • Frequent vomiting
  • Symptoms that required epinephrine or another emergency medical intervention

It is important to understand that anaphylaxis symptoms can start off as mild but quickly become life-threatening. Thus, it is important to know how to manage your symptoms as soon as they occur.


What types of food allergens can be present in medications? If I need to take a medication that contains an ingredient that I’m allergic to, what can I do?



Lactose is used in dry-powdered inhalers. Pharmaceutical-grade lactose is considered to contain very little to no milk protein. It is unlikely to cause a reaction if you have mild dairy allergy. However, if you have a severe dairy allergy, metered-dose inhalers are preferred because they use liquid medication and propellants that contain no lactose.

Common dry-powdered inhalers that contain lactose and may contain milk protein include:

  • Advair Diskus
  • Breo Ellipta
  • Flovent Diskus
  • Pulmicort Flexhaler
  • Spiriva HandiHaler
  • Trelegy Ellipta
  • Wixela Inhub

Other medications can also contain lactose (e.g. chewable cetirizine, montelukast 10 mg tablets). Like the dry-powdered inhalers, tablets and capsules that contain lactose will use pharmaceutical-grade lactose, which is unlikely to trigger an allergic reaction. Always check the package insert if you have a severe dairy allergy.


Egg lysozyme is an enzyme derived from egg whites. It can also be listed as lysozyme E1105. During manufacturing, trace amounts of residual egg protein called ovalbumin can be present.

There are several vaccines that contain lysozyme and thus small amounts of ovalbumin. This includes most flu vaccines. Regardless of severity, people with a history of egg allergy of can receive any licensed, recommended, and age-appropriate influenza vaccine. If you have an egg allergy, you will be observed for 30 minutes after receiving your flu vaccine.

If you had a severe allergic reaction to eggs in the past, you should be vaccinated under the supervision of a healthcare provider who can recognize and manage severe allergic reactions.


Fish and shellfish products are not as common but can still exist in medications. Fish oil is an obvious one. Glucosamine is a common dietary supplement used for osteoarthritis. Some glucosamine supplements are made from the shells of crabs, lobster, or shrimp. However, most shellfish allergies are usually based on the meat of shellfish rather than the shell, and many people with shellfish allergies can take glucosamine without adverse reactions.


Peanuts can be found in medications that are suspended in oil. Progesterone contains peanut oil. It can be used by post-menopausal women in combination with estrogen. If you need this medication, a compounding pharmacy can help formulate progesterone without peanut oil.

Sustanon also contains peanut oil. It is an injectable form of testosterone used for hormone replacement therapy. You should avoid this injectable if you have a severe peanut allergy.


What is the risk of these medications triggering an allergic reaction?

For the products discussed above, the risk of a severe allergic reaction is rare if you have mild food allergies. Each person with a food allergy has a different degree of sensitivity. For most people with food allergies, the trace amount of the allergen in most products would probably not be enough to cause a reaction.

If you are concerned about your risk for an allergic reaction, ask your prescriber for other options. They will help you weigh the risks versus benefits of taking the medication while considering the severity of reactions you have had in the past. Additionally, it is important to understand that anaphylaxis symptoms can start off as mild but quickly become life-threatening; thus it is important to educate yourself and your loved ones on how to respond to anaphylaxis (i.e. always have an Epi-pen available with you and immediately call emergency medical services).

Prepared by Judy Huynh PharmD Candidate 2022


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