From the Guidelines
No, it is not safe to administer allergy immunotherapy that is 1 month past its expiration date. The potency and stability of allergy immunotherapy extracts are influenced by several factors, including storage temperature, presence of stabilizers and bactericidal agents, concentration, presence of proteolytic enzymes, and volume of the storage vial 1. According to the study, the expiration date for more dilute concentrations of allergy immunotherapy extracts should reflect their shorter shelf life, and the potency of concentrated allergen immunotherapy extracts is relatively constant when kept at 4°C, but less concentrated extracts are more sensitive to the effects of temperature and might not maintain their potency until the listed expiration date 1.
The study also notes that the expiration date of any dilution should not exceed the expiration date of the earliest expiring constituent that is added to the mixture 1. This suggests that even if the extract itself is still potent, the presence of other components with shorter expiration dates could compromise the safety and efficacy of the treatment.
Key points to consider:
- The potency and stability of allergy immunotherapy extracts decrease over time, especially for more dilute concentrations 1.
- The expiration date on the label is established based on stability testing and is a critical safety measure, especially for injectable medications like allergy shots where precision dosing is essential for both effectiveness and safety.
- Using expired allergy immunotherapy could result in treatment failure or increased risk of adverse reactions, including severe allergic reactions or anaphylaxis.
- If you have expired allergy immunotherapy, contact your allergist or healthcare provider immediately to obtain a new, unexpired prescription. Never attempt to adjust dosing of expired medication thinking it might compensate for potential degradation.
From the Research
Safety of Expired Allergy Immunotherapy
- The safety of administering allergy immunotherapy that is 1 month past its expiration date is not directly addressed in the provided studies 2, 3, 4, 5.
- However, a study on the use of expired drugs suggests that some medications, if properly stored, remain safe to use after the expiry date, which could be extended by many years 6.
- It is essential to note that the pharmaceutical manufacturers have an interest in producing products with short shelf life, and disposing of expired ones can generate sales and profit for the development of new products 6.
- There is no specific guidance on the safety of expired allergy immunotherapy in the provided studies, and it is crucial to consider the potential risks and benefits before administering expired medication.
- The decision to use expired allergy immunotherapy should be made on a case-by-case basis, taking into account the specific medication, storage conditions, and patient factors, and in consultation with a qualified healthcare professional.