What are the considerations for patients taking beta (beta-adrenergic blocking agents) blockers who require allergy testing?

From the Guidelines

Patients taking beta blockers who require allergy testing should ideally discontinue these medications before testing, if possible, due to the potential for beta blockers to interfere with the accuracy of test results and the treatment of potential anaphylactic reactions, as noted in studies such as 1 and 1. When considering the discontinuation of beta blockers, it's crucial to weigh the risks and benefits, taking into account the patient's specific condition and the potential for rebound hypertension, tachycardia, or exacerbation of underlying cardiovascular conditions.

• The decision to discontinue beta blockers should be made in consultation with the prescribing physician.
• If beta blockers cannot be safely discontinued, the allergist may proceed with modified testing protocols, using smaller initial doses and proceeding more cautiously, as suggested by guidelines such as those found in 1 and 1.
• The concern with beta blockers is twofold: they can mask early signs of anaphylaxis, such as tachycardia, and they can reduce the effectiveness of epinephrine, the primary treatment for severe allergic reactions.
• Additionally, patients on beta blockers may experience more severe anaphylaxis due to unopposed alpha-adrenergic effects.
• For patients who cannot stop their beta blockers, emergency medications like glucagon may be kept available during testing, as it can help restore cardiac responsiveness to epinephrine if needed, highlighting the importance of careful management and preparedness in these cases.

From the FDA Drug Label

Beta-adrenergic blocking drugs: antagonize the cardiostimulating and bronchodilating effects of epinephrine ( 7)

Patients taking beta blockers who require allergy testing should be aware that beta-adrenergic blocking drugs may antagonize the cardiostimulating and bronchodilating effects of epinephrine. This interaction may be relevant in the context of anaphylaxis treatment, where epinephrine is often administered.

• Key consideration: The presence of beta blockers may affect the response to epinephrine in emergency situations, such as anaphylaxis.
• Clinical decision: Caution should be exercised when administering epinephrine to patients taking beta blockers, as the effectiveness of epinephrine may be reduced 2.

From the Research

Considerations for Patients Taking Beta Blockers Who Require Allergy Testing

• Patients taking beta blockers who require allergy testing should be aware of the potential risks and considerations associated with their medication [(3,4,5)].
• Beta blockers may increase the severity and incidence of acute anaphylaxis, and may interfere with the treatment of anaphylaxis 3.
• Allergy skin testing or immunotherapy is generally inadvisable in patients who take beta blockers orally or in the form of ophthalmic eyedrops 3.
• However, some studies suggest that skin prick testing may be safe in patients taking beta blockers, with no adverse events reported in a retrospective analysis of 191 patients 5.

Beta Blockers and Anaphylaxis

• Beta blockers may aggravate anaphylactic reactions and interfere with treatment, which is a concern for patients with a history of anaphylaxis or those undergoing allergen immunotherapy 4.
• The combination of beta blockers with venom immunotherapy may be indicated in heavily exposed patients with severe cardiovascular disease, but this should be done with caution and close monitoring 4.

Alternative Beta Blockers

• In cases where a patient experiences an allergic reaction to a beta blocker, alternative beta blockers may be considered 6.
• For example, bisoprolol, a second-generation beta blocker, has been shown to be a safe alternative in a patient who experienced an urticaria reaction to propranolol 6.

Medications that Interfere with Allergy Skin Testing

• Certain medications, including tricyclic antidepressants, H1-antagonists, and benzodiazepines, may interfere with allergy skin test interpretation 7.
• However, selective serotonin reuptake inhibitors, selective norepinephrine reuptake inhibitors, and proton pump inhibitors are unlikely to interfere with skin testing 7.