Sublingual Immunotherapy Side Effects and Warnings

Safety Issues

SLIT appears to be safer than conventional allergy shots. The most frequent report of adverse effects include oral itching or swelling, as well as gastrointestinal upset; in the great majority of cases, these are mild and short-lived.^{1 2} In one study, 12% of patients with allergic rhinitis and/or asthma experienced worsening of symptoms at some point in their treatment. ³ Severe allergic reactions appear to occur rarely. However, it has not been tested in high-risk asthma patients. ⁴ Another problem is that no allergy extracts for use in sublingual immunotherapy have been officially approved for use in the US, and therefore products available remain incompletely regulated.