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Sublingual immunotherapy (SLIT) is an alternative way to treat allergies without injections. An allergist gives a patient small doses of an allergen under the tongue to boost tolerance to the substance and reduce symptoms.

 Currently, the only forms of SLIT approved by the FDA are tablets for ragweed and grass pollen.  The safety and efficacy of allergy drops is still being established by the FDA, and they are only used off-label in the United States.

How Is Treatment Administered?

An allergist must first use allergy testing to confirm the patient’s sensitivities. Once this is determined, an allergen extract is prepared in drop form or the tablet is prescribed.  The patient is directed to keep it under the tongue for one to two minutes and then swallow it. The process is repeated from three days a week to as often as daily with recommendations that therapy is continued for three to five years to develop a lasting immunity.

Is Sublingual Immunotherapy Effective and Safe?

Most clinical trials and surveys published over at least 20 years show that SLIT is relatively safe and effective for the treatment of rhinitis and asthma caused by allergies to dust mites, grass, ragweed, cat dander, and tree pollens. Evidence is emerging that SLIT may be effective for treating the red, itchy eyes caused by pollen during hay fever season. In addition, it might prove an effective therapy for children with mild atopic dermatitis (eczema) and is currently being studied for its potential in treating food allergies.

Side effects among both children and adults are usually local and mild, most often occur early in treatment, and include itching in the mouth or stomach problems. These can usually be managed by dose adjustments. Very rarely, severe allergic reactions (anaphylaxis) have been reported using SLIT. Therefore this treatment is best prescribed by an allergist.

What Are the Risks of Sublingual Immunotherapy?

For the most part, SLIT risks relate to the nature of the treatment: it is administered at home and without direct medical supervision. Patients should therefore receive clear guidance from allergists on managing adverse reactions and treatment interruptions and should know when to consult the prescribing allergist.

Learn more about this therapy and get relief by consulting with an allergist.

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