Many times I am asked by a patient who has known allergies which form of allergy treatment is best, conventional immunotherapy shots or newer allergy drops given at home under the tongue. My office does both forms. I want to give more details on the drop method.
Sublingual immunotherapy (SLIT), also called allergy drops, works similar to allergy shots by gradually helping your body build tolerance to the substance(s) causing your allergies. The difference is that the antigen is placed under your tongue in a liquid drop form instead of an injection. The area under the tongue has the highest concentration of antigen/allergen presenting cells found anywhere in the body. This cell, called the dendritic cell, is the messenger that delivers antigens to the cells that enable allergic tolerance. By consistently delivering allergy drops to this cell daily, the body learns to tolerate things that cause allergic reaction.
We recommend patients take an allergy drop dose three times each day for 3-5 years. Treatment length may vary based on allergy severity and type, and how well people follow treatment guidelines. Many people feel better within a few months, but continuing treatment through all phases is necessary to help you stay symptom-free after your allergy drop treatment is complete.
Allergy drops work in three phases:
Phase 1: Initial Oral Tolerance (0-3 months)
During this phase, your body adjusts to treatment and symptoms can improve. Those with minor oral itching will see it decrease as tolerance begins.
Phase 2: Symptom Relief (3 months-2 years)
As symptoms decrease, your body is taking steps toward changing your allergen tolerance. You might feel tempted to stop your treatment because you feel better, but don’t. By continuing treatment, your body can learn long-term tolerance.
Phase 3: Long-term Tolerance (2-5 years*)
As symptoms continue to improve, your body increases its allergy tolerance. This long-term learning is needed for you to stay symptom-free long after treatment is done.
*Depending upon the severity of your allergies, your provider will monitor, adjust, and retest to determine the final length of treatment which varies between patients.
Allergy drops have been used around the world for more than 100 years with many studies showing that they are safe and effective. Allergy drops were used by physicians before they used allergy shots. There has never been a life-threatening reaction reported from the slow build-up protocol that I use in my office.
Internationally, sublingual immunotherapy is widely used, with full regulatory and government backing.
The World Health Organization (WHO) indicated its use in its 1998 position paper. In 2007, for the second time (originally in 2001), an international workgroup that included U.S. allergists published the ARIA (Allergic Rhinitis and its Impact on Asthma) guidelines indicating sublingual immunotherapy as a viable treatment approach. The ARIA paper also indicates that not only is there more modern research on sublingual immunotherapy compared to subcutaneous immunotherapy, but it is also of higher quality in terms of WHO guidelines for research studies.
A Cochrane Review, the most trusted, independent, evidence-based, meta-analysis organization in the world, released their analysis in 2003 and determined sublingual immunotherapy both safe and effective, and reinforced this in its 2010 update.
While these worldwide organizations approve the use of SLIT, unfortunately the US FDA has not officially approved them. This means Medicare and health insurance companies do not cover the cost. However the cost is reasonable. And most patients find their need for other symptom-relieving prescriptions decrease once they start allergy drops, or may no longer be needed. And there are generally fewer follow up visit costs, and less time lost from work/school. All of this means less true out of pocket costs. Additionally, allergy drops typically qualify for Health Savings Account or Flex Spending reimbursement.