Low Dose Allergen (LDA) – Overview

Low Dose Allergen (LDA) was originally called Enzyme Potentiated Desensitization (EPD).

This allergy treatment was discovered in the early 1960s by Dr. S. Popper – and is the case with many medical discoveries, luck played a major role.

Dr. Popper used Beta Glucaronidase (the enzyme used for LDA) and inserted this in a patient's nose to remove a polyp. The polyp remained unchanged, but pollen allergies were completely eliminated.

Then, Dr. Leonard McKewin (England) teamed-up with Dr. Butch Shrader. They worked together for over 20 years in making LDA state of the art allergy treatment.

How Does LDA Work?

Beta Glucaronidase (the enzyme) is mixed with low doses of allergens and shifts the immune system from an allergic state (Th2) to a less allergic state (Th1).

When LDA is injected, T suppressor cells are produced that block T-helper cells to control various allergic medical conditions.


When EPD (now LDA) was started in the United States early 1990s, Drs. Shrader and McKewin actually published a study of 80 patients showing a 75-80% success rate. There had been no reported serious side effects from EPD or LDA. This success rate is much higher than other allergy therapy interventions.

Unfortunately when Drs. Shrader and McKewin applied for FDA approval, they were told that $800-million was needed for studies. This basically means that only wealthy pharmaceutical companies can afford the FDA medical treatment studies.

FDA foolishly banned EPD in 2001 even though this treatment was reported to be safe and effective with an 80% success rate.

Now prepared at a compounding pharmacy, LDA does not require FDA approval.