Depending on your doctor's judgment, he or she may recommend a graded drug challenge if the diagnosis of a drug allergy is uncertain. Starting with a small dose and increasing to the desired dosage, you receive two to five doses of the drug. Your doctor will conclude that you are not allergic to the drug if you reach the therapeutic dose without reacting.   Taking a drug that causes an allergic reaction can be treated with drug desensitization if you need to take it. As part of this treatment, you receive very small doses every 15 to 30 minutes over a period of several hours or days, followed by progressively larger doses. Continuing treatment is okay if you can reach the desired dosage without experiencing any side effects.   Drug allergy diagnosis and treatments are available at Allergy and Asthma Care of Rockland, P.C.   We serve patients from Suffern NY, Monroe NY, New City NY, Spring Valley NY, Monsey NY, Airmont NY and Mahwah NJ and surrounding areas.