Allergy skin testing is a clinical procedure that is used to evaluate an
immunologic response to allergenic material. The need for testing and
interpretation of test findings must be correlated with signs and symptoms of
possible allergies as determined by a complete history and physical
examination of the patient. The number and type of antigens used for testing
must be chosen judiciously given the patient's presentation and the tester's
clinical judgment.  
  
Allergy testing is covered when a patient presents with clinically significant
allergic history or symptoms that are not controllable by empiric conservative
therapy. For Medicare to cover allergy testing, all of the following criteria
**must** be met:

  * Testing must correlate specifically to the patient's history and physical findings.
  * The test technique and/or allergens tested must have proven efficacy demonstrated through scientifically valid medical studies published in peer-reviewed literature.
  * Allergy testing must be performed on patients whose environment provides the reasonable probability of exposure to the specific antigen tested.

Percutaneous testing is the usual preferred method for allergy testing.
Medicare covers percutaneous (scratch, prick or puncture) testing when
documented IgE-mediated reactions occur to **any** of the following:

  * Inhalants
  * Foods
  * Hymenoptera (stinging insects)
  * Specific drugs (penicillins and macromolecular agents)

In selected patients, intradermal testing for the same antigen may be
necessary to test persons whose percutaneous test was negative. For
intradermal testing, the clinician should narrow the area of investigation so
that the minimal number of skin tests necessary for diagnosis is performed.
Medicare covers **intradermal (intracutaneous)** testing when documented IgE-
mediated reactions occur to **any** of the following:

  * Inhalants
  * Hymenoptera (stinging insects)
  * Specific drugs (penicillins and macromolecular agents)

Retesting with the same antigen(s) should rarely be necessary within a 3-year
period. Exceptions include young children with negative skin tests, or older
children and adults with negative skin tests in the face of persistent
symptoms. Routine repetition of skin tests is not indicated (i.e., annually).
If under specific circumstances, extensive repeat testing is required within a
3-year period, those circumstances must be clearly documented in the medical
record including an explanation as to why the original testing is
unacceptable.

Percutaneous testing for food allergens is covered for patients with a
clinical presentation suggestive of significant IgE mediated food allergy.
Such patients will have presented with signs and symptoms of such conditions
as angioedema, urticaria or anaphylaxis after ingestion of specific foods.
Testing for food allergies in patients who present with significant
respiratory symptoms alone may be required in certain instances.

The following allergy testing is **non-covered by Medicare:**

  *  Provocative and neutralization testing and neutralization therapy of food allergies (sublingual, intracutaneous and subcutaneous) are excluded from Medicare coverage because available evidence does not show these tests and therapies are effective
  * Qualitative multiallergen screens have insufficient literature demonstrating clear-cut clinical utility and are, therefore, non-covered
  * Late reactions occurring with allergenic extracts are of unclear clinical significance and are, therefore, non-covered
  * Intradermal testing for food allergens
  * Food allergen testing for patients who present with respiratory symptoms other than wheezing and asthma
  * Food allergen testing for patients who present with gastrointestinal symptoms suggestive of food intolerance
  * Skin endpoint testing
  * Allergy testing for antigens for which no clinical efficacy is documented in peer-reviewed literature. Such antigens include but are not limited to the following: 

  *     * Grain mill dust (pollen grains of cereals/related crops are large; they do not become airborne)
    * Tobacco smoke (no component has ever been shown to be a respiratory allergen)
    * Orris root (almost never used in cosmetics these days; test adds nothing to evaluation)
    * Dandelion (non-allergenic; no pollen produced)
    * Marigold (non-allergenic; no airborne pollen produced)
    * Honeysuckle (non-allergenic; non-significant airborne pollen produced)

Allergy testing for certain antigens is covered only when performed on
patients whose environment provides the reasonable probability of their
exposure to antigens tested. Such antigens include, but are not limited to the
following:

  * Tobacco leaf for tobacco workers
  * Pyrethrum for florists (non-allergenic; found in some insecticides; cross-reacts strongly with ragweed)
  * Golden rod for florists (pollen not carried by wind)
  * Soybean dust for workers in food processing plants
  * Wool for patients exposed to sheep or unprocessed wool (processed wool is non-allergenic)