Contrary to popular belief, cat hair itself is not allergenic
Standardized Cat Hair Extract is a clear, light yellow to amber solution of the allergens of cat hair, extracted in buffered saline containing sodium chloride, sodium bicarbonate and 50% glycerol by volume. Phenol at 0.4% w/v is added as a preservative.
Source material for the extract is obtained from the hair of the domestic cat. The importance of surface allergens in cat allergy has been shown in several investigations .
The potency of Standardized Cat Hair Extract is based on the amount of Fel d allergen in the extract. Extract containing 5-9.9 units per mL is assigned a potency of 5,000 Bioequivalent Allergy Units (BAU/mL). Extract containing 10-19.9 Fel d units is assigned a potency of 10,000 BAU/mL. BAU/mL values are based on quantitative skin testing. The primary allergen of Standardized Cat Hair Extract is Fel d. Standardized Cat Pelt Extract contains Fel d, as well as non-Fel d allergens. The latter are believed to be components of cat serum, such as albumin. Pelt extracts have a higher protein content than hair extracts, and the isoelectric focusing (IEF) pattern of the pelt extract reveals protein bands that are not present in cat hair extracts. The IEF pattern of cat hair extracts shows primarily Fel d allergen without serum components. The importance of Fel d as a means of standardizing the potency of cat extract is based on the following observations:
Standardized Cat Hair Extract may cause local or severe life-threatening reactions when administered to highly sensitive individuals. Physicians who use this product should be familiar with the clinical use of allergenic extract and have the necessary emergency equipment and medications available to treat systematic allergic reactions. See Precautions, Adverse Reactions and Overdosage.
Standardized Cat Hair Extract should not be used interchangeably with Standardized Cat Pelt Extracts or previously standardized cat extracts labeled in Allergy Units per mL. Cat hair extracts labeled in BAU/mL made by other manufacturers should be tested for bioequivalency by serial titration skin testing before these products are used in patients who have previously received Allermed Standardized Cat Hair Extract.
The dosage of Standardized Cat Hair Extract must be reduced when starting a patient on a new lot of Standardized Cat Hair Extract containing the same amount of Fel d units per mL. This is necessary due to a possible loss of potency during storage in the physician's office. The dose of the new lot of extract should not exceed 1/4 the last dose given from the old lot of extract.
Any evidence of a strong local reaction or systemic reaction following the administration of Standardized Cat Hair Extract requires a reduction in dosage during the initial stages of immunotherapy, as well as during maintenance therapy.
STANDARDIZED CAT HAIR EXTRACT WITH POTENCY LABELING IN BIOEQUIVALENT ALLERGY UNITS per mL (BAU/mL) IS NOT INTERCHANGEABLE WITH OTHER CAT EXTRACTS. STANDARDIZED CAT HAIR EXTRACT IS NOT INTERCHANGEABLE WITH STANDARDIZED CAT PELT EXTRACTS LABELED IN BIOEQUIVALENT ALLERGY UNITS OR WITH OTHER CAT EXTRACTS LABELED IN ALLERGY UNITS (AU).
Standardized Cat Hair Extract is a sterile solution for intracutaneous or subcutaneous administration. The extract is standardized by comparing potency in cat allergen 1 (Fel d I) units measured by radial immunodiffusion against a referencestandard from the Center for Biologics Evaluation and Research of the U.S. Food and Drug Administration (FDA).(1-3) An extract with 10 to 19.9 Fel d I units per mL is designated as 10,000 Bioequivalent Allergy Units/mL (BAU/mL) by the FDA based on quantitative skin testing.(2) Greer Standardized Cat Hair Extract concentrate is 10,000 BAU/mL.
THE INITIAL DOSE OF STANDARDIZED CAT HAIR EXTRACT MUST BE BASED ON SKIN TESTING AS DESCRIBED IN THE DOSAGE AND ADMINISTRATION SECTION OF THIS INSERT. PATIENTS BEING SWITCHED FROM OTHER TYPES OF EXTRACTS TO STANDARDIZED CAT HAIR EXTRACT SHOULD BE INSTRUCTED TO RECOGNIZE ADVERSE REACTION SYMPTOMS AND CAUTIONED TO CONTACT THE PHYSICIAN’S OFFICE IF REACTION SYMPTOMS OCCUR. IN CERTAIN INDIVIDUALS THESE REACTIONS COULD BE FATAL. PATIENTS SHOULD BE OBSERVED FOR AT LEAST 20 MINUTES FOLLOWING IMMUNOTHERAPY. PATIENTS WITH LABILE OR STEROID-DEPENDENT ASTHMA ARE “HIGH RISK PATIENTS” WHO REQUIRE SPECIAL CAUTION IN DOSE ADMINISTRATION AND SHOULD REMAIN IN THE OFFICE FOR AT LEAST 30 MINUTES. AIRWAY OBSTRUCTION IN HIGH RISK PATIENTS CAN BE MONITORED BY PEAK FLOW MEASUREMENTS BEFORE AND AFTER ADMINISTRATION OF ALLERGENS. EMERGENCY MEASURES AS WELL AS PERSONNEL TRAINED IN THEIR USE SHOULD BE IMMEDIATELY AVAILABLE IN THE EVENT OF A LIFE THREATENING REACTION. PATIENTS BEING SWITCHED FROM ONE LOT OF EXTRACT TO ANOTHER FROM THE SAME MANUFACTURER SHOULD HAVE THEIR DOSE REDUCED BY 75%. Pet owners often complain about cat hair allergy. People are not actually allergic to cat hair, but to a protein in cat dander and saliva. A person that is allergic to cats develops histamines in excess, and this will lead to several unpleasant symptoms.