Allergy - Diclofenac Pain Killer Test

Diclofenac is one of the commonly used drugs belonging to the family of nonsteroidal antiinflammatory drugs (NSAIDs). It is used to treat mild to moderate pain works by reducing substances in the body that cause pain and inflammation. Hypersensitivity reactions against diclofenac can manifest as Type I-like allergic reactions including systemic anaphylaxis. To protect the body from this perceived threat, or allergen, the immune system of an allergic person produces antibodies called immunoglobulin E. Specific immunoglobulin E (IgE) test is conducted to check if the person is allergic to a particular allergen, in this case, the drug diclofenac.

It is advisable that the patient inform the practitioner about the following prior to the testing: Your medical history Known and existing allergies List of other medications that have been consumed, including other NSAIDs and anti-histamines History of the allergic reaction specific to diclofenac (duration of the onset, severity of the allergic reaction and type of reaction) Based on this history, the practitioner may advice you about any diet restrictions, and usage of medications that need to be followed. It is recommended that you wear comfortable clothing that will allow easy access to your arm or back on the day of testing.

Specific IgE test for Diclofenac will help in assessing whether the adverse reaction is predictable (intolerance) or unpredictable (hypersensitive). Based on this the doctor may either lower the dosage or completely eliminate diclofenac and other related drugs from the prescription. The test will also indicate if further tests and analysis such as oral challenges, patch tests or in vitro in-vitro testing where a blood sample is collected are required and recommend them as required. The test will also be a part of the medical history, help the person be aware of the allergic reaction, and will be considered while prescribing medications in the future.

The recommended test for diclofenac allergy is in-vivo or the skin allergy test. The common method is the prick test done usually on the forearm or the back. This method involves a skin testing device such as a wheal and flare pricked through a droplet of allergenic extract. The wheal and flare is read in 15-20 minutes. It is measured in millimeters and compared with a positive control (histamine) and a negative control (usually glycerinated saline). A positive test is considered as a wheal equal to or larger to the histamine control (or greater than 3 mm).