Salicylate sensitivity, also known as salicylate intolerance, is any adverse effect that occurs when a usual amount of salicylate is ingested. People with salicylate intolerance are unable to consume a normal amount of salicylate without adverse effects.
Salicylate sensitivity differs from salicylism, which occurs when an individual takes an overdose of salicylates. Salicylate overdose can occur in people without salicylate sensitivity, and can be deadly if untreated. For more information, see aspirin poisoning.
Salicylates are derivatives of salicylic acid that occur naturally in plants and serve as a natural immune hormone and preservative, protecting the plants against diseases, insects, fungi, and harmful bacteria. Salicylates can also be found in many medications, perfumes and preservatives. Both natural and synthetic salicylates can cause health problems in anyone when consumed in large doses. But for those who are salicylate intolerant, even small doses of salicylate can cause adverse reactions.
Terminology
Depending on whether the salicylate is a component of food or medicine, salicylate intolerance is a form of food intolerance or of drug intolerance.
Salicylate sensitivity is a pharmacological reaction, not a true IgE-mediated allergy. However, it is possible for aspirin to trigger non-allergic hypersensitivity reactions. About 5-10% of asthmatics have aspirin hypersensitivity, but dietary salicylates have been shown not to contribute to this. The reactions in AERD (Samter's Triad) are due to inhibition of the COX-1 enzyme by aspirin, as well as other NSAIDs that are not salicylates. Dietary salicylates have not been shown to significantly effect COX-1.
Samter's triad refers to aspirin sensitivity in conjunction with nasal polyps and asthma.
History
An important salicylate drug is aspirin, which has a long history. Aspirin intolerance was widely known by 1975, when the understanding began to emerge that it is a pharmacological reaction, not an allergy.
Symptoms
The most common symptoms of salicylate sensitivity are:
- Stomach pain/upset stomach
- Tinnitus ringing of the ears
- Itchy skin, hives or rashes
- Asthma and other breathing difficulties
- Angioedema
- Headaches
- Swelling of hands, feet, eyelids, face and/or lips
- Bed wetting or urgency to pass water
- Persistent cough
- Changes in skin color/skin discoloration
- Fatigue
- Sore, itchy, puffy or burning eyes
- Sinusitis/Nasal polyps
- Diarrhea
- Nausea
- Hyperactivity
- Memory loss and poor concentration
- Depression
- Pseudoanaphylaxis
Diagnosis
There are no laboratory or skin testing methods for testing salicylate sensitivity. Provocative challenge is one method of obtaining reliable diagnosis. Provocative challenge is intended to induce a controlled reaction as a means of confirming diagnosis. During provocative challenge, the person is given incrementally higher doses of salicylates, usually aspirin, under medical supervision, until either symptoms appear or the likelihood of symptoms appearing is ruled out.
Treatment
Completely eliminating salicylate from one’s diet and environment is virtually impossible and is not a recommended course of action by many immunologists. The range of foods that have no salicylate content is very limited, and consequently salicylate-free diets are very restricted.
Desensitization involves daily administration of progressive doses of salicylate. This process is usually performed as an inpatient, with a crash-cart at the bedside over a six-day period, beginning with 25Â mg of I.V. lysine-aspirin and progressing to 500Â mg if tolerated.
Montelukast is one form of treatment used in aspirin-intolerant asthma.
See also
- NSAID hypersensitivity reactions
- Aspirin-induced asthma
References
External links
- Salicylate Sensitivity Forums and Food/Product Guides
- Aspirin sensitivity at the Journal of the American Medical Association patients' page