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A 56-year-old male asked:

Female 38 rast blood test result level 3 high- ige:17 iu/ml (3.5 -17.5iu/ml)a delayed rash 2 days after finished course flucloxicillin.allergy consultant"no need for drug challenge"but concerned may be a false positive, had penicillin in past,advice?

1 doctor answer1 doctor weighed in
Dr. Amrita Dosanjh
Pediatric Allergy and Asthma 37 years experience
The CAP or RAST test is elevated and given the rash after exposure to the antibiotic, consider avoidance if possible. The rash also may have been a viral rash. Watch for signs of shortness of breath, wheezing and swelling. Repeat testing in a few months is recommended.
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Last updated Mar 4, 2022


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