Labs providing allergy reports of smoke, medicines, cosmetics by a mere blood test should caution you for its genuineness.
Do you visit a laboratory or consult a doctor for your fever?
You buy a over the counter medicine by getting your blood pressure checked by pathologist ? If your answer is NO, then you should visit an allergist for any allergy related queries.
allergens act in so many different ways that it needs to be evaluated in individualized manner. Your allergist decides upon the need of investigations after a thorough history.
Lab tests relying on blood investigations can cost you dear creating unnecessary confusion and adding more problems rather solving it.
So, next time you see or hear an ad claiming to reveal your allergy , visit your doctor first !