Flushed and itchy after smoked mackerel, or hives after a mackerel pâté? Two very different things can cause that: an IgE allergy to mackerel protein, or histamine from fish that was not kept cold. Our test checks your blood for IgE to whole mackerel and to mackerel parvalbumin, as part of 300 allergens and allergen components, including the fish worm Anisakis.
Mackerel is a bony fish, like cod, herring and salmon. Its main allergen is parvalbumin, a small muscle protein called Sco s 1 in Atlantic mackerel. Parvalbumins from different fish look alike, so many people sensitised to one fish show IgE to several.
Dark-fleshed fish such as mackerel and tuna tend to contain less parvalbumin than white fish such as cod. That is a tendency, not a rule, and not a reason to try mackerel if you have reacted to other fish.
Mackerel is the classic fish for scombroid poisoning. If it is not chilled properly, bacteria turn a natural amino acid into histamine. Eating it can cause flushing, headache, a peppery taste and a rash in anyone, often within an hour. That is food poisoning, not an allergy, and it does not show up as IgE.
Mackerel can also carry larvae of Anisakis, a fish worm. Some people react to the worm's proteins rather than to the fish. Our panel measures two Anisakis proteins, so your report separates the two.
Reactions people describe after eating fish include itching in the mouth, hives, swollen lips, stomach cramps, vomiting and wheezing. They usually start within minutes to two hours. Some people react to steam from cooking fish.
Swelling of the lips, tongue or throat, trouble breathing or feeling faint after eating is an emergency. Call 112 (EU) or your local emergency number. Do not wait for a test.
From a finger-prick sample, the lab measures IgE to a whole mackerel extract and to mackerel parvalbumin, a single protein (molecular component). Cod, salmon, herring, tuna, carp, swordfish, thornback ray and Anisakis are on the same panel of 300 allergens and allergen components.
Your lab report gives each value a class from Negative to Very high. That shows sensitisation, not a diagnosis. Discuss the result with a doctor before you change your diet.
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One finger-prick sample checks IgE to 300 allergens and allergen components, from birch and peanut to cat and house dust mite. Post it to the lab, and about 5 days after it arrives you get a value for every one. Our plain-English guide shows you how to read them. €399 in total, €1.33 per allergen.
One common reason is histamine. Mackerel that was not kept cold can build up histamine and cause flushing and a rash in anyone, so the reaction depends on the batch. An IgE allergy to mackerel protein usually shows up every time. A test helps tell the two apart.
Some people are, but more often sensitisation covers several fish, because fish parvalbumins look alike. Testing mackerel next to cod, herring, salmon and tuna shows your pattern for a doctor to read.
Not reliably. Parvalbumin survives heat well. If you have reacted to mackerel in any form, talk to a doctor before eating it again.
