🕷️ Crawler Inspector

URL Lookup

Direct Parameter Lookup

Raw Queries and Responses

1. Shard Calculation

Query:

Response:

Calculated Shard: 87 (from laksa143)

2. Crawled Status Check

Query:

curl -X POST \
  'http://laksa087.int.ahrefs:8124/' \
  -H 'Content-Type: text/plain' \
  -H 'X-ClickHouse-Database: crawler3' \
  -H 'Authorization: Basic YXBpOg==' \
  -d 'SELECT getAhrefsURLFromUnparsed(src_unparsed) AS found_url, ifNull(toUnixTimestamp(download_stamp), 0) AS crawl_time, ifNull(toUnixTimestamp(props_url_first_seen), 0) AS first_indexed_time, download_http_code AS http_code, src_unparsed AS src_unparsed, src_root_hash AS src_root_hash, history_drop_reason AS history_drop_reason, meta_title AS meta_title, meta_descriptions AS meta_descriptions, attrs_boilerpipe_text AS attrs_boilerpipe_text, attrs_markdown AS attrs_markdown, attrs_readable_markdown AS attrs_readable_markdown, meta_canonical AS meta_canonical FROM crawler3.page_info_local FINAL PREWHERE (src_root_hash, src_unparsed) IN ((getAhrefsRootHashFromUnparsed(getAhrefsUnparsedNoserviceFromURL(\'https://allergynorthwest.nhs.uk/resources/allergy-leaflets/shellfish-allergy/\')), getAhrefsUnparsedNoserviceFromURL(\'https://allergynorthwest.nhs.uk/resources/allergy-leaflets/shellfish-allergy/\'))) FORMAT JSONEachRow'

Response:

{"found_url":"https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/shellfish-allergy\/","crawl_time":1775225616,"first_indexed_time":1523420704,"http_code":200,"src_unparsed":"uk,nhs,allergynorthwest!\/resources\/allergy-leaflets\/shellfish-allergy\/ s443","src_root_hash":"12792222199549976887","history_drop_reason":null,"meta_title":"Shellfish Allergy - North West Allergy Network","meta_descriptions":[],"attrs_boilerpipe_text":"How common is shellfish allergy?\nShellfish includes shrimp, prawn, lobster, crab, clam, oyster and mussel. Shellfish allergy is less common in children than in adults. Children who are allergic to shellfish are usually not allergic to white fish, salmon and tuna.\nWhat are the symptoms of shellfish allergy?\nSymptoms can occur not only after eating shellfish, but also after contact or from breathing the shellfish vapour during cooking or at a fish market. Usually only a hives or “nettle” rash develops. Sometimes as well as a rash, swelling, especially around the face may occur. Some children have an itchy throat; others vomit or can have diarrhoea.\nSevere reactions are much less common, but can include difficulty in breathing (with wheeze or swelling in the throat), feeling faint or dizzy. Vapours from the shellfish may trigger an asthma attack in children that are allergic.\nHow serious is shellfish allergy?\nAllergic reactions are usually mild. Severe reactions affecting the child’s breathing can occur, particularly in those with bad asthma who need urgent medical attention.\nShellfish allergy can sometimes be confused with shellfish poisoning. This is also called ciguatera poisoning. It occurs in warmer weather because of algae in the water. The poison is not destroyed by cooking the shellfish. It generally occurs in seafood with two shells such as clams, oysters, mussels, and sometimes scallops.\nWill my child be allergic to other foods?\nShellfish and fish are different. People who are shellfish allergic may be able to eat fish. There are two different types of shellfish: molluscs and crustaceans. Molluscs include mussels, clams, oysters and squid. Crustaceans include prawns, shrimp, lobster, crab and crayfish. People who are allergic to one type of crustacean, such as prawn, are generally allergic to all other crustaceans but may be able to eat molluscs. Your allergist will be able to advise.\nHow do we diagnose shellfish allergy?\nThe diagnosis of shellfish allergy is suggested by a history of a reaction after contact with shellfish and a positive skin prick or blood IgE test. An oral challenge is required for a firm diagnosis, as recent evidence suggests that only 10-20% of children with a history of allergy to shellfish and positive allergy tests will react on hospital challenge.\nSkin prick tests can be done in clinic provided that the child has not had any antihistamines for a few days. Blood tests are not affected by antihistamines, but the results are only available in a week or so after the clinic appointment.\nHow can my child avoid shellfish?\nShellfish is easy to avoid. Some foods, such as Worcestershire sauce, steak sauce, fried rice, egg rolls, salad dressings, seafood muffaletta sandwiches can have shellfish as hidden ingredients. Cross contamination when buying fresh shellfish over the counter in shops and supermarkets can occur. Some dishes like paella, bouillabaisse, gumbo and frito misto contain lots of different kinds of fish at once, can be difficult to spot. It is useful to avoid such dishes. Some face creams and health supplement can have crushed shells.\nHow should you manage a reaction?\nAfter a reaction to shellfish, your child should be provided with advice about what to do if they have another reaction. The plan is usually written down – Allergy Management Plan.\nAfter a reaction to shellfish, your child should be provided with advice about what to do if they have another reaction. The plan is usually written down – Allergy Management Plan.\nMild reaction\n– hives, swelling or vomiting, but no breathing problems or faintness:\nIf possible, get the child to spit out the food. Give an antihistamine.\nSevere reaction\n–\ndifficulty breathing\n(wheezing, noisy breathing, blue colour);\nswelling in the throat\n(noisy breathing, drooling); feeling faint or dizzy,\nlooking very pale\n(lie the child down with their legs raised).\nGet help straight away and dial 999 stating “anaphylaxis” (ana-fil-ak-sis)\n.\nIf you have an adrenaline pen – use it.\nWho needs to know about this allergy?\nIt is important to inform the nursery\/school and any after school clubs. Any other carers will also need to know.\nIs Shellfish allergy life long?\nShellfish allergy is usually life-long. If there has been no reaction for a long time an oral challenge may be suggested.\nIs there a cure?\nThere is no cure for shellfish allergy at present.","attrs_markdown":"- Click here to add this page to your favorites\n- [Contact Us](https:\/\/allergynorthwest.nhs.uk\/about-us-2\/contact-us\/)\n- [Find our Allergy Centres](https:\/\/allergynorthwest.nhs.uk\/about-us-2\/where-we-are\/)\n\n[![North West Allergy Network](data:image\/svg+xml,%3Csvg%20xmlns='http:\/\/www.w3.org\/2000\/svg'%20viewBox='0%200%201300%20118'%3E%3C\/svg%3E)![North West Allergy Network](https:\/\/allergynorthwest.nhs.uk\/wp-content\/uploads\/2016\/12\/header1300-Frutiger.jpg)](https:\/\/allergynorthwest.nhs.uk\/ \"North West Allergy Network\")\n\n##\n\n### Toggle menu\n[Skip to content](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/shellfish-allergy\/#content \"Skip to content\")\n\n- [Home](https:\/\/allergynorthwest.nhs.uk\/)\n- [About Us](https:\/\/allergynorthwest.nhs.uk\/about-us-2\/)\n  - 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[Links](https:\/\/allergynorthwest.nhs.uk\/links\/)\n- [Resources](https:\/\/allergynorthwest.nhs.uk\/resources\/)\n  - [Allergy Leaflets](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/)\n    - [Food Allergies]()\n      - [Peanut Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/peanut-allergy\/)\n      - [Tree Nut Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/tree-nut-allergy\/)\n      - [Cow’s Milk Protein Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/cows-milk-protein-allergy\/)\n      - [Egg Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/egg-allergy\/)\n      - [Wheat Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/wheat-allergy\/)\n      - [Soya bean Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/soya-bean-allergy\/)\n      - [Allergy to Legumes & Pulses](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/legume\/)\n      - [Sesame Seed Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/sesame-seed-allergy\/)\n      - [Fish Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/fish-allergy\/)\n      - [Shellfish Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/shellfish-allergy\/)\n      - [Oral Allergy Syndrome (Food Pollen Syndrome)](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/oral-allergy-syndrome\/)\n      - [FPIES](https:\/\/allergynorthwest.nhs.uk\/home-patient\/managing-allergies\/patient-leaflets\/fpies\/)\n    - [Other Allergies]()\n      - [Chronic Urticaria and Angioedema](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/chronic-urticaria-and-angioedema\/)\n      - [Eczema (Atopic Dermatitis)](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/eczema-atopic-dermatitis\/)\n      - [Hay Fever (Allergic Rhinitis)](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/hay-fever-allergic-rhinitis\/)\n      - [House Dust Mite Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/housedustmiteavoidance\/)\n      - [Pet Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/pet-allergy\/)\n      - [Drug Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/drug-allergy\/)\n      - [Allergy to Insect Stings](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/allergy-to-insect-stings\/)\n      - [Latex Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/latex-allergy\/)\n    - [Testing\/treatments](http:\/\/#)\n      - [Allergy Testing](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/allergy-testing\/)\n      - [Cow’s Milk Reintroduction (Milk Ladder)](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/cows-milk-reintroduction-milk-ladder\/)\n      - [Gradual introduction of Egg (Egg ladder)](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/gradual-introduction-egg-egg-ladder\/)\n      - [Home Milk Challenge](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/home-milk-challenge\/)\n      - [House Dust Mite Avoidance](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/housedustmiteavoidance-2\/)\n      - [Drug Challenge](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/drug-challenge\/)\n      - [Subcutaneous Immunotherapy (SCIT)](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/subcutaneous-immunotherapy-scit\/)\n      - [Sublingual Immunotherapy (SLIT)](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/sublingual-immunotherapy-slit\/)\n  - [Allergy Pathways](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-pathways\/)\n    - [Acute Allergies]()\n      - [Anaphylaxis management pathway](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-pathways\/anaphylaxis-management-pathway\/)\n      - [Infant milk allergy or feeding problem management tool](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-pathways\/infant-milk-allergy-or-feeding-problem-management-tool\/)\n      - [Nut allergy management pathway](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-pathways\/nut-allergy-management-pathway\/)\n      - [Insect venom allergy management pathway](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-pathways\/insect-venom-allergy-management-pathway\/)\n    - [Chronic Allergic Diseases]()\n      - [Chronic urticaria management pathway](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-pathways\/chronic-urticarial-management-pathway\/)\n      - [Eczema management pathway](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-pathways\/eczema-management-plan\/)\n      - [Hay fever management pathway](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-pathways\/hay-fever-management-plan\/)\n  - [Allergy Management Plan](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-mx-plan\/)\n  - [How To Use Medication](https:\/\/allergynorthwest.nhs.uk\/resources\/how-to-use-medication\/)\n  - [For Dietitians](https:\/\/allergynorthwest.nhs.uk\/resources\/for-dietitians\/)\n  - [For school and nurseries](https:\/\/allergynorthwest.nhs.uk\/resources\/for-school\/)\n  - [For Travel](https:\/\/allergynorthwest.nhs.uk\/resources\/for-travel\/)\n- [Engage & Participate](https:\/\/allergynorthwest.nhs.uk\/opportunities\/)\n  - [Educational Events](https:\/\/allergynorthwest.nhs.uk\/opportunities\/educational-events\/)\n    - [Northwest Paediatric Allergy Study Day](https:\/\/allergynorthwest.nhs.uk\/opportunities\/annual-allergy-study-day\/)\n    - [Degrees and courses](https:\/\/allergynorthwest.nhs.uk\/opportunities\/educational-events\/courses-2\/)\n  - [Clinical Trials](https:\/\/allergynorthwest.nhs.uk\/opportunities\/clinical-trials\/)\n  - [Join The Network](https:\/\/allergynorthwest.nhs.uk\/opportunities\/join-the-network\/)\n- [FAQs](https:\/\/allergynorthwest.nhs.uk\/health-professional-zone\/faqs\/)\n\n# Shellfish Allergy\n[![Home](data:image\/svg+xml,%3Csvg%20xmlns='http:\/\/www.w3.org\/2000\/svg'%20viewBox='0%200%200%200'%3E%3C\/svg%3E)![Home](https:\/\/allergynorthwest.nhs.uk\/wp-content\/uploads\/2016\/02\/home.png)](https:\/\/allergynorthwest.nhs.uk\/ \"Go to Home\")\n\n\\> [Resources](https:\/\/allergynorthwest.nhs.uk\/resources\/ \"Go to Resources.\") \\> [Allergy Leaflets](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/ \"Go to Allergy Leaflets.\") \\> [Shellfish Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/shellfish-allergy\/ \"Go to Shellfish Allergy.\")\n\n## How common is shellfish allergy?\nShellfish includes shrimp, prawn, lobster, crab, clam, oyster and mussel. Shellfish allergy is less common in children than in adults. Children who are allergic to shellfish are usually not allergic to white fish, salmon and tuna.\n\n[![img](data:image\/svg+xml,%3Csvg%20xmlns='http:\/\/www.w3.org\/2000\/svg'%20viewBox='0%200%200%200'%3E%3C\/svg%3E) ![img](https:\/\/allergynorthwest.nhs.uk\/wp-content\/uploads\/2016\/10\/pdf-icon40.png)Download Leaflet](https:\/\/allergynorthwest.nhs.uk\/wp-content\/uploads\/2025\/11\/AA-NW-Allergy-Paed-Info-Shellfish.pdf)\n## What are the symptoms of shellfish allergy?\nSymptoms can occur not only after eating shellfish, but also after contact or from breathing the shellfish vapour during cooking or at a fish market. Usually only a hives or “nettle” rash develops. Sometimes as well as a rash, swelling, especially around the face may occur. Some children have an itchy throat; others vomit or can have diarrhoea.\n\nSevere reactions are much less common, but can include difficulty in breathing (with wheeze or swelling in the throat), feeling faint or dizzy. Vapours from the shellfish may trigger an asthma attack in children that are allergic.\n## How serious is shellfish allergy?\nAllergic reactions are usually mild. Severe reactions affecting the child’s breathing can occur, particularly in those with bad asthma who need urgent medical attention.\n\nShellfish allergy can sometimes be confused with shellfish poisoning. This is also called ciguatera poisoning. It occurs in warmer weather because of algae in the water. The poison is not destroyed by cooking the shellfish. It generally occurs in seafood with two shells such as clams, oysters, mussels, and sometimes scallops.\n## Will my child be allergic to other foods?\nShellfish and fish are different. People who are shellfish allergic may be able to eat fish. There are two different types of shellfish: molluscs and crustaceans. Molluscs include mussels, clams, oysters and squid. Crustaceans include prawns, shrimp, lobster, crab and crayfish. People who are allergic to one type of crustacean, such as prawn, are generally allergic to all other crustaceans but may be able to eat molluscs. Your allergist will be able to advise.\n\n## How do we diagnose shellfish allergy?\nThe diagnosis of shellfish allergy is suggested by a history of a reaction after contact with shellfish and a positive skin prick or blood IgE test. An oral challenge is required for a firm diagnosis, as recent evidence suggests that only 10-20% of children with a history of allergy to shellfish and positive allergy tests will react on hospital challenge.\n\nSkin prick tests can be done in clinic provided that the child has not had any antihistamines for a few days. Blood tests are not affected by antihistamines, but the results are only available in a week or so after the clinic appointment.\n## How can my child avoid shellfish?\nShellfish is easy to avoid. Some foods, such as Worcestershire sauce, steak sauce, fried rice, egg rolls, salad dressings, seafood muffaletta sandwiches can have shellfish as hidden ingredients. Cross contamination when buying fresh shellfish over the counter in shops and supermarkets can occur. Some dishes like paella, bouillabaisse, gumbo and frito misto contain lots of different kinds of fish at once, can be difficult to spot. It is useful to avoid such dishes. Some face creams and health supplement can have crushed shells.\n\n## How should you manage a reaction?\n*After a reaction to shellfish, your child should be provided with advice about what to do if they have another reaction. The plan is usually written down – Allergy Management Plan.*\n\n*After a reaction to shellfish, your child should be provided with advice about what to do if they have another reaction. The plan is usually written down – Allergy Management Plan.*\n\n**Mild reaction** – hives, swelling or vomiting, but no breathing problems or faintness:\n\nIf possible, get the child to spit out the food. Give an antihistamine.\n\n**Severe reaction** – **difficulty breathing** (wheezing, noisy breathing, blue colour); **swelling in the throat** (noisy breathing, drooling); feeling faint or dizzy, **looking very pale** (lie the child down with their legs raised).\n\n**Get help straight away and dial 999 stating “anaphylaxis” (ana-fil-ak-sis)**. **If you have an adrenaline pen – use it.**\n## Who needs to know about this allergy?\nIt is important to inform the nursery\/school and any after school clubs. Any other carers will also need to know.\n\n## Is Shellfish allergy life long?\nShellfish allergy is usually life-long. If there has been no reaction for a long time an oral challenge may be suggested.\n\n## Is there a cure?\nThere is no cure for shellfish allergy at present.\n\n### Allergy Leaflets\n- [Food Allergy Leaflets]()\n  - [Peanut Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/peanut-allergy\/)\n  - [Tree Nut Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/tree-nut-allergy\/)\n  - [Cow’s Milk Protein Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/cows-milk-protein-allergy\/)\n  - [Egg Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/egg-allergy\/)\n  - [Wheat Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/wheat-allergy\/)\n  - [Soya bean Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/soya-bean-allergy\/)\n  - [Sesame Seed Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/sesame-seed-allergy\/)\n  - [Fish Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/fish-allergy\/)\n  - [Shellfish Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/shellfish-allergy\/)\n  - [Oral Allergy Syndrome (Food Pollen Syndrome)](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/oral-allergy-syndrome\/)\n- [Other Allergies Leaflets]()\n  - [Chronic Urticaria and Angioedema](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/chronic-urticaria-and-angioedema\/)\n  - [Eczema (Atopic Dermatitis)](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/eczema-atopic-dermatitis\/)\n  - [Hay Fever (Allergic Rhinitis)](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/hay-fever-allergic-rhinitis\/)\n  - [Pet Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/pet-allergy\/)\n  - [Drug Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/drug-allergy\/)\n  - [Allergy to Insect Stings](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/allergy-to-insect-stings\/)\n  - [Latex Allergy](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/latex-allergy\/)\n- [Testing\/treatments]()\n  - [Allergy Testing](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/allergy-testing\/)\n  - [Cow’s Milk Reintroduction (Milk Ladder)](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/cows-milk-reintroduction-milk-ladder\/)\n  - [Gradual introduction of Egg (Egg ladder)](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/gradual-introduction-egg-egg-ladder\/)\n  - [Home Milk Challenge](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/home-milk-challenge\/)\n  - [Drug Challenge](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/drug-challenge\/)\n  - [Subcutaneous Immunotherapy (SCIT)](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/subcutaneous-immunotherapy-scit\/)\n  - [Sublingual Immunotherapy (SLIT)](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/sublingual-immunotherapy-slit\/)\n\nCopyright © 2026 [North West Allergy Network](https:\/\/allergynorthwest.nhs.uk\/). All rights reserved.\n\n- [About Us](https:\/\/allergynorthwest.nhs.uk\/about-us-2\/)\n- [Allergy Leaflets](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-leaflets\/)\n- [Allergy Pathways](https:\/\/allergynorthwest.nhs.uk\/resources\/allergy-pathways\/)\n\n[WordPress Video Lightbox Plugin](http:\/\/www.wonderplugin.com\/wordpress-lightbox\/ \"WordPress Video Lightbox Plugin\")","attrs_readable_markdown":"How common is shellfish allergy?\n\nShellfish includes shrimp, prawn, lobster, crab, clam, oyster and mussel. Shellfish allergy is less common in children than in adults. Children who are allergic to shellfish are usually not allergic to white fish, salmon and tuna.\n\nWhat are the symptoms of shellfish allergy?\n\nSymptoms can occur not only after eating shellfish, but also after contact or from breathing the shellfish vapour during cooking or at a fish market. Usually only a hives or “nettle” rash develops. Sometimes as well as a rash, swelling, especially around the face may occur. Some children have an itchy throat; others vomit or can have diarrhoea.\n\nSevere reactions are much less common, but can include difficulty in breathing (with wheeze or swelling in the throat), feeling faint or dizzy. Vapours from the shellfish may trigger an asthma attack in children that are allergic.\n\nHow serious is shellfish allergy?\n\nAllergic reactions are usually mild. Severe reactions affecting the child’s breathing can occur, particularly in those with bad asthma who need urgent medical attention.\n\nShellfish allergy can sometimes be confused with shellfish poisoning. This is also called ciguatera poisoning. It occurs in warmer weather because of algae in the water. The poison is not destroyed by cooking the shellfish. It generally occurs in seafood with two shells such as clams, oysters, mussels, and sometimes scallops.\n\nWill my child be allergic to other foods?\n\nShellfish and fish are different. People who are shellfish allergic may be able to eat fish. There are two different types of shellfish: molluscs and crustaceans. Molluscs include mussels, clams, oysters and squid. Crustaceans include prawns, shrimp, lobster, crab and crayfish. People who are allergic to one type of crustacean, such as prawn, are generally allergic to all other crustaceans but may be able to eat molluscs. Your allergist will be able to advise.\n\nHow do we diagnose shellfish allergy?\n\nThe diagnosis of shellfish allergy is suggested by a history of a reaction after contact with shellfish and a positive skin prick or blood IgE test. An oral challenge is required for a firm diagnosis, as recent evidence suggests that only 10-20% of children with a history of allergy to shellfish and positive allergy tests will react on hospital challenge.\n\nSkin prick tests can be done in clinic provided that the child has not had any antihistamines for a few days. Blood tests are not affected by antihistamines, but the results are only available in a week or so after the clinic appointment.\n\nHow can my child avoid shellfish?\n\nShellfish is easy to avoid. Some foods, such as Worcestershire sauce, steak sauce, fried rice, egg rolls, salad dressings, seafood muffaletta sandwiches can have shellfish as hidden ingredients. Cross contamination when buying fresh shellfish over the counter in shops and supermarkets can occur. Some dishes like paella, bouillabaisse, gumbo and frito misto contain lots of different kinds of fish at once, can be difficult to spot. It is useful to avoid such dishes. Some face creams and health supplement can have crushed shells.\n\nHow should you manage a reaction?\n\n*After a reaction to shellfish, your child should be provided with advice about what to do if they have another reaction. The plan is usually written down – Allergy Management Plan.*\n\n*After a reaction to shellfish, your child should be provided with advice about what to do if they have another reaction. The plan is usually written down – Allergy Management Plan.*\n\n**Mild reaction** – hives, swelling or vomiting, but no breathing problems or faintness:\n\nIf possible, get the child to spit out the food. Give an antihistamine.\n\n**Severe reaction** – **difficulty breathing** (wheezing, noisy breathing, blue colour); **swelling in the throat** (noisy breathing, drooling); feeling faint or dizzy, **looking very pale** (lie the child down with their legs raised).\n\n**Get help straight away and dial 999 stating “anaphylaxis” (ana-fil-ak-sis)**. **If you have an adrenaline pen – use it.**\n\nWho needs to know about this allergy?\n\nIt is important to inform the nursery\/school and any after school clubs. Any other carers will also need to know.\n\nIs Shellfish allergy life long?\n\nShellfish allergy is usually life-long. If there has been no reaction for a long time an oral challenge may be suggested.\n\nIs there a cure?\n\nThere is no cure for shellfish allergy at present.","meta_canonical":null}

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Boilerpipe Text	How common is shellfish allergy? Shellfish includes shrimp, prawn, lobster, crab, clam, oyster and mussel. Shellfish allergy is less common in children than in adults. Children who are allergic to shellfish are usually not allergic to white fish, salmon and tuna. What are the symptoms of shellfish allergy? Symptoms can occur not only after eating shellfish, but also after contact or from breathing the shellfish vapour during cooking or at a fish market. Usually only a hives or “nettle” rash develops. Sometimes as well as a rash, swelling, especially around the face may occur. Some children have an itchy throat; others vomit or can have diarrhoea. Severe reactions are much less common, but can include difficulty in breathing (with wheeze or swelling in the throat), feeling faint or dizzy. Vapours from the shellfish may trigger an asthma attack in children that are allergic. How serious is shellfish allergy? Allergic reactions are usually mild. Severe reactions affecting the child’s breathing can occur, particularly in those with bad asthma who need urgent medical attention. Shellfish allergy can sometimes be confused with shellfish poisoning. This is also called ciguatera poisoning. It occurs in warmer weather because of algae in the water. The poison is not destroyed by cooking the shellfish. It generally occurs in seafood with two shells such as clams, oysters, mussels, and sometimes scallops. Will my child be allergic to other foods? Shellfish and fish are different. People who are shellfish allergic may be able to eat fish. There are two different types of shellfish: molluscs and crustaceans. Molluscs include mussels, clams, oysters and squid. Crustaceans include prawns, shrimp, lobster, crab and crayfish. People who are allergic to one type of crustacean, such as prawn, are generally allergic to all other crustaceans but may be able to eat molluscs. Your allergist will be able to advise. How do we diagnose shellfish allergy? The diagnosis of shellfish allergy is suggested by a history of a reaction after contact with shellfish and a positive skin prick or blood IgE test. An oral challenge is required for a firm diagnosis, as recent evidence suggests that only 10-20% of children with a history of allergy to shellfish and positive allergy tests will react on hospital challenge. Skin prick tests can be done in clinic provided that the child has not had any antihistamines for a few days. Blood tests are not affected by antihistamines, but the results are only available in a week or so after the clinic appointment. How can my child avoid shellfish? Shellfish is easy to avoid. Some foods, such as Worcestershire sauce, steak sauce, fried rice, egg rolls, salad dressings, seafood muffaletta sandwiches can have shellfish as hidden ingredients. Cross contamination when buying fresh shellfish over the counter in shops and supermarkets can occur. Some dishes like paella, bouillabaisse, gumbo and frito misto contain lots of different kinds of fish at once, can be difficult to spot. It is useful to avoid such dishes. Some face creams and health supplement can have crushed shells. How should you manage a reaction? After a reaction to shellfish, your child should be provided with advice about what to do if they have another reaction. The plan is usually written down – Allergy Management Plan. After a reaction to shellfish, your child should be provided with advice about what to do if they have another reaction. The plan is usually written down – Allergy Management Plan. Mild reaction – hives, swelling or vomiting, but no breathing problems or faintness: If possible, get the child to spit out the food. Give an antihistamine. Severe reaction – difficulty breathing (wheezing, noisy breathing, blue colour); swelling in the throat (noisy breathing, drooling); feeling faint or dizzy, looking very pale (lie the child down with their legs raised). Get help straight away and dial 999 stating “anaphylaxis” (ana-fil-ak-sis) . If you have an adrenaline pen – use it. Who needs to know about this allergy? It is important to inform the nursery/school and any after school clubs. Any other carers will also need to know. Is Shellfish allergy life long? Shellfish allergy is usually life-long. If there has been no reaction for a long time an oral challenge may be suggested. Is there a cure? There is no cure for shellfish allergy at present.
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[COVID 19 vaccination in children](https://allergynorthwest.nhs.uk/covid-19-vaccination-children/) - [Vaccination for children with egg allergy](https://allergynorthwest.nhs.uk/vaccines/about-vaccines/) - [Seasonal Advice](https://allergynorthwest.nhs.uk/about-us-2/seasonal-advice/) - [Links](https://allergynorthwest.nhs.uk/links/) - [Resources](https://allergynorthwest.nhs.uk/resources/) - [Allergy Leaflets](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/) - [Food Allergies]() - [Peanut Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/peanut-allergy/) - [Tree Nut Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/tree-nut-allergy/) - [Cow’s Milk Protein Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/cows-milk-protein-allergy/) - [Egg Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/egg-allergy/) - [Wheat Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/wheat-allergy/) - [Soya bean Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/soya-bean-allergy/) - [Allergy to Legumes & Pulses](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/legume/) - [Sesame Seed Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/sesame-seed-allergy/) - [Fish Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/fish-allergy/) - [Shellfish Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/shellfish-allergy/) - [Oral Allergy Syndrome (Food Pollen Syndrome)](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/oral-allergy-syndrome/) - [FPIES](https://allergynorthwest.nhs.uk/home-patient/managing-allergies/patient-leaflets/fpies/) - [Other Allergies]() - [Chronic Urticaria and Angioedema](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/chronic-urticaria-and-angioedema/) - [Eczema (Atopic Dermatitis)](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/eczema-atopic-dermatitis/) - [Hay Fever (Allergic Rhinitis)](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/hay-fever-allergic-rhinitis/) - [House Dust Mite Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/housedustmiteavoidance/) - [Pet Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/pet-allergy/) - [Drug Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/drug-allergy/) - [Allergy to Insect Stings](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/allergy-to-insect-stings/) - [Latex Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/latex-allergy/) - [Testing/treatments](http://#) - [Allergy Testing](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/allergy-testing/) - [Cow’s Milk Reintroduction (Milk Ladder)](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/cows-milk-reintroduction-milk-ladder/) - [Gradual introduction of Egg (Egg ladder)](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/gradual-introduction-egg-egg-ladder/) - [Home Milk Challenge](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/home-milk-challenge/) - [House Dust Mite Avoidance](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/housedustmiteavoidance-2/) - [Drug Challenge](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/drug-challenge/) - [Subcutaneous Immunotherapy (SCIT)](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/subcutaneous-immunotherapy-scit/) - [Sublingual Immunotherapy (SLIT)](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/sublingual-immunotherapy-slit/) - [Allergy Pathways](https://allergynorthwest.nhs.uk/resources/allergy-pathways/) - [Acute Allergies]() - [Anaphylaxis management pathway](https://allergynorthwest.nhs.uk/resources/allergy-pathways/anaphylaxis-management-pathway/) - [Infant milk allergy or feeding problem management tool](https://allergynorthwest.nhs.uk/resources/allergy-pathways/infant-milk-allergy-or-feeding-problem-management-tool/) - [Nut allergy management pathway](https://allergynorthwest.nhs.uk/resources/allergy-pathways/nut-allergy-management-pathway/) - [Insect venom allergy management pathway](https://allergynorthwest.nhs.uk/resources/allergy-pathways/insect-venom-allergy-management-pathway/) - [Chronic Allergic Diseases]() - [Chronic urticaria management pathway](https://allergynorthwest.nhs.uk/resources/allergy-pathways/chronic-urticarial-management-pathway/) - [Eczema management pathway](https://allergynorthwest.nhs.uk/resources/allergy-pathways/eczema-management-plan/) - [Hay fever management pathway](https://allergynorthwest.nhs.uk/resources/allergy-pathways/hay-fever-management-plan/) - [Allergy Management Plan](https://allergynorthwest.nhs.uk/resources/allergy-mx-plan/) - [How To Use Medication](https://allergynorthwest.nhs.uk/resources/how-to-use-medication/) - [For Dietitians](https://allergynorthwest.nhs.uk/resources/for-dietitians/) - [For school and nurseries](https://allergynorthwest.nhs.uk/resources/for-school/) - [For Travel](https://allergynorthwest.nhs.uk/resources/for-travel/) - [Engage & Participate](https://allergynorthwest.nhs.uk/opportunities/) - 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Shellfish includes shrimp, prawn, lobster, crab, clam, oyster and mussel. Shellfish allergy is less common in children than in adults. Children who are allergic to shellfish are usually not allergic to white fish, salmon and tuna. [![img](data:image/svg+xml,%3Csvg%20xmlns='http://www.w3.org/2000/svg'%20viewBox='0%200%200%200'%3E%3C/svg%3E) ![img](https://allergynorthwest.nhs.uk/wp-content/uploads/2016/10/pdf-icon40.png)Download Leaflet](https://allergynorthwest.nhs.uk/wp-content/uploads/2025/11/AA-NW-Allergy-Paed-Info-Shellfish.pdf) ## What are the symptoms of shellfish allergy? Symptoms can occur not only after eating shellfish, but also after contact or from breathing the shellfish vapour during cooking or at a fish market. Usually only a hives or “nettle” rash develops. Sometimes as well as a rash, swelling, especially around the face may occur. Some children have an itchy throat; others vomit or can have diarrhoea. Severe reactions are much less common, but can include difficulty in breathing (with wheeze or swelling in the throat), feeling faint or dizzy. Vapours from the shellfish may trigger an asthma attack in children that are allergic. ## How serious is shellfish allergy? Allergic reactions are usually mild. Severe reactions affecting the child’s breathing can occur, particularly in those with bad asthma who need urgent medical attention. Shellfish allergy can sometimes be confused with shellfish poisoning. This is also called ciguatera poisoning. It occurs in warmer weather because of algae in the water. The poison is not destroyed by cooking the shellfish. It generally occurs in seafood with two shells such as clams, oysters, mussels, and sometimes scallops. ## Will my child be allergic to other foods? Shellfish and fish are different. People who are shellfish allergic may be able to eat fish. There are two different types of shellfish: molluscs and crustaceans. Molluscs include mussels, clams, oysters and squid. Crustaceans include prawns, shrimp, lobster, crab and crayfish. People who are allergic to one type of crustacean, such as prawn, are generally allergic to all other crustaceans but may be able to eat molluscs. Your allergist will be able to advise. ## How do we diagnose shellfish allergy? The diagnosis of shellfish allergy is suggested by a history of a reaction after contact with shellfish and a positive skin prick or blood IgE test. An oral challenge is required for a firm diagnosis, as recent evidence suggests that only 10-20% of children with a history of allergy to shellfish and positive allergy tests will react on hospital challenge. Skin prick tests can be done in clinic provided that the child has not had any antihistamines for a few days. Blood tests are not affected by antihistamines, but the results are only available in a week or so after the clinic appointment. ## How can my child avoid shellfish? Shellfish is easy to avoid. Some foods, such as Worcestershire sauce, steak sauce, fried rice, egg rolls, salad dressings, seafood muffaletta sandwiches can have shellfish as hidden ingredients. Cross contamination when buying fresh shellfish over the counter in shops and supermarkets can occur. Some dishes like paella, bouillabaisse, gumbo and frito misto contain lots of different kinds of fish at once, can be difficult to spot. It is useful to avoid such dishes. Some face creams and health supplement can have crushed shells. ## How should you manage a reaction? After a reaction to shellfish, your child should be provided with advice about what to do if they have another reaction. The plan is usually written down – Allergy Management Plan. After a reaction to shellfish, your child should be provided with advice about what to do if they have another reaction. The plan is usually written down – Allergy Management Plan. Mild reaction – hives, swelling or vomiting, but no breathing problems or faintness: If possible, get the child to spit out the food. Give an antihistamine. Severe reaction – difficulty breathing (wheezing, noisy breathing, blue colour); swelling in the throat (noisy breathing, drooling); feeling faint or dizzy, looking very pale (lie the child down with their legs raised). Get help straight away and dial 999 stating “anaphylaxis” (ana-fil-ak-sis). If you have an adrenaline pen – use it. ## Who needs to know about this allergy? It is important to inform the nursery/school and any after school clubs. Any other carers will also need to know. ## Is Shellfish allergy life long? Shellfish allergy is usually life-long. If there has been no reaction for a long time an oral challenge may be suggested. ## Is there a cure? There is no cure for shellfish allergy at present. ### Allergy Leaflets - [Food Allergy Leaflets]() - [Peanut Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/peanut-allergy/) - [Tree Nut Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/tree-nut-allergy/) - [Cow’s Milk Protein Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/cows-milk-protein-allergy/) - [Egg Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/egg-allergy/) - [Wheat Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/wheat-allergy/) - [Soya bean Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/soya-bean-allergy/) - [Sesame Seed Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/sesame-seed-allergy/) - [Fish Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/fish-allergy/) - [Shellfish Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/shellfish-allergy/) - [Oral Allergy Syndrome (Food Pollen Syndrome)](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/oral-allergy-syndrome/) - [Other Allergies Leaflets]() - [Chronic Urticaria and Angioedema](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/chronic-urticaria-and-angioedema/) - [Eczema (Atopic Dermatitis)](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/eczema-atopic-dermatitis/) - [Hay Fever (Allergic Rhinitis)](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/hay-fever-allergic-rhinitis/) - [Pet Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/pet-allergy/) - [Drug Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/drug-allergy/) - [Allergy to Insect Stings](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/allergy-to-insect-stings/) - [Latex Allergy](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/latex-allergy/) - [Testing/treatments]() - [Allergy Testing](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/allergy-testing/) - [Cow’s Milk Reintroduction (Milk Ladder)](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/cows-milk-reintroduction-milk-ladder/) - [Gradual introduction of Egg (Egg ladder)](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/gradual-introduction-egg-egg-ladder/) - [Home Milk Challenge](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/home-milk-challenge/) - [Drug Challenge](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/drug-challenge/) - [Subcutaneous Immunotherapy (SCIT)](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/subcutaneous-immunotherapy-scit/) - [Sublingual Immunotherapy (SLIT)](https://allergynorthwest.nhs.uk/resources/allergy-leaflets/sublingual-immunotherapy-slit/) Copyright © 2026 [North West Allergy Network](https://allergynorthwest.nhs.uk/). 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Readable Markdown	How common is shellfish allergy? Shellfish includes shrimp, prawn, lobster, crab, clam, oyster and mussel. Shellfish allergy is less common in children than in adults. Children who are allergic to shellfish are usually not allergic to white fish, salmon and tuna. What are the symptoms of shellfish allergy? Symptoms can occur not only after eating shellfish, but also after contact or from breathing the shellfish vapour during cooking or at a fish market. Usually only a hives or “nettle” rash develops. Sometimes as well as a rash, swelling, especially around the face may occur. Some children have an itchy throat; others vomit or can have diarrhoea. Severe reactions are much less common, but can include difficulty in breathing (with wheeze or swelling in the throat), feeling faint or dizzy. Vapours from the shellfish may trigger an asthma attack in children that are allergic. How serious is shellfish allergy? Allergic reactions are usually mild. Severe reactions affecting the child’s breathing can occur, particularly in those with bad asthma who need urgent medical attention. Shellfish allergy can sometimes be confused with shellfish poisoning. This is also called ciguatera poisoning. It occurs in warmer weather because of algae in the water. The poison is not destroyed by cooking the shellfish. It generally occurs in seafood with two shells such as clams, oysters, mussels, and sometimes scallops. Will my child be allergic to other foods? Shellfish and fish are different. People who are shellfish allergic may be able to eat fish. There are two different types of shellfish: molluscs and crustaceans. Molluscs include mussels, clams, oysters and squid. Crustaceans include prawns, shrimp, lobster, crab and crayfish. People who are allergic to one type of crustacean, such as prawn, are generally allergic to all other crustaceans but may be able to eat molluscs. Your allergist will be able to advise. How do we diagnose shellfish allergy? The diagnosis of shellfish allergy is suggested by a history of a reaction after contact with shellfish and a positive skin prick or blood IgE test. An oral challenge is required for a firm diagnosis, as recent evidence suggests that only 10-20% of children with a history of allergy to shellfish and positive allergy tests will react on hospital challenge. Skin prick tests can be done in clinic provided that the child has not had any antihistamines for a few days. Blood tests are not affected by antihistamines, but the results are only available in a week or so after the clinic appointment. How can my child avoid shellfish? Shellfish is easy to avoid. Some foods, such as Worcestershire sauce, steak sauce, fried rice, egg rolls, salad dressings, seafood muffaletta sandwiches can have shellfish as hidden ingredients. Cross contamination when buying fresh shellfish over the counter in shops and supermarkets can occur. Some dishes like paella, bouillabaisse, gumbo and frito misto contain lots of different kinds of fish at once, can be difficult to spot. It is useful to avoid such dishes. Some face creams and health supplement can have crushed shells. How should you manage a reaction? After a reaction to shellfish, your child should be provided with advice about what to do if they have another reaction. The plan is usually written down – Allergy Management Plan. After a reaction to shellfish, your child should be provided with advice about what to do if they have another reaction. The plan is usually written down – Allergy Management Plan. Mild reaction – hives, swelling or vomiting, but no breathing problems or faintness: If possible, get the child to spit out the food. Give an antihistamine. Severe reaction – difficulty breathing (wheezing, noisy breathing, blue colour); swelling in the throat (noisy breathing, drooling); feeling faint or dizzy, looking very pale (lie the child down with their legs raised). Get help straight away and dial 999 stating “anaphylaxis” (ana-fil-ak-sis). If you have an adrenaline pen – use it. Who needs to know about this allergy? It is important to inform the nursery/school and any after school clubs. Any other carers will also need to know. Is Shellfish allergy life long? Shellfish allergy is usually life-long. If there has been no reaction for a long time an oral challenge may be suggested. Is there a cure? There is no cure for shellfish allergy at present.
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