{"id":"5471c532-1981-53e5-8be7-1ce50666406e","stable_key":"7de430a5-1a36-5231-b931-35cc01d8f3bf:apap-twenty-percent-cross-react","predicate":"causes","statement":"Of 256 patients with a history of recent pseudoallergic skin reactions caused by non-steroidal anti-inflammatory drugs who underwent elective oral challenges, 48 or 19% reacted to acetaminophen or nimesulide, with similar proportions among those with chronic urticaria at 23% and otherwise normal subjects with a history of aspirin-induced urticaria at 19% while pyrazolone-intolerant patients showed the lowest number at 4%, aspirin intolerance was a risk factor for acetaminophen or nimesulide induced urticaria with a relative risk of 5.4, a history of anaphylactoid reactions carried a relative risk of 5.7, and atopy raised reactivity to nimesulide from 9 to 23%.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"89e252bb-eafb-543d-b01f-5ab21672221e","mechanism_event_label":"One patient in five who reacts to aspirin also reacts to paracetamol, so it is not automatically the safe substitute.","subject":{"id":"a901be21-7915-543c-ac67-c39ef72b0d03","slug":"acetaminophen","display_name":"Paracetamol","entity_type_key":"drug"},"object":{"id":"5643975a-0dd2-5860-8c67-eeae0d9e53d1","slug":"urticaria-angioedema","display_name":"Urticaria and angioedema","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"89e252bb-eafb-543d-b01f-5ab21672221e","stable_key":"7de430a5-1a36-5231-b931-35cc01d8f3bf:apap-twenty-percent-cross-react-event","event_type":"observed_intervention","label":"One patient in five who reacts to aspirin also reacts to paracetamol, so it is not automatically the safe substitute.","description":"Of 256 patients with a history of recent pseudoallergic skin reactions caused by non-steroidal anti-inflammatory drugs who underwent elective oral challenges, 48 or 19% reacted to acetaminophen or nimesulide, with similar proportions among those with chronic urticaria at 23% and otherwise normal subjects with a history of aspirin-induced urticaria at 19% while pyrazolone-intolerant patients showed the lowest number at 4%, aspirin intolerance was a risk factor for acetaminophen or nimesulide induced urticaria with a relative risk of 5.4, a history of anaphylactoid reactions carried a relative risk of 5.7, and atopy raised reactivity to nimesulide from 9 to 23%.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"3f745fea-645b-5b10-8a9a-989940e5b826","slug":"aspirin-sensitive-subject","display_name":"Subject with aspirin-sensitive asthma or aspirin-induced urticaria","entity_type_key":"cellular_process"},"role":"studied_group","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"d7a404d3-86ed-532b-9333-3d8c5ce60135","slug":"nimesulide","display_name":"Nimesulide","entity_type_key":"drug"},"role":"comparator_drug","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"8ac405bf-3ea0-539a-8e5e-abf503dc7081","slug":"aspirin","display_name":"Aspirin / acetylsalicylic acid","entity_type_key":"drug"},"role":"index_drug","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"a901be21-7915-543c-ac67-c39ef72b0d03","slug":"acetaminophen","display_name":"Paracetamol","entity_type_key":"drug"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"5643975a-0dd2-5860-8c67-eeae0d9e53d1","slug":"urticaria-angioedema","display_name":"Urticaria and angioedema","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"biomarker_context","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/paracetamol-research/10400483.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"7ea713edb6955db38992c5372794d93c0d52f841d3f8897817286f7f66d28605\", \"start_char\": 0, \"end_char\": 2662, \"text_sha256\": \"7ea713edb6955db38992c5372794d93c0d52f841d3f8897817286f7f66d28605\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Elective oral challenges in 256 patients with a history of pseudoallergic skin reactions to non-steroidal anti-inflammatory drugs","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Increasing doses of acetaminophen and nimesulide across three patient groups","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"A large challenge series that puts a rate on the cross-reactivity and identifies risk factors. 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Patients were selected for a history of reacting, so the rates apply to that population and not to the general one.\nexposure: Increasing doses of acetaminophen and nimesulide across three patient groups\nevidence_span: {\"source_cache\": \"artifacts/paracetamol-research/10400483.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"7ea713edb6955db38992c5372794d93c0d52f841d3f8897817286f7f66d28605\", \"start_char\": 0, \"end_char\": 2662, \"text_sha256\": \"7ea713edb6955db38992c5372794d93c0d52f841d3f8897817286f7f66d28605\"}\n[apap-p10400483] Risk factors for acetaminophen and nimesulide intolerance in patients with NSAID-induced skin disorders. 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