Risk of harmful or undesirable physiological response which is specific to an individual and associated with exposure to a substance. Risk of harmful or undesirable physiological response which is specific to an individual and associated with exposure to a substance. If the element is present, it must have either a @value, an @id, or extensions Business identifiers assigned to this AllergyIntolerance by the performer or other systems which remain constant as the resource is updated and propagates from server to server. The clinical status of the allergy or intolerance. Assertion about certainty associated with the propensity, or potential risk, of a reaction to the identified substance (including pharmaceutical product). The verification status pertains to the allergy or intolerance, itself, not to any specific AllergyIntolerance attribute. Identification of the underlying physiological mechanism for the reaction risk. Category of the identified substance. Estimate of the potential clinical harm, or seriousness, of the reaction to the identified substance. Code for an allergy or intolerance statement (either a positive or a negated/excluded statement). This may be a code for a substance or pharmaceutical product that is considered to be responsible for the adverse reaction risk (e.g., "Latex"), an allergy or intolerance condition (e.g., "Latex allergy"), or a negated/excluded code for a specific substance or class (e.g., "No latex allergy") or a general or categorical negated statement (e.g., "No known allergy", "No known drug allergies"). Note: the substance for a specific reaction may be different from the substance identified as the cause of the risk, but it must be consistent with it. For instance, it may be a more specific substance (e.g. a brand medication) or a composite product that includes the identified substance. It must be clinically safe to only process the 'code' and ignore the 'reaction.substance'. If a receiving system is unable to confirm that AllergyIntolerance.reaction.substance falls within the semantic scope of AllergyIntolerance.code, then the receiving system should ignore AllergyIntolerance.reaction.substance. The patient who has the allergy or intolerance. The encounter when the allergy or intolerance was asserted. Estimated or actual date, date-time, or age when allergy or intolerance was identified. The recordedDate represents when this particular AllergyIntolerance record was created in the system, which is often a system-generated date. Individual who recorded the record and takes responsibility for accurately recording its content. The source of the information about the allergy that is recorded. Represents the date and/or time of the last known occurrence of a reaction event. Additional narrative about the propensity for the Adverse Reaction, not captured in other fields. Details about each adverse reaction event linked to exposure to the identified substance. Risk of harmful or undesirable physiological response which is specific to an individual and associated with exposure to a substance. Identification of the specific substance (or pharmaceutical product) considered to be responsible for the Adverse Reaction event. Note: the substance for a specific reaction may be different from the substance identified as the cause of the risk, but it must be consistent with it. For instance, it may be a more specific substance (e.g. a brand medication) or a composite product that includes the identified substance. It must be clinically safe to only process the 'code' and ignore the 'reaction.substance'. If a receiving system is unable to confirm that AllergyIntolerance.reaction.substance falls within the semantic scope of AllergyIntolerance.code, then the receiving system should ignore AllergyIntolerance.reaction.substance. Clinical symptoms and/or signs that are observed or associated with the adverse reaction event. Text description about the reaction as a whole, including details of the manifestation if required. Record of the date and/or time of the onset of the Reaction. Clinical assessment of the severity of the reaction event as a whole, potentially considering multiple different manifestations. Identification of the route by which the subject was exposed to the substance. Additional text about the adverse reaction event not captured in other fields. Low Risk High Risk Unable to Assess Risk If the element is present, it must have either a @value, an @id, or extensions Food Medication Environment Biologic If the element is present, it must have either a @value, an @id, or extensions Mild Moderate Severe If the element is present, it must have either a @value, an @id, or extensions