DRUG DESENSITIZATION

To encourage an allergy reconciliation process to ensure allergy documentation is accurate and complete for drug desensitization; further,

To advocate for pharmacist involvement in the interdisciplinary development of institutional drug desensitization policies and procedures; further,

To support the creation and implementation of drug desensitization order sets and safeguards in the electronic health record to minimize potential error risk; further,

To recommend appropriate allocation of resources needed for the drug desensitization process, including adequate availability of allergic reaction management resources near the desensitization location; further,

To support the education and training of pharmacists regarding allergy reconciliation, drug desensitization processes, and allergic reaction prevention and management; further,

To recommend patient education and appropriate documentation in the electronic health record of the outcomes of the drug desensitization process.

Rationale

Only about 5-10% of all drug-related adverse events are allergic in nature. Patients are often labeled with an allergy on the basis of a side effect or intolerances such as headache or gastrointestinal disturbance. Allergen misidentification and documentation can be detrimental to patient care by preventing the use of optimal drugs or by causing re-exposure to a true allergen. However, when a patient has a true allergy, and the drug is required for treatment, drug desensitization is often the next step in patient care.

Drug desensitization is a procedure that transiently alters a patient’s immune response to a drug to permit an allergic patient to receive the sensitizing drug safely. Approaches to desensitization are often drug- and protocol-specific and vary widely (e.g., in the length of sensitization based on patient-specific factors such as immune response, body composition, height, and weight). This approach to patient care is not without risk or controversy, as the mechanism of drug desensitization is not completely understood but the procedure is often deemed essential to patient care when a specific drug is the only appropriate therapy for a patient. Drug concentrations and dilutions are often not standardized, and depending on the drug, can be a source of significant error, particularly with high-risk medications such as chemotherapeutic agents. Sources of error that have been cited in the literature include compounding errors, order entry into the electronic health record, lack of standardized order sets, variability in concentrations of sensitizing doses, allergic reaction prevention, and documentation of desensitization outcomes.