Dermatology–Allergy Joint Service

The CARD Clinic is a specialized Dermatology–Allergy service dedicated to the evaluation of complex cutaneous adverse drug reactions, with a focus on clarifying the culprit medication and guiding safe future drug use.

Assessments include clinicopathologic correlation, and targeted drug allergy testing (e.g., patch testing, intradermal testing, and drug challenge) when appropriate. A core goal of the clinic is accurate drug allergy label reconciliation to support optimal patient care.

Given the complexity and time-intensive nature of these assessments, all referrals are screened. Referrals will be accepted only when multidisciplinary evaluation and/or drug allergy testing are likely to meaningfully impact management.

Appropriate Referral Criteria

Referrals should meet at least one of the following:

1. Severe or High-Risk Cutaneous Drug Reactions

  • Suspected or confirmed SCAR (e.g., SJS/TEN, DRESS, AGEP)
  • Cutaneous reactions with significant systemic involvement or hospitalization

2. Uncertain Culprit Drug with skin eruption and Clinical Impact

  • Multiple possible offending medications where clarification will affect future prescribing
  • Atypical or diagnostically unclear eruptions not resolved with standard assessment

3. Need for Future Essential Drug Use

  • Cutaneous reaction to a medication that is medically necessary or difficult to substitute
  • Consideration of drug allergy testing, challenge, or re-exposure

Referral Prerequisites

  • Patients must have been previously assessed by Dermatology for the cutaneous eruption
  • The referral question should relate to drug causality and/or the need for drug allergy testing or re-exposure guidance

Not Appropriate for Referral

  • Uncomplicated drug eruptions with a clear culprit and no anticipated need for future use
  • Cases where no drug allergy testing or re-exposure decision-making is anticipated
  • Non–drug-related dermatologic conditions
  • Isolated low-risk drug allergy labels without clinical consequence
  • anaphylaxis

Alternative Referral Pathway

If the primary question relates to medication risk assessment (including timeline reconstruction), polypharmacy, or non-cutaneous adverse drug reactions, referral to the
Clinical Pharmacology and Toxicology Program may be more appropriate. (Clinical Pharmacology Service:  https://cumming.ucalgary.ca/departments/emergency-medicine/programs/clinical-pharmacology-and-toxicology)  

Referral Requirements

To facilitate triage, please include:

  • Complete medication timeline (start/stop dates)
  • Description of eruption and timing relative to drug exposure
  • Clinical photographs (if available)
  • Relevant hospital records, biopsy, or laboratory results

Incomplete referrals may be declined or returned for additional information.