Lam DDI for Derm

 Immediate onset mediated by IgE and mastcells/basophils (urticaria, angioedema anaphylaxis) → hypersensitivity

Type I

Delayed onset by IgG-mediated cell destruction (hemolysis, thrombocytopenia, and/or purpura) → cytotoxic 

Type II

Delayed onset caused by IgG drug immune complex deposition and complement activation (serum sickness) → immune-complex

Type III

Delayed onset and T-cell mediated hypersensitivity (contact dermatitis, photoallergic reactions) → delayed

Type IV

Allopurinol SJS gene

HLA-B 5801 (asians)

Carbamazepine SJS gene

HLA-B 1502 (asians)

Drug-induced lupus

Hydralazine, procainamide

Drug induced acne

Lithium (dose related)

Drugs for HLA-B 5701, 5801, 1502

Abacavir, allopurinol, carbamazepine

VKORC1 A/A A/B + CYP2C9 2 and 3

Warfarin → incr bleeding

Which drug is associated with HLA-B 5701 allele?

Abacavir (Ziagen)

Which drug should be tested for HLA-B 5801 allele prior to treatment?

Allopurinol (Zyloprim)

Asian women w/ tegretol what to test on?

HLA-B 1502

Pharmacogenomic testing for which medications?

Abacavir (Ziagen)

Allopurinol (Zyloprim)

Carbamazepine (Tegretol)