Pharmacogenomic topic · dashboard states: NM · PM · IM · UM
PGx describes inherited differences in drug handling. AUC measures total exposure, not benefit or toxicity by itself. Ask whether the pathway clears a drug or activates it: slower clearance can raise exposure; slower activation can reduce benefit. Lower inactive-metabolite exposure does not imply lost efficacy.
Dashboard vocabulary: NM = Normal metabolizer; PM = Poor metabolizer; IM = Intermediate metabolizer; UM = Ultrarapid metabolizer. RM = Rapid metabolizer appears only under CYP2C19; EXP = Expresser appears only under CYP3A5. These interface labels do not establish clinical phenotypes for every gene. Prescribing uses the laboratory report, current guidance and monitoring.
Test at a glance
Glucuronidation helps clear bilirubin and certain drugs or metabolites.
Clinical role
Reduced activity slows inactivation of irinotecan's active metabolite, SN-38. Irinotecan and belinostat have label-based PGx recommendations.
Practical pearls
Irinotecan itself may remain unchanged while SN-38 rises.
UGT1A1 clears SN-38; it does not activate irinotecan.
Safety / monitoring
Follow the oncology regimen and product label. Monitor blood counts and diarrhea closely with irinotecan.
Self-check
Which irinotecan-related substance accumulates? SN-38, the active metabolite.
Does every UGT1A1 substrate need PGx-based dosing? No. Recommendations are drug-specific.