Fig. 1

Actions that must be completed by prescribers and pharmacists when an alert for a very severe drug–drug interaction is generated. Panel A: general workflow diagram of very severe drug–drug interaction alerts. Panel B: workflow diagram using a specific example categorized as a very severe drug–drug interaction: co-prescription of a non-vitamin K oral anticoagulant and a low molecular weight heparin. Blue: actions that must be taken by the prescriber. Grey: actions that must be taken by the pharmacist. DDI, drug–drug interaction, NOAC, non-vitamin K oral anticoagulant; LMWH, low molecular weight heparin