Appendix 1.
Trigger alerts associated with a high probability of a drug-induced laboratory abnormality.
| Category | Logic-based rule |
|---|---|
| Thrombocytopenia (heparin or LMWH) | Heparin/LMWH, platelets <300, and decrease by >50% |
| Supratherapeutic INR (warfarin and DDI) | Warfarin + interacting drug and INR >3.0 |
| Nephrotoxicity | Nephrotoxic agent, SCr >1, and >30% increase in SCr |
| Hepatotoxicity | ALT >200 and total bilirubin >2 and potentially hepatotoxic agent |
| Rapid INR increase (warfarin dose change) | Warfarin dose greater than or equal to the dose on previous day and INR increase >0.5 in 30 h |
| Rapid INR increase (new warfarin start) | New start warfarin and INR increase >0.5 in 30 h |
| Supratherapeutic phenytoin serum concentration | Corrected phenytoin level >20 |
| Hyperkalemia | K >6 and medication linked to hyperkalemia |
| Thrombocytopenia (nonspecific) | Platelets <30 and medication linked with thrombocytopenia |
| Hyperkalemia (ACE-I or ARB) | K >6 and ACE inhibitor or ARB |
| Neutropenia | WBC <4 and medication linked with neutropenia |
| Metabolic acidosis (nonspecific) | Anion gap >14, pH <7.33, and med linked with acidosis |
| Pancreatitis | Amylase >199 or lipase >350 and med linked to pancreatitis |
| Supratherapeutic digoxin serum concentration | Digoxin level >2, and either Mg <1.5 or K <3.2 |
| Metabolic acidosis (topiramate) | Topiramate and serum bicarbonate <15 |
| Hypertriglyceridemia (propofol) | Propofol and triglycerides >400 |
| Hyponatremia | Na <125 and medication linked with hyponatremia |
| Positive antinuclear antibody test (i.e. lupus) | Positive ANA and medication linked with lupus |
| Metabolic acidosis (zonisamide) | Zonisamide, bicarbonate <16 and anion gap <16 |
| Thrombocytopenia (fondaparinux) | Fondaparinux and platelets <100 |
ACE-I, angiotensin-converting-enzyme inhibitor I; ALT, alanine aminotransferase; ANA, antinuclear antibody test; ARB, angiotensin II receptor antagonist; DDI, drug–drug interaction; INR, international normalized ratio; K, potassium; LMWH, low molecular weight heparin; Mg, magnesium; Na, sodium; SCr, serum creatinine; WBC, white blood cell.