Drug Interactions

Cleo can check for drug-drug interactions between medications. Ask about a single drug to see all known interactions, or check multiple drugs to see if they interact with each other.

How It Works

Cleo has a local database of 38,000+ drug interactions from two clinical sources:

• High-priority interactions — Expert-curated interactions from the ONC High Priority list that pose significant clinical risk
• Moderate interactions — Comprehensive interactions from DrugBank for broader coverage

When you ask about interactions, Cleo checks this database instantly—no external API calls needed.

Asking About Interactions

In the Cleo side panel, you can ask questions like:

Question	What Cleo Does
”What drugs interact with warfarin?”	Lists all known interactions for warfarin
”Does metformin interact with lisinopril?”	Checks if these two drugs interact
”Check drug interactions for this patient”	Reviews the patient’s medication list
”Are there any interactions between aspirin, metoprolol, and atorvastatin?”	Checks all pairwise interactions

Tip

Cleo converts drug names to standard identifiers automatically. You can use brand names, generic names, or a mix of both.

Understanding Results

Single Drug Lookup

When you ask about interactions for one drug, Cleo returns up to 100 known interactions, sorted by severity:

Warfarin Interactions (showing 15 of 47):

⚠️ HIGH PRIORITY:
  • Aspirin — Increased bleeding risk
  • Fluconazole — Enhanced anticoagulant effect

⚡ MODERATE:
  • Atorvastatin — May increase warfarin effect
  • Omeprazole — Variable effect on INR
  • Acetaminophen — May increase INR with regular use

Multiple Drug Check

When checking interactions between specific drugs:

Checking: Warfarin, Aspirin, Metoprolol

Found 1 interaction:

⚠️ Warfarin ↔ Aspirin (HIGH)
   Source: ONCHigh
   Both affect clotting; increased bleeding risk

Severity Levels

Severity	Description
High	Expert-curated interactions with significant clinical risk. Requires careful consideration.
Moderate	Documented interactions that may require monitoring or dose adjustment.

Common Use Cases

New Prescription

Before prescribing a new medication, check if it interacts with the patient’s current medications:

“Does [new drug] interact with any of this patient’s medications?”

Cleo will cross-reference the new drug against the patient’s active medication list.

Medication Review

During a medication reconciliation or annual review:

“Check for drug interactions”

Cleo reviews all medications on the patient’s list and flags any interactions.

Drug Reference

When you need to know what a drug interacts with in general:

“What are the interactions for amiodarone?”

Useful when considering a medication class for a patient with a complex regimen.

Data Sources

Interaction data comes from two curated sources:

Source	Focus	Entries
ONC High Priority	Expert-curated high-risk interactions identified by the Office of the National Coordinator	~2,000
DrugBank	Comprehensive drug interaction database	~37,000

Drugs are mapped to standard RXCUI identifiers from the National Library of Medicine’s RxNorm database.

Limitations

• Database scope — While comprehensive, this database may not include every possible interaction
• Clinical judgment — Results are informational; always apply clinical judgment
• Severity context — Interaction severity may vary based on patient factors (age, renal function, etc.)

Note

Drug interactions provide clinical decision support, not definitive guidance. Always consider the full clinical picture when making prescribing decisions.