Does orforglipron (Foundayo) have any drug interaction with quetiapine (Seroquel), metoprolol, and olanzapine (Zyprexa)?

Drug Interactions Between Orforglipron (Foundayo) and Quetiapine/Olanzapine/Metoprolol

Orforglipron (Foundayo) has no documented direct drug interactions with quetiapine (Seroquel), olanzapine (Zyprexa), or metoprolol based on current FDA labeling and available evidence.

Analysis of Potential Interactions

Orforglipron's Interaction Profile

According to the FDA label for Foundayo, orforglipron is primarily metabolized by CYP3A4 and is a substrate of P-gp and OATP1B1/1B3 transporters 1. The drug interaction studies show:

• No inhibition or induction of CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, or CYP2D6 1
• No inhibition of major transporters (OATP1B1, OATP1B3, P-gp, BCRP, OAT1/3, OCT1/2, MATE1/2K) 1

Individual Drug Considerations

Quetiapine (Seroquel):

• Metabolized primarily via CYP3A4 2
• Since orforglipron does not inhibit or induce CYP3A4, no pharmacokinetic interaction is expected
• Both drugs can cause orthostatic hypotension and sedation 2, requiring clinical monitoring for additive effects

Olanzapine (Zyprexa):

• Metabolized via multiple pathways including glucuronidation and CYP1A2 2
• Orforglipron does not affect these pathways 1
• No pharmacokinetic interaction anticipated
• Both can cause metabolic effects and drowsiness 2, warranting monitoring

Metoprolol:

• Primarily metabolized by CYP2D6 3, 4
• Orforglipron does not inhibit CYP2D6 1
• No direct pharmacokinetic interaction expected
• The guideline notes metoprolol can have additive heart rate effects with other medications 3, but this is not relevant to orforglipron

Important Clinical Considerations

Gastric Emptying Delay

Orforglipron delays gastric emptying, which can affect the absorption rate of oral medications 1. The FDA label shows:

• Maximum effect on absorption occurs after the first dose (acetaminophen Cmax decreased 28%)
• Effect diminishes with repeated dosing 1
• All three medications (quetiapine, olanzapine, metoprolol) are oral agents

Clinical approach: If timing of peak effect is critical (e.g., for acute symptom control), consider administering these medications at least 2 hours before orforglipron, particularly during the first week of treatment.

Pharmacodynamic Monitoring

While no direct drug interactions exist, monitor for:

• Cardiovascular effects: Both antipsychotics can cause QTc prolongation 2, 5; metoprolol affects heart rate 3
• Metabolic parameters: Olanzapine and quetiapine cause weight gain and metabolic changes 2, 6, 7; orforglipron is used for weight loss
• Sedation: Additive sedation possible with quetiapine or olanzapine 2

Common Pitfalls to Avoid

1. Do not confuse CYP enzyme pathways: Metoprolol's CYP2D6 metabolism is irrelevant here since orforglipron doesn't affect this enzyme
2. Do not assume all GLP-1 agonists have identical interaction profiles: Orforglipron's oral formulation and specific metabolism differ from injectable GLP-1 agonists
3. Do not overlook the gastric emptying effect: This is the most clinically relevant consideration, particularly in the first week

Bottom Line

You can safely prescribe orforglipron with quetiapine, olanzapine, and metoprolol without dose adjustments. The only practical consideration is the transient gastric emptying delay during orforglipron initiation, which may slightly delay absorption of these oral medications but does not require intervention in most cases. Monitor for additive pharmacodynamic effects (sedation, metabolic changes, cardiovascular effects) as you would with any polypharmacy regimen.