What is the correct dose to restart Mounjaro (tirzepatide) in a patient with type 2 diabetes after surgery?

Restarting Mounjaro After Surgery

Resume Mounjaro at your previous maintenance dose once you are eating and drinking normally after surgery, typically within 24-48 hours for outpatient procedures or when capillary ketones are <0.6 mmol/L for inpatients. 1

Immediate Post-Operative Period

Standard Restart Protocol

• For patients discharged on the day of surgery: Restart Mounjaro once eating and drinking normally, usually 24-48 hours after the procedure 2
• For patients staying in hospital: Resume Mounjaro once eating and drinking normally AND capillary ketones are <0.6 mmol/L 2
• Return to your pre-surgery maintenance dose (5 mg, 7.5 mg, 10 mg, 12.5 mg, or 15 mg weekly) - do NOT restart at the 2.5 mg initiation dose 1

Timing Considerations

• If you miss your regularly scheduled dose during the perioperative period, administer Mounjaro as soon as possible within 4 days (96 hours) after the missed dose 1
• If more than 4 days have passed since your missed dose, skip it and administer the next dose on your regularly scheduled day 1
• Ensure at least 3 days (72 hours) between doses when resuming 1

Critical Safety Considerations

Pre-Operative Withholding

• Mounjaro should have been withheld the day before and day of your procedure to reduce risk of delayed gastric emptying and aspiration 2
• The medication's effects on gastric emptying can persist even after withholding, requiring careful monitoring 2

Post-Operative Monitoring Requirements

• Avoid prolonged fasting periods - adhere to recommended fasting guidelines to prevent ketone generation 2
• Ensure adequate hydration during the perioperative period as a mitigation strategy 2
• Monitor for gastrointestinal symptoms (nausea, vomiting, diarrhea) which may be more pronounced when restarting 1, 3

Special Clinical Situations

If You Required Insulin During Surgery

• If you needed IV insulin during surgery, Mounjaro can be restarted once you transition back to subcutaneous insulin or oral intake 4, 5
• Continue any basal insulin that was prescribed during hospitalization until Mounjaro's glucose-lowering effects resume (typically within 1-2 weeks) 3, 6
• Coordinate with your endocrinologist regarding insulin dose adjustments as Mounjaro's effects return 4, 5

If You Were on Metformin

• Resume metformin when restarting Mounjaro unless contraindicated (creatinine clearance <60 mL/min) 5
• The combination of Mounjaro and metformin provides complementary glucose-lowering effects 3, 7

Common Pitfalls to Avoid

• Do NOT restart at the 2.5 mg initiation dose - this is only for treatment-naive patients and will result in inadequate glycemic control 1
• Do NOT delay restarting beyond 48 hours if eating normally, as this prolongs hyperglycemia exposure and increases complication risk 2, 5
• Do NOT restart if still experiencing significant nausea/vomiting - wait until gastrointestinal symptoms resolve and oral intake is adequate 2, 1
• Do NOT restart if on a very low-energy/liver reduction diet - Mounjaro should remain discontinued until normal caloric intake resumes 2

When to Contact Your Healthcare Provider

• If blood glucose remains >180 mg/dL (10 mmol/L) for more than 48 hours after restarting Mounjaro 2, 5
• If you experience severe gastrointestinal symptoms (persistent vomiting, inability to maintain hydration) after restarting 1
• If you develop signs of ketoacidosis (nausea, vomiting, abdominal pain, altered mental status) - check ketones immediately 2
• If you are uncertain about when to restart due to prolonged poor oral intake or complications 2, 5

Expected Outcomes

• Mounjaro's full glucose-lowering effects typically resume within 1-2 weeks of restarting at your maintenance dose 3, 6
• Weight loss effects will continue once normal eating patterns resume 3, 7, 6
• Most patients tolerate restarting well, with gastrointestinal side effects being mild to moderate if they occur 8, 6