Can I take Monjouro (generic name not specified) with Toujeo (insulin glargine) Max SoloStar 300 UNIT/ML Solution Pen-injector at a dose of 84 units once a day subcutaneously?

Can Mounjaro Be Taken with Toujeo?

Yes, Mounjaro (tirzepatide, a dual GIP/GLP-1 receptor agonist) can be safely combined with Toujeo (insulin glargine 300 units/mL), and this combination is explicitly supported by current diabetes guidelines as an effective strategy to improve glycemic control while minimizing weight gain and hypoglycemia risk. 1

Evidence-Based Rationale for Combination Therapy

The combination of basal insulin and GLP-1 receptor agonists (which includes dual GIP/GLP-1 agonists like Mounjaro) has potent glucose-lowering actions with less weight gain and hypoglycemia compared to intensified insulin regimens alone. 1 This approach is particularly valuable when basal insulin has been titrated but A1C remains above target.

When to Add GLP-1/GIP Agonists to Basal Insulin

The American Diabetes Association recommends considering the addition of a GLP-1 receptor agonist (or dual GIP/GLP-1 RA like Mounjaro) to basal insulin when: 1

• Basal insulin has been optimized (fasting glucose 80-130 mg/dL) but A1C remains above target after 3-6 months
• Basal insulin dose approaches or exceeds 0.5 units/kg/day without achieving glycemic goals
• Postprandial hyperglycemia persists despite adequate fasting glucose control
• Weight gain or hypoglycemia risk needs to be minimized

Critical Evaluation of Your Current Regimen

Assessing for Overbasalization

Your current Toujeo dose of 84 units daily warrants careful evaluation for "overbasalization," which occurs when basal insulin is escalated beyond optimal levels without addressing postprandial hyperglycemia. 1 Clinical signals that should prompt this evaluation include: 1

• Basal insulin dose exceeding 0.5 units/kg/day (for a 70 kg patient, this would be >35 units; for an 84 kg patient, >42 units)
• High bedtime-to-morning glucose differential (≥50 mg/dL)
• Hypoglycemia episodes (aware or unaware)
• High glycemic variability

If you weigh less than 168 kg (370 lbs), your 84-unit daily dose exceeds the 0.5 units/kg/day threshold, suggesting that adding Mounjaro rather than further increasing Toujeo is the appropriate next step. 1

Practical Implementation Strategy

Medication Adjustments When Adding Mounjaro

When initiating Mounjaro with existing basal insulin: 1

• Continue your current Toujeo dose initially while starting Mounjaro at its standard titration schedule
• Monitor fasting and postprandial glucose closely during the first 2-4 weeks
• Be prepared to reduce Toujeo by 10-20% if hypoglycemia occurs, as Mounjaro will improve both fasting and postprandial glucose control 1
• Maintain metformin therapy unless contraindicated, as it remains the foundation of type 2 diabetes management 1

Monitoring Requirements

Daily self-monitoring of blood glucose is essential during this transition period, with particular attention to: 1

• Fasting glucose levels (target 80-130 mg/dL)
• Pre-meal glucose readings
• Any symptoms of hypoglycemia
• Reassessment every 3-6 months with A1C monitoring

Alternative Consideration: Prandial Insulin

If postprandial hyperglycemia is the primary issue and Mounjaro is not accessible or preferred, adding prandial insulin coverage is an alternative approach. 1 This would involve starting with 4 units of rapid-acting insulin before the largest meal or 10% of your current basal dose (approximately 8 units). 1

However, the combination of basal insulin plus GLP-1/GIP agonist (Mounjaro) offers advantages over basal-bolus insulin regimens, including less hypoglycemia, weight loss rather than weight gain, and simpler dosing. 1

Common Pitfalls to Avoid

• Do not continue escalating Toujeo beyond 0.5-1.0 units/kg/day without addressing postprandial hyperglycemia, as this leads to overbasalization with increased hypoglycemia risk and suboptimal control 1
• Do not discontinue metformin when adding or intensifying injectable therapy unless contraindicated 1
• Do not delay the addition of adjunctive therapy (like Mounjaro) when basal insulin alone is insufficient to achieve glycemic targets 1

Safety Considerations

Both medications can be administered on the same day without drug-drug interactions. Mounjaro is typically injected once weekly, while Toujeo is administered once daily. The primary safety concern is hypoglycemia, which is actually reduced with this combination compared to insulin intensification alone. 1