What is the half-life of Mounjaro (tirzepatide)?

Half-Life of Mounjaro (Tirzepatide)

The half-life of Mounjaro (tirzepatide) is approximately 5 days (116.7 hours), which enables once-weekly subcutaneous dosing. 1

Pharmacokinetic Details

The elimination half-life of tirzepatide is specifically reported as:

• Approximately 5 days in FDA labeling 1
• 116.7 hours (approximately 4.9 days) in clinical guidelines 2

This extended half-life is achieved through albumin binding facilitated by a C20 fatty diacid moiety attached to the peptide backbone 1. The apparent population mean clearance is 0.061 L/h 1.

Clinical Implications

Steady-state concentrations are reached after 4 weeks of once-weekly administration, meaning the drug accumulates to therapeutic levels over the first month of treatment 1.

Key Practical Considerations:

• Dosing frequency: The 5-day half-life supports once-weekly subcutaneous injection 2
• Missed doses: If treatment is interrupted, patients must restart at the lowest dose and re-titrate, as the body needs time to re-acclimate 2
• Overdose management: In case of overdose, a period of observation and supportive treatment may be necessary, accounting for the approximately 5-day half-life 1
• Perioperative considerations: Due to the 5-day half-life, some guidelines recommend stopping tirzepatide one week before elective procedures to minimize gastric emptying effects 3

The long half-life distinguishes tirzepatide from shorter-acting GLP-1 receptor agonists and is critical for understanding both its therapeutic dosing schedule and management of adverse effects.