MOUNJARO

Clinical safety rating: caution

Comprehensive clinical and safety monograph for MOUNJARO (MOUNJARO).

How it works

Tirzepatide is a once-weekly dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist. It activates GIP and GLP-1 receptors, potentiating glucose-dependent insulin secretion from pancreatic beta cells, reducing glucagon secretion, slowing gastric emptying, and promoting satiety via hypothalamic appetite regulation.

What the body does with it

Metabolism	Undergoes proteolytic cleavage of the peptide backbone and beta-oxidation of the C20 fatty diacid moiety via multiple enzymes, including CYP450? (minimal CYP-mediated metabolism). Mainly metabolized by peptidases and fatty acid oxidation pathways.
Excretion	Primarily eliminated via proteolytic degradation, with the parent drug not significantly excreted renally or in feces. Small amounts of metabolites may be excreted in urine and feces.
Half-life	Terminal elimination half-life is approximately 5 days (range 4-6 days), supporting once-weekly dosing. Achieves steady-state after 4-5 weeks.
Protein binding	Highly bound to albumin (approximately 99%).
Volume of Distribution	Approximately 7.5 L (0.1 L/kg for a 75 kg individual). Indicates limited extravascular distribution.
Bioavailability	Subcutaneous: Approximately 80-95%.
Onset of Action	Subcutaneous: Glycemic effects observed within 1-2 weeks; maximal glucose-lowering effects typically seen by 4-8 weeks.
Duration of Action	Subcutaneous: Duration of action is approximately 1 week, consistent with half-life. Glycemic control maintained over the weekly dosing interval.

Classification & Brands

Dosing & administration

Subcutaneous injection once weekly. Starting dose: 2.5 mg for 4 weeks, then increase to 5 mg for at least 4 weeks. For additional glycemic control, may increase in 2.5 mg increments after at least 4 weeks on current dose. Maximum dose: 15 mg once weekly.

Dosage form	SOLUTION
Renal impairment	No dose adjustment required for mild to moderate renal impairment (eGFR >=30 mL/min/1.73 m2). Not recommended in severe renal impairment (eGFR <30 mL/min/1.73 m2) or end-stage renal disease due to lack of data.
Liver impairment	No dose adjustment required for mild hepatic impairment (Child-Pugh Class A). Not recommended in moderate to severe hepatic impairment (Child-Pugh Class B or C) due to limited data.
Pediatric use	Safety and effectiveness in pediatric patients (<18 years) have not been established. No recommended dose.
Geriatric use	No specific dose adjustment required for elderly patients based on age alone. Use caution due to potential for renal function decline; monitor renal function.

Use during pregnancy

1st trimester	Consult provider
2nd trimester	Consult provider
3rd trimester	Consult provider

Clinical note

Comprehensive clinical and safety monograph for MOUNJARO (MOUNJARO).

Breastfeeding	No human data on presence in breast milk. Based on molecular weight (~4 kDa) and high protein binding, expected to be low. No M/P ratio available. Caution recommended; consider alternative agents.
Teratogenic Risk	First trimester: Based on animal studies, there is a risk of fetal harm due to drug-induced maternal weight loss and reduced food intake. No adequate human studies. Second and third trimesters: Potential risk of fetal hypoglycemia and altered fetal growth. Avoid use in all trimesters unless clearly needed.

Warnings & precautions

■ FDA Black Box Warning

WARNING: RISK OF THYROID C-TUMORS. Tirzepatide caused dose-dependent and treatment-duration-dependent thyroid C-cell tumors (adenomas and carcinomas) in male and female rats. It is contraindicated in patients with a personal or family history of medullary thyroid carcinoma (MTC) and in patients with Multiple Endocrine Neoplasia syndrome type 2 (MEN 2).

Side Effect Profile

Serious Effects

Absolute Contraindications

Personal or family history of medullary thyroid carcinoma (MTC); Multiple Endocrine Neoplasia syndrome type 2 (MEN 2); hypersensitivity to tirzepatide or any excipients.

Clinical Precautions

Precautions

Pancreatitis (acute, hemorrhagic, necrotizing); hypoglycemia, especially with sulfonylureas or insulin; acute kidney injury; diabetic retinopathy complications in type 2 diabetes (with rapid improvement in glucose control); hypersensitivity reactions (angioedema, anaphylaxis); gallbladder disease (cholelithiasis, cholecystitis); severe gastrointestinal adverse reactions; increased heart rate; suicidal behavior or ideation; acute pancreatitis; thyroid C-cell tumors; pulmonary aspiration during general anesthesia due to delayed gastric emptying.

Clinical Tips & Counseling

Drug interactions

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MOUNJARO

Clinical safety rating: caution

Comprehensive clinical and safety monograph for MOUNJARO (MOUNJARO).

How it works

What the body does with it

Metabolism	Undergoes proteolytic cleavage of the peptide backbone and beta-oxidation of the C20 fatty diacid moiety via multiple enzymes, including CYP450? (minimal CYP-mediated metabolism). Mainly metabolized by peptidases and fatty acid oxidation pathways.
Excretion	Primarily eliminated via proteolytic degradation, with the parent drug not significantly excreted renally or in feces. Small amounts of metabolites may be excreted in urine and feces.
Half-life	Terminal elimination half-life is approximately 5 days (range 4-6 days), supporting once-weekly dosing. Achieves steady-state after 4-5 weeks.
Protein binding	Highly bound to albumin (approximately 99%).
Volume of Distribution	Approximately 7.5 L (0.1 L/kg for a 75 kg individual). Indicates limited extravascular distribution.
Bioavailability	Subcutaneous: Approximately 80-95%.
Onset of Action	Subcutaneous: Glycemic effects observed within 1-2 weeks; maximal glucose-lowering effects typically seen by 4-8 weeks.
Duration of Action	Subcutaneous: Duration of action is approximately 1 week, consistent with half-life. Glycemic control maintained over the weekly dosing interval.

Classification & Brands

Dosing & administration

Dosage form	SOLUTION
Renal impairment	No dose adjustment required for mild to moderate renal impairment (eGFR >=30 mL/min/1.73 m2). Not recommended in severe renal impairment (eGFR <30 mL/min/1.73 m2) or end-stage renal disease due to lack of data.
Liver impairment	No dose adjustment required for mild hepatic impairment (Child-Pugh Class A). Not recommended in moderate to severe hepatic impairment (Child-Pugh Class B or C) due to limited data.
Pediatric use	Safety and effectiveness in pediatric patients (<18 years) have not been established. No recommended dose.
Geriatric use	No specific dose adjustment required for elderly patients based on age alone. Use caution due to potential for renal function decline; monitor renal function.

Use during pregnancy

1st trimester	Consult provider
2nd trimester	Consult provider
3rd trimester	Consult provider

Clinical note

Comprehensive clinical and safety monograph for MOUNJARO (MOUNJARO).

Breastfeeding	No human data on presence in breast milk. Based on molecular weight (~4 kDa) and high protein binding, expected to be low. No M/P ratio available. Caution recommended; consider alternative agents.
Teratogenic Risk	First trimester: Based on animal studies, there is a risk of fetal harm due to drug-induced maternal weight loss and reduced food intake. No adequate human studies. Second and third trimesters: Potential risk of fetal hypoglycemia and altered fetal growth. Avoid use in all trimesters unless clearly needed.

Warnings & precautions

■ FDA Black Box Warning

Side Effect Profile

Serious Effects

Absolute Contraindications

Personal or family history of medullary thyroid carcinoma (MTC); Multiple Endocrine Neoplasia syndrome type 2 (MEN 2); hypersensitivity to tirzepatide or any excipients.