Indications

Adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus.
Limitations of use:
- Not studied in patients with history of pancreatitis.
- Not indicated for type 1 diabetes mellitus.

Pharmacology

Tirzepatide is a dual GIP receptor and GLP-1 receptor agonist.
Modified peptide (39 amino acids) with fatty diacid moiety for albumin binding → prolonged half-life.
Enhances first- and second-phase insulin secretion, reduces glucagon levels in a glucose-dependent manner.

Dosage & Administration

Route: Subcutaneous injection.
Starting dose: 2.5 mg once weekly (initiation only, not for glycemic control).
After 4 weeks: increase to 5 mg once weekly.
Further increases: in 2.5 mg increments every ≥4 weeks, up to max 15 mg once weekly.
Missed dose: administer within 4 days; if >4 days, skip and resume regular schedule.
Weekly administration day can be changed if ≥3 days between doses.
Injection sites: abdomen, thigh, upper arm (rotate sites).
Do not mix with insulin; if used together, inject separately in same region but not adjacent.
Do not freeze; protect pre-filled syringes from light; inspect visually before use.

Interactions

Reduce dose of insulin or secretagogues (e.g., sulfonylureas) to lower hypoglycemia risk.
Delays gastric emptying → may affect absorption of oral drugs (e.g., warfarin).
Oral contraceptives: advise switching to non-oral or add barrier method for 4 weeks after initiation and after each dose escalation.
Non-oral contraceptives not affected.

Contraindications

Side Effects

Common: nausea, diarrhea, decreased appetite, vomiting, constipation, dyspepsia, abdominal pain.

Pregnancy & Lactation

Precautions & Warnings

Use in Special Populations

Overdose Effects