Last reviewed 2026-04-23 · How we verify

Metformin + Janufer (Janumet)

Metformin reduces hepatic glucose production and improves insulin sensitivity, while sitagliptin (Januvia) inhibits DPP-4 to increase incretin-mediated insulin secretion and reduce glucagon.

Metformin reduces hepatic glucose production and improves insulin sensitivity, while sitagliptin (Januvia) inhibits DPP-4 to increase incretin-mediated insulin secretion and reduce glucagon. Used for Type 2 diabetes mellitus.

At a glance

Mechanism of action

Janumet combines two complementary antidiabetic agents with different mechanisms. Metformin acts primarily on the liver to decrease glucose output and enhance peripheral insulin sensitivity. Sitagliptin is a dipeptidyl peptidase-4 (DPP-4) inhibitor that prolongs the action of endogenous GLP-1 and GIP, thereby stimulating glucose-dependent insulin secretion and suppressing glucagon secretion in a glucose-dependent manner.

Approved indications

• Type 2 diabetes mellitus

Common side effects

• Gastrointestinal disturbance (nausea, diarrhea, abdominal pain)
• Headache
• Hypoglycemia (when combined with other agents)
• Nasopharyngitis
• Lactic acidosis (rare, metformin-related)

Key clinical trials

• A Double-Blind, Randomized, Active-Comparator (Metformin) Controlled, Clinical Trial to Study the Efficacy and Safety of the Strategy to Start Patients With Type 2 Diabetes Mellitus on Janumet™ Compared to Metformin (PHASE3)

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Metformin + Janufer (Janumet) CI brief — competitive landscape report
• Metformin + Janufer (Janumet) updates RSS · CI watch RSS
• Meir Medical Center portfolio CI