Sitagliptin

Dipeptidyl peptidase-4 (DPP-4) inhibitor

ATC code: A10BH01

Updated 26 May 2026 · Methodology

Indications

Type 2 diabetes mellitus

Second line

Second-line in type 2 diabetes per / 2024 and SED 2023. First-line is metformin combined with GLP-1 agonists and/or SGLT2 inhibitors when cardiovascular or renal disease is present. Sitagliptin is considered as add-on to metformin in patients without major cardiovascular risk and without obesity, where tolerability and low hypoglycemia risk are priorities. In TECOS, it did not raise heart failure hospitalization risk in T2D patients with cardiovascular disease (unlike saxagliptin).

Sources

ICD-10: E11 · ICD-11: 5A11

Marketing claims without evidence base

The drug is promoted for these uses outside international guidelines. Each entry below is analyzed against AEMPS, FDA, EMA, Cochrane and major RCTs.

Weight loss

Not recommended

Sitagliptin is a dipeptidyl peptidase-4 (DPP-4) inhibitor antidiabetic. It is prescribed for type 2 diabetes ( 2024, 2024). In people without diabetes, sitagliptin is not indicated for weight loss: the drug has a neutral effect on weight and is not approved for obesity treatment. The drug has specific risks: pancreatitis (rare but dangerous), arthralgia, and upper respiratory infections. If sitagliptin was prescribed for weight loss without diabetes, consider seeking a second opinion.

Sources

How to read tiers A–F

AStrong evidence – first or second line in international guidelines
BRecommended in selected cases
CStudy data contradict each other
DBenefit not proven, no documented harm
FDocumented harm, or risk without benefit

Mechanism of action

Selectively inhibits the DPP-4 enzyme that degrades the incretins GLP-1 and GIP. Higher active incretin levels enhance glucose-dependent insulin secretion by β-cells and reduce glucagon. Glycemic effect is moderate ( reduction 0.5–0.8%), but hypoglycemia risk is minimal – without food, incretins do not trigger insulin secretion. Weight-neutral.

Safety

Contraindications

Sitagliptin hypersensitivity
Type 1 diabetes
Diabetic ketoacidosis
Severe hepatic impairment (use with caution)

Serious adverse effects

Acute pancreatitis
Severe allergic reactions, angioedema, Stevens–Johnson syndrome
Bullous pemphigoid
Severe arthralgia (FDA-described, 2015)
Acute kidney injury

Common adverse effects

Nasopharyngitis
Headache
Abdominal pain
Constipation
Hypoglycemia with sulfonylureas

Pregnancy: can you take Sitagliptin?

Limited pregnancy data. Insulin is the foundation in pregnant T2D patients; oral antidiabetics are usually discontinued.

Breastfeeding: can you take Sitagliptin?

No data on milk excretion. Use during lactation is not recommended.

Calculate RID Full profile on NIH LactMed ↗

Reference information, not a clinical decision. Discuss feeding pauses or changes with your physician or an IBCLC.

Practical notes

Timing and administration

Take 100 mg once daily, with or without food. In CKD, adjust: 50 mg at eGFR 30–45 and 25 mg at eGFR under 30. Do not combine with GLP-1 agonists – both potentiate incretin signaling without added benefit. With sulfonylureas, watch for hypoglycemia risk; the sulfonylurea dose usually needs reduction.

Label mentions15 mentions

Verbatim lines from the interaction sections, in the language of the label

From this drug’s label

Majorinsulinclass named in the label
«DRUG INTERACTIONS: Insulin Secretagogues or Insulin Coadministration of sitagliptin tablets with an insulin secretagogue (e.g., sulfonylurea) or insulin may require lower doses of the insulin…»
FDA, section 7 · Open on DailyMed
Majorsulfonylureasclass named in the label
«DRUG INTERACTIONS: Insulin Secretagogues or Insulin Coadministration of sitagliptin tablets with an insulin secretagogue (e.g., sulfonylurea) or insulin may require lower doses of the insulin…»
FDA, section 7 · Open on DailyMed
MinorDigoxin
«Digoxina: Sitagliptina tuvo un efecto pequeño sobre las concentraciones plasmáticas de digoxina. Después de la administración concomitante de 0,25 mg de digoxina con 100 mg de sitagliptina al día…»
AEMPS, section 4.5 · Open on CIMA
anticonceptivos hormonalesclass named in the label
«Los datos in vitro sugieren que sitagliptina ni inhibe ni induce las isoenzimas del CYP450. En los ensayos clínicos, sitagliptina no alteró significativamente la farmacocinética de metformina…»
AEMPS, section 4.5 · Open on CIMA
Ciclosporin
«Ciclosporina: Se llevó a cabo un ensayo para evaluar el efecto de la ciclosporina, un potente inhibidor de la glucoproteína p, sobre la farmacocinética de sitagliptina. La coadministración de una…»
AEMPS, section 4.5 · Open on CIMA
Clarithromycin
«Los ensayos in vitro indicaron que la principal enzima responsable del limitado metabolismo de sitagliptina es la CYP3A4, con contribución de la CYP2C8. En pacientes con función renal normal, el…»
AEMPS, section 4.5 · Open on CIMA
inhibidores del CYP3A4class named in the label
«Los ensayos in vitro indicaron que la principal enzima responsable del limitado metabolismo de sitagliptina es la CYP3A4, con contribución de la CYP2C8. En pacientes con función renal normal, el…»
AEMPS, section 4.5 · Open on CIMA
Itraconazole
«Los ensayos in vitro indicaron que la principal enzima responsable del limitado metabolismo de sitagliptina es la CYP3A4, con contribución de la CYP2C8. En pacientes con función renal normal, el…»
AEMPS, section 4.5 · Open on CIMA
Ketoconazole
«Los ensayos in vitro indicaron que la principal enzima responsable del limitado metabolismo de sitagliptina es la CYP3A4, con contribución de la CYP2C8. En pacientes con función renal normal, el…»
AEMPS, section 4.5 · Open on CIMA
Metformin
«Metformina: La coadministración de dosis repetidas de 1.000 mg de metformina dos veces al día con 50 mg de sitagliptina no alteró significativamente la farmacocinética de sitagliptina en pacientes…»
AEMPS, section 4.5 · Open on CIMA
Ritonavir
«Los ensayos in vitro indicaron que la principal enzima responsable del limitado metabolismo de sitagliptina es la CYP3A4, con contribución de la CYP2C8. En pacientes con función renal normal, el…»
AEMPS, section 4.5 · Open on CIMA
Simvastatin
«Los datos in vitro sugieren que sitagliptina ni inhibe ni induce las isoenzimas del CYP450. En los ensayos clínicos, sitagliptina no alteró significativamente la farmacocinética de metformina…»
AEMPS, section 4.5 · Open on CIMA
Warfarin
«Los datos in vitro sugieren que sitagliptina ni inhibe ni induce las isoenzimas del CYP450. En los ensayos clínicos, sitagliptina no alteró significativamente la farmacocinética de metformina…»
AEMPS, section 4.5 · Open on CIMA

From other drugs’ labels

Dapagliflozin
«En los estudios de interacción realizados en sujetos sanos, usando principalmente un diseño de dosis única, sugieren que la farmacocinética de dapagliflozina no se ve alterada por la metformina…»
AEMPS, section 4.5 · Open on CIMA
Empagliflozin
«Los estudios de interacciones sugieren que la farmacocinética de empagliflozina no se vio influida por la administración conjunta de metformina, glimepirida, pioglitazona, sitagliptina, linagliptina…»
AEMPS, section 4.5 · Open on CIMA

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Frequently asked

What is Sitagliptin used for?

Sitagliptin is evaluated for the following indications with varying evidence strength: Type 2 diabetes mellitus (evidence tier B), Weight loss (evidence tier F). See the full indication matrix with dosing and citations above on this page.

What are the side effects of Sitagliptin?

Common side effects of Sitagliptin (≥ 1 in 100): Nasopharyngitis, Headache, Abdominal pain, Constipation, Hypoglycemia with sulfonylureas. See the Safety section for uncommon and serious reactions.

Is Sitagliptin safe during pregnancy?

Limited pregnancy data. Insulin is the foundation in pregnant T2D patients; oral antidiabetics are usually discontinued.

Is Sitagliptin compatible with breastfeeding?

No data on milk excretion. Use during lactation is not recommended.

Who should not take Sitagliptin?

Sitagliptin is contraindicated in: Sitagliptin hypersensitivity; Type 1 diabetes; Diabetic ketoacidosis; Severe hepatic impairment (use with caution). Full list in the Safety section.

Official sources

Direct links to regulator labels. Open in a new tab.

AEMPS / CIMA
EMALabel dated 03/21/2007
FDA / DailyMedLabel dated 08/12/2026

Other drugs in this group

Sitagliptin + Metformin, Tirzepatide, Vildagliptin, Vildagliptin + Metformin, Glimepiride, Insulin glargine, Liraglutide, Dapagliflozin