Prescription medicine
Metformin and sitagliptin Brand names: Zituvimet, Janumet
Metformin and sitagliptin (Janumet) is a prescription medicine with an FDA approval on record since 2007. FDA's NDC Directory lists it from 4 generic labelers, and pharmacies paid $1.76 per sitagliptin phosphate-metformin 50 mg-1,000 mg tablet in the October 7, 2026 NADAC survey; its other strengths are brand-only, $5.28 per Janumet XR 50-1,000 mg tablet.
- Generic listed
- Boxed warning
Check it at the source: the metformin and sitagliptin FDA label on DailyMed (effective August 11, 2026, Merck Sharp & Dohme LLC); the NDA 22044 record on Drugs@FDA; every metformin and sitagliptin label on DailyMed.
Highlights of the record
FDA label of August 11, 2026; NDC Directory, Drugs@FDA and Orange Book, October 8, 2026; NADAC October 7, 2026
LACTIC ACIDOSIS.
Postmarketing cases of metformin-associated lactic acidosis have resulted in death, hypothermia, hypotension, and resistant bradyarrhythmias. The onset of metformin-associated lactic acidosis is often subtle, accompanied only by nonspecific symptoms such as malaise, myalgias, respiratory distress, somnolence, and abdominal pain. Metformin-associated lactic acidosis was characterized by elevated blood lactate levels (>5 mmol/Liter), anion gap acidosis (without evidence of ketonuria or ketonemia), an increased lactate/pyruvate ratio, and metformin plasma levels generally >5 mcg/mL [see Warnings and Precautions (5.1) ]. Risk factors for metformin-associated lactic acidosis include renal impairment, concomitant use of certain drugs (e.g., carbonic anhydrase inhibitors such as topiramate), age 65 years old or greater, having a radiological study with contrast, surgery and other procedures, hypoxic states (e.g., acute congestive heart failure), excessive alcohol intake, hepatic impairment, and mitochondrial diseases [see Warnings and Precautions (5.1) ]. Steps to reduce the risk of and manage metformin-associated lactic acidosis in these high-risk groups are provided in the full prescribing information [see Dosage and Administration (2.2), Contraindications (4), Warnings and Precautions (5.1), Drug Interactions (7), and Use in Specific Populations (8.6 , 8.7) ]. […]
Used for
From the label: indications and usageJANUMET ® XR is indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus.
Forms and strengths
- 50 mg / 1000 mg
- 50 mg / 500 mg
- 100 mg / 1000 mg
Film-coated extended-release tablet; film-coated tablet.
On the market
- Earliest approval on file
- March 30, 2007 Janumet, Msd Sub Merck; Drugs@FDA’s file, where older or withdrawn approvals can be missing
- Generic approvals
- 3 first June 4, 2025; 3 with a marketed status in Drugs@FDA
- Labelers listed (NDC)
- 9 of which 4 under generic applications, 5 under brand applications, repackagers included
- Last listed patent
- January 21, 2029 Janumet tablets; not a generic launch date
Supply and safety
- Pharmacy cost (NADAC)
- $1.76 per tablet Sitagliptin phosphate-metformin 50 mg-1,000 mg tablet
- Shortage (FDA)
- No current entry
- Recalls by its makers (FDA)
- 1 since 2022 0 Class I among all firms' recalls; latest March 31, 2022
- FAERS reports
- 21,442 through July 30, 2026
What is metformin and sitagliptin used for?
From the label: indications and usageJANUMET ® XR is indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus. JANUMET XR is a combination of sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, and metformin hydrochloride (HCl), a biguanide indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus. ( 1 ) Limitations of Use: Not for the treatment of type 1 diabetes. ( 1 ) Has not been studied in patients with a history of pancreatitis. ( 1 , 5.2 ) Limitations of Use JANUMET XR should not be used in patients with type 1 diabetes mellitus. JANUMET XR has not been studied in patients with a history of pancreatitis. […]
Conditions named in the indications of metformin and sitagliptin's FDA labels, with every medicine labeled for each:
FDA pharmacologic class: Biguanide and Dipeptidyl Peptidase 4 Inhibitor.
Source: FDA drug label (JANUMET XR), Merck Sharp & Dohme LLC, effective August 11, 2026 (SPL set 64beb3d2-3aeb-4cd5-ba11-dacf6c9a5b50), via openFDA; the full label on DailyMed
What does the patient leaflet for metformin and sitagliptin say first?
The FDA-approved Medication Guide or Patient Information that comes with the medicine, in its own words.
From the patient leaflet: What is the most important information I should know about JANUMET XR?JANUMET XR can cause serious side effects, including: 1. Lactic Acidosis. Metformin, one of the medicines in JANUMET XR, can cause a rare but serious condition called lactic acidosis (a buildup of an acid in the blood) that can cause death. Lactic acidosis is a medical emergency and must be treated in the hospital. Stop taking JANUMET XR and call your doctor right away if you have any of the following symptoms, which could be signs of lactic acidosis: you feel cold in your hands or feet you feel dizzy or lightheaded you have a slow or irregular heartbeat you feel very weak or tired you have unusual (not normal) muscle pain you have trouble breathing you feel sleepy or drowsy you have stomach pains, nausea or vomiting Most people who have had lactic acidosis with metformin have other things that, combined with the metformin, led to the lactic acidosis. Tell your doctor if you have any of the following, because you have a higher chance for getting lactic acidosis with JANUMET XR if you: have severe kidney problems or your kidneys are affected by certain x-ray tests that use injectable dye have liver problems drink alcohol very often, or drink a lot of alcohol in short-term "binge" drinking get dehydrated (lose a large amount of body fluids). This can happen if you are sick with a fever, vomiting, or diarrhea. […]
From the patient leaflet: How should I store JANUMET XR?Store JANUMET XR at room temperature, between 68°F to 77°F (20°C to 25°C). Store in a dry place and keep the cap tightly closed. Keep JANUMET XR and all medicines out of the reach of children.
Source: FDA drug label (JANUMET XR), Merck Sharp & Dohme LLC, effective August 11, 2026 (SPL set 64beb3d2-3aeb-4cd5-ba11-dacf6c9a5b50), via openFDA; the full label on DailyMed
Is there a generic for metformin and sitagliptin (Janumet)?
The FDA approved the first generic metformin and sitagliptin on June 4, 2025. 3 generic applications are approved; 3 of them carry a current (not discontinued) marketing status in Drugs@FDA; that status is not evidence that the generic is on sale. Drugs@FDA also holds 4 tentative approvals: the FDA found the generic approvable, but patents or exclusivity keep it from final approval for now.
FDA's NDC Directory lists metformin and sitagliptin from 4 labelers under a generic (ANDA) application and from 5 brand labelers. A listing means the company has registered the product for sale; it does not show that every pharmacy stocks it.
The Orange Book lists 2 patents for Janumet tablets: the compound patent runs to November 24, 2026 (pediatric exclusivity to May 24, 2027), and the last listed entry to January 21, 2029. A patent or exclusivity date is not the date a generic goes on sale: court cases and settlements move it either way.
- 2007 earliest approval on file
- 2025 first generic approved
- 2029 last listed patent
- red ticks recalls
Source: Drugs@FDA, FDA NDC Directory and the Orange Book (openFDA bulk files, October 8, 2026)
What do pharmacies pay for metformin and sitagliptin (Janumet)?
In CMS's NADAC survey of October 7, 2026, pharmacies paid $1.76 per Sitagliptin phosphate-metformin 50 mg-1,000 mg tablet. The chart's scale runs from the lowest to the highest price shown, not from zero. NADAC is what retail pharmacies paid their wholesalers, per unit, in CMS's monthly survey; what a patient pays depends on insurance and the pharmacy.
- Sitagliptin phosphate-metformin 50 mg-1,000 mg tablet (generic)
- Janumet XR 50-1,000 mg tablet (brand)
| Strength and form | Brand or generic | Pharmacy cost | 30 tablets, or one pen or vial | 12-month change |
|---|---|---|---|---|
| Sitagliptin phosphate-metformin 50 mg-1,000 mg tablet | Generic | $1.76 per tablet | $52.80 | n/a |
| Sitagliptin phosphate-metformin 50 mg-500 mg tablet | Generic | $1.92 per tablet | $57.64 | n/a |
| Janumet 50-1,000 mg tablet | Brand | $5.28 per tablet | $158.38 | no change |
| Janumet 50-500 mg tablet | Brand | $5.28 per tablet | $158.52 | no change |
| Janumet XR 100-1,000 mg tablet | Brand | $10.56 per tablet | $316.68 | no change |
| Janumet XR 50-1,000 mg tablet | Brand | $5.28 per tablet | $158.34 | no change |
| Janumet XR 50-500 mg tablet | Brand | $5.28 per tablet | $158.49 | no change |
| Zituvimet 50-1,000 mg tablet | Brand | $5.03 per tablet | $150.92 | -0.1% |
| Zituvimet 50-500 mg tablet | Brand | $5.06 per tablet | $151.75 | +0.2% |
| Zituvimet XR 100-1,000 mg tablet | Brand | $10.08 per tablet | $302.37 | +0.3% |
| Zituvimet XR 50-1,000 mg tablet | Brand | $5.02 per tablet | $150.58 | -0.4% |
| Zituvimet XR 50-500 mg tablet | Brand | $5.01 per tablet | $150.29 | n/a |
Source: CMS National Average Drug Acquisition Cost (NADAC) survey, October 7, 2026: what retail pharmacies paid per unit; not a counter price
Has metformin and sitagliptin been recalled?
The FDA's Enforcement Report lists 1 recall naming metformin and sitagliptin since 2022: 0 Class I (the most serious), 1 Class II, 0 Class III; 0 still ongoing. A recall names products and lots, not every product of the medicine.
| Started | Class | Company | Reason |
|---|---|---|---|
| March 31, 2022 | Class II | MERCK SHARP & DOHME CORP | Presence of foreign substance: Presence of stainless steel particulates in tablets. |
Source: FDA Enforcement Report (drug recalls) via openFDA, through October 8, 2026
What does the metformin and sitagliptin label say about other medicines?
The metformin and sitagliptin label names 10 other medicines in its interaction, contraindication or warning sections. The sentences are the labels' own; a label lists what its studies and reports found, not every interaction.
| Medicine named | Section | What the label says |
|---|---|---|
| Acetazolamide | drug interactions | Carbonic Anhydrase Inhibitors Clinical Impact: Carbonic anhydrase inhibitors frequently cause a decrease in serum bicarbonate and induce non-anion gap, hyperchloremic metabolic acidosis. Concomitant use of these drugs with JANUMET XR may increase the risk for lactic acidosis. Intervention: Consider more frequent monitoring of these patients. Examples: Topiramate, zonisamide, acetazolamide or dichlorphenamide. |
| Cimetidine | drug interactions | Drugs that Reduce Metformin Clearance Clinical Impact: Concomitant use of drugs that interfere with common renal tubular transport systems involved in the renal elimination of metformin (…) could increase systemic exposure to metformin and may increase the risk for lactic acidosis. Intervention: Consider the benefits and risks of concomitant use with JANUMET XR. Examples: Ranolazine, vandetanib, dolutegravir, and cimetidine. |
| Dichlorphenamide | drug interactions | Carbonic Anhydrase Inhibitors Clinical Impact: Carbonic anhydrase inhibitors frequently cause a decrease in serum bicarbonate and induce non-anion gap, hyperchloremic metabolic acidosis. Concomitant use of these drugs with JANUMET XR may increase the risk for lactic acidosis. Intervention: Consider more frequent monitoring of these patients. Examples: Topiramate, zonisamide, acetazolamide or dichlorphenamide. |
| Dolutegravir | drug interactions | Drugs that Reduce Metformin Clearance Clinical Impact: Concomitant use of drugs that interfere with common renal tubular transport systems involved in the renal elimination of metformin (…) could increase systemic exposure to metformin and may increase the risk for lactic acidosis. Intervention: Consider the benefits and risks of concomitant use with JANUMET XR. Examples: Ranolazine, vandetanib, dolutegravir, and cimetidine. |
| Isoniazid | drug interactions | Clinical Impact: Certain drugs tend to produce hyperglycemia and may lead to loss of glycemic control. … phenytoin, nicotinic acid, sympathomimetics, calcium channel blockers, and isoniazid. |
| Phenytoin | drug interactions | Clinical Impact: Certain drugs tend to produce hyperglycemia and may lead to loss of glycemic control. … corticosteroids, phenothiazines, thyroid products, estrogens, oral contraceptives, phenytoin, nicotinic acid, sympathomimetics, calcium channel blockers, and isoniazid. |
| Ranolazine | drug interactions | Drugs that Reduce Metformin Clearance Clinical Impact: Concomitant use of drugs that interfere with common renal tubular transport systems involved in the renal elimination of metformin (…) could increase systemic exposure to metformin and may increase the risk for lactic acidosis. Intervention: Consider the benefits and risks of concomitant use with JANUMET XR. Examples: Ranolazine, vandetanib, dolutegravir, and cimetidine. |
| Topiramate | boxed warning | Risk factors for metformin-associated lactic acidosis include renal impairment, concomitant use of certain drugs (e.g., carbonic anhydrase inhibitors such as topiramate), age 65 years old or greater, having a radiological study with contrast, surgery and other procedures, hypoxic states (e.g., acute congestive heart … |
| Vandetanib | drug interactions | Drugs that Reduce Metformin Clearance Clinical Impact: Concomitant use of drugs that interfere with common renal tubular transport systems involved in the renal elimination of metformin (…) could increase systemic exposure to metformin and may increase the risk for lactic acidosis. Intervention: Consider the benefits and risks of concomitant use with JANUMET XR. Examples: Ranolazine, vandetanib, dolutegravir, and cimetidine. |
| Zonisamide | drug interactions | Carbonic Anhydrase Inhibitors Clinical Impact: Carbonic anhydrase inhibitors frequently cause a decrease in serum bicarbonate and induce non-anion gap, hyperchloremic metabolic acidosis. Concomitant use of these drugs with JANUMET XR may increase the risk for lactic acidosis. Intervention: Consider more frequent monitoring of these patients. Examples: Topiramate, zonisamide, acetazolamide or dichlorphenamide. |
Source: FDA drug label (JANUMET XR), Merck Sharp & Dohme LLC, effective August 11, 2026 (SPL set 64beb3d2-3aeb-4cd5-ba11-dacf6c9a5b50), via openFDA; the full label on DailyMed
What do FAERS reports show for metformin and sitagliptin?
The FDA Adverse Event Reporting System holds 21,442 reports that list metformin and sitagliptin among the medicines taken, through July 30, 2026, each a report of something that happened, not proof the medicine caused it; 2,107 are coded as a death and 6,972 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is.
Reports received each year
The most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026
What else is labeled for the same conditions as metformin and sitagliptin?
19 other medicines are given the same way (oral) and in the same FDA class as metformin and sitagliptin or labeled mainly for the same use (type 2 diabetes), the same class first. Type 2 diabetes lists all 52 medicines labeled for it, by any route. The first 8 are below. They are listed as records, not as substitutes: whether one can replace another is a prescriber's decision.
| Medicine | Shared indication | Generic labelers (oral) | Pharmacy cost | Shortage |
|---|---|---|---|---|
| Alogliptin | Type 2 diabetes | none listed | $4.96 per tablet 12.5 mg tablet | No current entry |
| Alogliptin and pioglitazone | Type 2 diabetes | none listed | $4.73 per tablet 25-15 mg tablet | No current entry |
| Saxagliptin | Type 2 diabetes | 3 labelers | $1.04 per tablet 5 mg tablet | No current entry |
| Linagliptin | Type 2 diabetes | none listed | $16.80 per tablet 5 mg tablet | No current entry |
| Empagliflozin and linagliptin | Type 2 diabetes | none listed | $11.24 per tablet 10 mg-5 mg tablet | No current entry |
| Glipizide | Type 2 diabetes | 31 labelers | $0.0339 per tablet 5 mg tablet | No current entry |
| Glimepiride | Type 2 diabetes | 29 labelers | $0.0507 per tablet 4 mg tablet | No current entry |
| Pioglitazone | Type 2 diabetes | 22 labelers | $0.0675 per tablet 15 mg tablet | No current entry |
Every medicine labeled for the same conditions as metformin and sitagliptin
Source: FDA drug labels (indications), NDC Directory, NADAC of October 7, 2026, FDA shortages (October 8, 2026)
What next?
- Alternatives to metformin and sitagliptin
- 19 medicines for the same use
- Other biguanides
- the pharmacologic class, with prices and generics
- Metformin and sitagliptin side effects
- the label's list beside FAERS reports
- Check an interaction
- what two or more labels say about each other