Short answer: The label says side effects in 990 people taking ertugliflozin with sitagliptin for 26 weeks were similar to ertugliflozin alone. In pooled placebo-controlled ertugliflozin trials, the most common were female genital yeast infections (9.1% on 5 mg and 12.2% on 15 mg vs 3.0% on placebo), male genital yeast infections (3.7% and 4.2% vs 0.4%) and urinary tract infections (4.0% and 4.1% vs 3.9%). Steglujan has no boxed warning.
What Steglujan is approved for: Steglujan combines ertugliflozin, an SGLT2 inhibitor, with sitagliptin, a DPP-4 inhibitor. It is approved, along with diet and exercise, to improve blood sugar control in adults with type 2 diabetes (section 1). It is not recommended for type 1 diabetes, and it has not been studied in people who have had pancreatitis.
Source
STEGLUJAN (ertugliflozin and sitagliptin) tablets, for oral use, prescribing information and Medication Guide. Merck Sharp & Dohme. DailyMed, version published June 23, 2026. DailyMed setid c2c553d8-5a9d-4366-bf53-8bdb5a876d19
No. The current Steglujan label has no boxed warning.
These are the label's own numbers from the Adverse Reactions section. Where the label compares with placebo (a dummy treatment), both columns are shown, so you can see how much more often a reaction happened on Steglujan.
| Adverse reaction | Placebo N = 515 | Ertugliflozin 5 mg N = 519 | Ertugliflozin 15 mg N = 510 |
|---|---|---|---|
| Female genital mycotic infections | 3.0% | 9.1% | 12.2% |
| Male genital mycotic infections | 0.4% | 3.7% | 4.2% |
| Urinary tract infections | 3.9% | 4.0% | 4.1% |
| Headache | 2.3% | 3.5% | 2.9% |
| Vaginal pruritus | 0.4% | 2.8% | 2.4% |
| Increased urination | 1.0% | 2.7% | 2.4% |
| Nasopharyngitis | 2.3% | 2.5% | 2.0% |
| Back pain | 2.3% | 1.7% | 2.5% |
| Weight decreased | 1.0% | 1.2% | 2.4% |
| Thirst | 0.6% | 2.7% | 1.4% |
Number (%) of patients in a pool of three 26-week placebo-controlled trials: one of ertugliflozin alone and two added to metformin or to metformin and sitagliptin. Female and male rates use the number of women or men in each group. Nasopharyngitis means a stuffy or runny nose with sore throat.
| Study (26 weeks) and measure | Placebo | Ertugliflozin 5 mg arm | Ertugliflozin 15 mg arm |
|---|---|---|---|
| Factorial study, with sitagliptin on metformin (N = 243 / 244): Overall [N (%)] | No placebo arm | 13 (5.3) | 22 (9.0) |
| Factorial study: Severe [N (%)] | No placebo arm | 0 (0.0) | 1 (0.4) |
| Add-on to metformin and sitagliptin (N = 153 / 156 / 153): Overall [N (%)] | 5 (3.3) | 7 (4.5) | 3 (2.0) |
| Add-on to metformin and sitagliptin: Severe [N (%)] | 1 (0.7) | 1 (0.6) | 0 (0.0) |
| Initial therapy with sitagliptin (N = 97 / 98 / 96): Overall [N (%)] | 1 (1.0) | 6 (6.1) | 3 (3.1) |
| Initial therapy with sitagliptin: Severe [N (%)] | 0 (0.0) | 0 (0.0) | 2 (2.1) |
Overall means a glucose of 70 mg/dL or less; severe means needing help, losing consciousness or having a seizure, whatever the glucose. The factorial study had no placebo arm.
In people with moderate kidney impairment, fluid-loss side effects such as dehydration, dizziness on standing, fainting and low blood pressure were 0% on placebo, 4.4% on ertugliflozin 5 mg and 1.9% on 15 mg.
In the VERTIS CV heart outcome trial, lower limb amputations were 4.7, 5.7 and 6.0 events per 1,000 patient-years on placebo, ertugliflozin 5 mg and 15 mg; urinary tract infections were 10.2%, 12.2% and 12.0%.
Phimosis (tight foreskin) was reported in 8 of 1,729 men (0.5%) on ertugliflozin, four of whom needed circumcision.
Sitagliptin: low blood sugar was 12.2% vs 1.8% on placebo when added to glimepiride, and 15.5% vs 7.8% when added to insulin. Acute pancreatitis was 0.1 per 100 patient-years in both the sitagliptin and control groups across 19 trials.
Ertugliflozin raised LDL cholesterol by 2.6% on 5 mg and 5.4% on 15 mg relative to placebo at week 26.
Reported after approval, with frequency unknown: Fournier's gangrene; angioedema and rash; allergic reactions including anaphylaxis, hives, skin vasculitis, bullous pemphigoid and Stevens-Johnson syndrome; liver enzyme rises; acute pancreatitis including fatal cases; constipation; vomiting; mouth ulcers; worsening kidney function including acute kidney failure; severe joint pain; muscle pain; and rhabdomyolysis.
The Warnings and Precautions part of the label lists these. Each line gives the label's heading and what it means in plain words.
Diabetic ketoacidosis in type 1 diabetes and other ketoacidosis. Ketoacidosis, which can be fatal, can happen even with blood sugar below 250 mg/dL, and has been reported in type 2 diabetes. Sugar keeps showing in the urine for 4 days after stopping. Steglujan is stopped if ketoacidosis is suspected, and it is not for type 1 diabetes.
Pancreatitis. Acute pancreatitis, including fatal hemorrhagic or necrotizing pancreatitis, has been reported with sitagliptin. Steglujan is stopped promptly if it is suspected.
Lower limb amputation. In a heart outcome trial, amputations were more frequent on ertugliflozin, mostly of the toe and foot. People are watched for infections, new pain, sores or ulcers of the legs and feet.
Acute renal failure. Worsening kidney function, including acute kidney failure sometimes needing dialysis, has been reported with sitagliptin.
Volume depletion. Steglujan can cause fluid loss, low blood pressure and acute kidney injury, especially with kidney problems, in older people, with low blood pressure or with loop diuretics. Fluid status and kidney function are checked before starting.
Genitourinary infections, including Fournier's gangrene. Serious urinary infections, kidney infections, genital yeast infections and a rare, life-threatening genital-area infection (Fournier's gangrene) have been reported. Pain, redness or swelling in the genital area with fever is checked right away.
Heart failure. Heart failure was linked to two other DPP-4 inhibitors. Risks and benefits are weighed in people at risk, and they are watched for symptoms.
Low blood sugar with insulin or a sulfonylurea. Ertugliflozin may raise the risk of low blood sugar with insulin or a medicine that makes the body release insulin, and a lower dose of those may lower the risk.
Hypersensitivity reactions. Serious allergic reactions to sitagliptin, including anaphylaxis, angioedema and Stevens-Johnson syndrome, have been reported within the first 3 months, some after the first dose. Steglujan is stopped if one is suspected.
Severe and disabling joint pain. Severe joint pain has been reported with DPP-4 inhibitors, starting from one day to years after starting, and easing after stopping.
Bullous pemphigoid. A blistering skin condition needing hospital care has been reported with DPP-4 inhibitors. Steglujan is stopped if it is suspected.
From the Medication Guide that comes with Steglujan:
Dose Track has a side-effect log. Each entry records the symptom, a severity (none, mild, moderate, severe or life-threatening), the date and an optional note, and can be tied to a specific dose or logged on its own. The history screen shows what you logged over time, which makes it easier to tell your prescriber when a reaction started and whether it is easing. The app records what you enter; it does not judge whether a symptom is serious. For anything on the label's call-your-doctor list, call your doctor.
This page is what the FDA label says, in plain words. It is not medical advice. Follow your prescriber, and ask them or your pharmacist about anything here.