From the Guidelines
Yes, metformin and Januvia (sitagliptin) can be taken together, and this combination is actually quite common in diabetes treatment. These medications work in different ways to help control blood sugar levels. Metformin primarily reduces glucose production by the liver and improves insulin sensitivity, while Januvia works by increasing incretin hormones that stimulate insulin release and reduce glucagon secretion. The combination can provide better glucose control than either medication alone when a single agent isn't sufficient. In fact, there's even a combination pill called Janumet that contains both medications for convenience.
Key Considerations
- Typical dosing ranges from 500-2000mg daily for metformin (often divided) and 100mg once daily for Januvia, though your doctor will prescribe the appropriate doses based on your specific needs.
- It's essential to take these medications as prescribed and monitor for side effects, which may include gastrointestinal issues with metformin and, rarely, joint pain or allergic reactions with Januvia.
- Regular blood sugar monitoring and HbA1c testing will help determine if this combination is effectively managing your diabetes, as recommended by the standards of care in diabetes-2023 1.
Combination Therapy
The use of combination therapy, including metformin and a DPP-4 inhibitor like Januvia, is supported by recent guidelines, which suggest that initial combination therapy can be beneficial for more rapid attainment of glycemic goals and later combination therapy for longer-term management 1. The choice of medication added to metformin should be based on the clinical characteristics of the patient and their preferences, including the presence of established ASCVD or indicators of high ASCVD risk, other comorbidities, and risk for specific adverse drug effects, as well as safety, tolerability, and cost 1.
From the FDA Drug Label
SITAGLIPTIN/METFORMIN 50/850MG
- Combination therapy: The presence of this combination in the drug label suggests that sitagliptin (Januvia) and metformin can be taken together.
- Dosage form: The fact that there is a specific dosage form that combines both medications implies that they are compatible for concurrent use. The FDA drug label indicates that metformin and Januvia (sitagliptin) can be taken together, as evidenced by the availability of a combination product 2.
From the Research
Combination Therapy with Metformin and Januvia
- Metformin and Januvia (sitagliptin) can be taken together, as they have been shown to be safe and effective in improving glycemic control in patients with type 2 diabetes 3, 4, 5.
- The combination of metformin and sitagliptin has been approved by the FDA for use in patients who are not adequately controlled by taking either medication alone or for patients who are already taking both simultaneously 3.
- Studies have demonstrated that the combination of metformin and sitagliptin is well-tolerated, with the most common side effects being gastrointestinal complaints, such as abdominal pain, nausea, and diarrhea 4, 6.
Efficacy of Combination Therapy
- The combination of metformin and sitagliptin has been shown to be effective in improving glycemic control, with a significant reduction in glycated hemoglobin levels compared to placebo or monotherapy with either medication alone 4, 6.
- A clinical trial in Chinese patients with type 2 diabetes found that initial combination therapy with sitagliptin and metformin was generally well-tolerated and provided improvement in glycemic control, with a mean reduction in glycated hemoglobin of 1.67% to 1.83% compared to placebo 6.
Safety Considerations
- The combination of metformin and sitagliptin has been associated with a higher incidence of gastrointestinal adverse events, such as abdominal pain, nausea, and diarrhea, compared to monotherapy with either medication alone 4, 6.
- However, the incidence of hypoglycemia was low and similar across all treatment groups, including the combination therapy group 6.