Adults with Normal Renal Function (GFR 90 mL/min): Reduction in the risk or delay of the onset of type 2 diabetes: Metformin should only be considered where intensive lifestyle modifications for 3 to 6 months have not resulted in adequate glycaemic control.
The therapy should be initiated with one tablet Glucophage XR 500 mg once daily with the evening meal.
After 10 to 15 days dose adjustment on the basis of blood glucose measurements is recommended (OGTT and/or FPG and/or HbA1C values to be within the normal range). A slow increase of dose may improve gastro-intestinal tolerability. The maximum recommended dose is 4 tablets (2000 mg) once daily with the evening meal.
It is recommended to regularly monitor (every 3-6 months) the glycaemic status (OGTT and/or FPG and/or HbA1c value) as well as the risk factors to evaluate whether treatment needs to be continued, modified or discontinued.
A decision to re-evaluate therapy is also required if the patient subsequently implements improvements to diet and/or exercise, or if changes to the medical condition will allow increased lifestyle interventions to be possible.
Monotherapy of Glucophage XR 500 mg, 750 and 1000 mg: The usual starting dose is one tablet of Glucophage XR 500 mg once daily.
After 10 to 15 days the dose should be adjusted on the basis of blood glucose measurements. A slow increase of dose may improve gastro-intestinal tolerability. The maximum recommended dose is 2000 mg XR once daily with the evening meal.
Dosage increases should be made in increments of 500 mg every 10-15 days, up to a maximum of 2000 mg once daily with the evening meal. If glycaemic control is not achieved on 2000 mg once daily, Glucophage XR 1000 mg twice daily should be considered, with both doses being given with food. If glycaemic control is still not achieved, patients may be switched to Metformin tablets IR tablets to a maximum dose of 3000 mg daily.
Glucophage XR 750 mg and 1000 mg is intended for patients who are already treated with Metformin tablets (prolonged or immediate release). The dose of Glucophage XR 750 mg or 1000 mg should be equivalent to the daily dose of Metformin tablets (prolonged or immediate release), up to a maximum dose of 1500 mg or 2000 mg respectively, given with the evening meal.
In patients already treated with Metformin tablets, the starting dose of Glucophage XR should be equivalent to the daily dose of Metformin IR tablets. In patients treated with Metformin at a dose above 2000 mg daily, switching to Glucophage XR is not recommended.
If transfer from another oral antidiabetic agent is intended: discontinue the other agent and initiate Glucophage XR at the dose indicated as previously mentioned.
Combination with Insulin: Metformin hydrochloride and Insulin may be used in combination therapy to achieve better blood glucose control. The usual starting dose of Glucophage XR is 500 mg once daily with the evening meal, while Insulin dosage is adjusted on the basis of blood glucose measurements. After titration, switch to Glucophage XR 1000 mg should be considered.
Elderly: Due to the potential for decreased renal function in elderly subjects, the Metformin dosage should be adjusted based on renal function. Regular assessment of renal function is necessary (see Precautions).
Benefit in the reduction of risk or delay of the onset of type 2 diabetes mellitus has not been established in patients 75 years and older and Metformin initiation is therefore not recommended in these patients.
Patients with Renal Impairment: Metformin may be used in patients with moderate renal impairment (creatinine clearance or glomerular filtration rate (GFR) between 30 and 59 mL/min) only in the absence of other conditions that may increase the risk of lactic acidosis and with the following dose adjustments: Patients with creatinine clearance or a GFR between 45 and 59 mL/min: the starting dose is 500 mg or 750 mg Metformin hydrochloride, once daily. The maximum dose is 1000 mg daily. The renal function should be closely monitored (every 3 - 6 months).
Patients with creatinine clearance or a GFR between 30 and 44 mL/min: it is not recommended to initiate Metformin hydrochloride, but Metformin can be maintained in patients already treated, provided that the maximum daily dose is not higher than 1000 mg. The renal function should be closely monitored every 3 months.
If creatinine clearance or GFR fall below 30 mL/min, Metformin must be discontinued immediately.
Children: In the absence of available data, Glucophage XR should not be used in children.