Consumer medicine information

1. Why am I being treated with METFORMIN SANDOZ XR?

METFORMIN SANDOZ XR contains the active ingredients metformin (as hydrochloride). METFORMIN SANDOZ XR is used to lower blood sugar levels in adults with type 2 diabetes mellitus.
For more information, see Section 1. Why am I being treated with METFORMIN SANDOZ XR? in the full CMI.

2. What should I know before treatment with METFORMIN SANDOZ XR?

Do not use if you have ever had an allergic reaction to METFORMIN SANDOZ XR or any of the ingredients listed at the end of the CMI.
Talk to your doctor if you have any other medical conditions, take any other medicines, or are pregnant or plan to become pregnant or are breastfeeding.
For more information, see Section 2. What should I know before treatment with METFORMIN SANDOZ XR? in the full CMI.

3. What if I am taking other medicines?

Some medicines may interfere with METFORMIN SANDOZ XR and affect how it works.
A list of these medicines is in Section 3. What if I am taking other medicines? in the full CMI.

4. How is METFORMIN SANDOZ XR given?

Take your METFORMIN SANDOZ XR tablets once a day with a meal.
More instructions can be found in Section 4. How is METFORMIN SANDOZ XR given? in the full CMI.

5. What should I know during treatment with METFORMIN SANDOZ XR?

6. Are there any side effects?

Common side effects include: nausea, vomiting, diarrhoea, stomach pain, taste disturbance and loss of appetite.
Serious side effects that need to be noted are: lactic acidosis; trouble breathing; feeling weak, tired or generally unwell; unusual muscle pain; sleepiness; dizziness or lightheadedness; shivering, feeling extremely cold; slow heartbeat.
For more information, including what to do if you have any side effects, see Section 6. Are there any side effects? in the full CMI.

Boxed Warnings

Life threatening lactic acidosis can occur due to accumulation of metformin. The main risk factor is renal impairment, other risk factors include old age associated with reduced renal function.

1 Name of Medicine

Metformin hydrochloride.

2 Qualitative and Quantitative Composition

Metformin Sandoz XR available in two strengths: 500 mg and 1000 mg.
Each Metformin Sandoz XR 500 extended release tablets contain 500 mg of metformin hydrochloride.
Each Metformin Sandoz XR 1000 extended release tablets contain 1000 mg of metformin hydrochloride.
For the full list of excipients, see Section 6.1 List of Excipients.

3 Pharmaceutical Form

Extended release tablets.
Metformin Sandoz XR 500 mg extended release tablets. White to off-white coloured, capsule shaped, biconvex tablet, debossed with "500" on one side and plain on the other side.
Metformin Sandoz XR 1000 extended release tablets. White to off-white coloured, oval shaped biconvex tablets debossed with '1000' on one side and plain on other side.
Metformin Sandoz XR tablets are gluten free.

4 Clinical Particulars

4.9 Overdose

Symptoms. Although hypoglycaemia has not been seen with ingestion of up to 85 g of metformin alone, lactic acidosis has occurred in such circumstances. This condition is a medical emergency and must be treated in hospital. The onset of lactic acidosis is often subtle and accompanied only by non-specific symptoms such as malaise, myalgia, respiratory distress, increasing somnolence and non-specific abdominal distress. There may also be associated hypothermia, hypotension and resistant bradyarrhythmias with more marked acidosis. Lactic acidosis should be suspected in any diabetic patient with metabolic acidosis lacking evidence of ketoacidosis (ketonuria and ketonaemia).
Treatment. Lactic acidosis may develop in diabetic metformin-treated patients with overdose. Lactic acidosis is diagnosed and monitored by measurement of serum electrolytes, arterial pH and pCO₂ and arterial lactate plasma levels.
The aim of treatment is to manage any underlying disorder, and in some cases this will be sufficient to enable the body's homeostatic mechanism to correct the acid-base imbalance. The advantages of more active treatment of the acidosis must be balanced against the risks, including over-alkalinisation with sodium bicarbonate. Because metformin hydrochloride is dialysable (with a clearance of up to 170 mL/min under good haemodynamic conditions), prompt haemodialysis is recommended to correct the acidosis and remove the accumulated metformin.
For information on the management of overdose, contact the Poisons Information Centre on 13 11 26 (Australia).

5 Pharmacological Properties

5.3 Preclinical Safety Data

Genotoxicity. Preclinical data reveal no specific hazard for humans based on conventional studies on safety pharmacology, repeated dose toxicity, genotoxicity, carcinogenic potential or reproductive toxicity.
Carcinogenicity. See Genotoxicity.

6 Pharmaceutical Particulars

6.7 Physicochemical Properties

Metformin hydrochloride are white crystals easily soluble in water, sparingly soluble in alcohol, practically insoluble in acetone and methylene chloride.
Metformin is a strong base with a pKa greater than 12. At pH < 12, which is always the case in the body, metformin is very hydrophilic: the octanol/water partition coefficient is 0.05. The melting point of metformin hydrochloride is 224°C. Metformin hydrochloride is a very stable molecule.
Chemical structure.
https://stagingapi.mims.com/au/public/v2/images/fullchemgif/CSMETFOH.gif Chemical name: 1,1-dimethylbiguanide hydrochloride.
Molecular formula: C₄H₁₂ClN₅.
Molecular weight: 165.63.
CAS number. 1115-70-4.

7 Medicine Schedule (Poisons Standard)

S4 (Prescription Only Medicine).

Summary Table of Changes

https://stagingapi.mims.com/au/public/v2/images/fulltablegif/METSXRST.gif