Like all medicines, Janumet may cause side effects, although not everybody gets them.
Very rarely patients taking metformin (one of the active substances of Janumet) have experienced a serious condition called lactic acidosis (too much lactic acid in your blood). This is more common in people whose kidneys are not working properly. Stop taking Janumet and see a doctor straight away if you notice any of the following symptoms:
- feeling sick (nausea) or being sick (vomiting), abdominal pain, muscular cramps, unexplained weight loss, rapid breathing, and feeling cold or uncomfortable.
Very common side effects (likely to occur in more than 1 per 10 patients).
Common side effects (likely to occur in less than 1 per 10 but more than 1 per 100 patients). Uncommon side effects (likely to occur in less than 1 per 100 but more than 1 per 1,000 patients). Rare side effects (likely to occur in less than 1 per 1,000 but more than 1 per 10,000). Very rare side effects (likely to occur in less than 1 per 10,000).
Some patients taking metformin have experienced the following side effects after starting sitagliptin: Common: nausea
Uncommon: weight loss, loss of appetite, abdominal pain, diarrhoea, low blood sugar, drowsiness
Some patients have experienced stomach discomfort when starting the combination of sitagliptin and metformin together.
Some patients have experienced the following side effects while taking Janumet with a sulphonylurea: Very common: low blood sugar
Some patients have experienced the following side effects while taking Janumet in combination with rosiglitazone:
Common: headache, cough, diarrhoea, vomiting, low blood sugar, fungal skin infection, upper respiratory infection, swelling of the hands or legs.
Some patients have experienced the following side effects while taking Janumet in combination with insulin:
Very common: low blood sugar
Uncommon: dry mouth, headache
Some patients have experienced the following side effects while taking sitagliptin alone: Common: low blood sugar, headache
Uncommon: dizziness, constipation
In addition, some patients have reported the following side effects while taking sitagliptin: Common: upper respiratory infection, stuffy or runny nose and sore throat, osteoarthritis, arm or leg pain.
During post-approval use with Janumet or sitagliptin, one of the medicines in Janumet, additional side effects have also been reported (frequency not known). These side effects have been reported when Janumet or sitagliptin have been used alone and/or as part of combination therapy: allergic reactions, which may be serious, including rash, hives, and swelling of the face, lips, tongue, and throat that may cause difficulty in breathing or swallowing. If you have an allergic reaction, stop taking Janumet and call your doctor right away. Your doctor may prescribe a medicine to treat your allergic reaction and a different medicine for your diabetes. Other side effects that have been reported include: inflammation of the pancreas; kidney problems (sometimes requiring dialysis); vomiting.
Some patients have experienced the following side effects while taking metformin alone: Very common: nausea, vomiting, diarrhoea, abdominal pain and loss of appetite
Common: a metallic taste
Very rare: decreased vitamin B12 levels, hepatitis (a problem with your liver), redness of the skin (rash) or itching, lactic acidosis (excess of lactic acid in your blood) particularly in patients whose kidneys are not working properly. The symptoms include feeling cold or uncomfortable, severe nausea or vomiting, abdominal pain, unexplained weight loss, or rapid breathing
If any of the side effects gets serious, or if you notice any side effects not listed in this leaflet, please tell your doctor or pharmacist.