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What are the Different Metformin Side Effects?

Meshell Powell
Meshell Powell

Metformin is a prescription medication used to treat diabetes. This medication is easily tolerated by many patients, although some negative side effects are possible. Some potential metformin side effects may include low blood sugar, digestive disorders, or runny nose. Occasionally, more severe metformin side effects may develop. Some of these side effects may include trouble breathing or an irregular heartbeat.

Digestive disturbances are among the most frequently reported metformin side effects. Symptoms may include nausea, vomiting, or stomach cramps. Bloating, gas, and heartburn have also been reported. In many cases, these side effects are mild and do not cause serious problems. If the digestive issues become particularly bothersome, additional medications may be prescribed to combat these side effects so that the patient can continue to take metformin.

Metformin has been shown to cause ovarian cysts in lab rats.
Metformin has been shown to cause ovarian cysts in lab rats.

Cold symptoms such as a runny nose, coughing, or sneezing may also be metformin side effects. These symptoms may go away without treatment after the patient has adjusted to the medication. If these symptoms do not go away or become bothersome, a doctor should be consulted.

Other potential metformin side effects may include headache, muscle pain, or occasional reddening of the skin. Some patients have also reported various types of changes to the fingernails or toenails. An unpleasant taste in the mouth, often described as a metallic taste, is also among the more commonly reported metformin side effects. Preliminary tests show that metformin may cause ovarian cysts in lab rats, although it in not known if humans may develop this side effect as well.

Chest pain or the development of a rash anywhere on the body are rarely reported as metformin side effects, although if these side effects do occur, it should be considered a serious medical emergency. These side effects could indicate a serious health crisis and should be treated immediately. In fact, any troublesome symptoms that develop after beginning to take metformin should be reported to a doctor as soon as possible.

Allergic reactions are rare metformin side effects and constitute an extreme medical emergency. Symptoms such as trouble breathing or hives may indicate an allergic reaction. Other potential signs of an allergic reaction include sudden swelling in any part of the body, especially the face, lips, or throat. An allergic reaction can be fatal if not treated immediately. In some cases, the patient may have to be hospitalized for a few days for close medical monitoring after an allergic reaction.

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    • Metformin has been shown to cause ovarian cysts in lab rats.
      By: Remains
      Metformin has been shown to cause ovarian cysts in lab rats.