Skip to main content

Riomet ER Side Effects

Generic name: metformin

Medically reviewed by Drugs.com. Last updated on Jun 11, 2024.

Note: This document provides detailed information about Riomet ER Side Effects associated with metformin. Some dosage forms listed on this page may not apply specifically to the brand name Riomet ER.

Applies to metformin: oral solution, oral suspension extended release, oral tablet, oral tablet extended release, oral tablet extended release 24 hr.

Important warnings This medicine can cause some serious health issues

Oral route (tablet; tablet, extended release; solution; suspension, extended release)

Death, hypothermia, hypotension, and resistant bradyarrhythmias have been reported due to metformin-associated lactic acidosis.

Onset may be subtle and include nonspecific symptoms such as malaise, myalgia, respiratory distress, somnolence, and abdominal distress; laboratory abnormalities include low pH, increased anion gap and elevated blood lactate.

The risk of lactic acidosis increases with renal or hepatic impairment, aged 65 years or older, having a radiological study with contrast, surgery, or other procedures, hypoxic states, and excessive alcohol intake.

If lactic acidosis is suspected, metformin hydrochloride should be discontinued, supportive measures started in a hospital setting.

Prompt hemodialysis is recommended.

Serious side effects of Riomet ER

Along with its needed effects, metformin (the active ingredient contained in Riomet ER) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking metformin:

More common side effects

  • abdominal or stomach discomfort
  • cough or hoarseness
  • decreased appetite
  • diarrhea
  • fast or shallow breathing
  • fever or chills
  • general feeling of discomfort
  • lower back or side pain
  • muscle pain or cramping
  • painful or difficult urination
  • sleepiness

Less common side effects

  • anxiety
  • blurred vision
  • chest discomfort
  • cold sweats
  • coma
  • confusion
  • cool, pale skin
  • depression
  • difficult or labored breathing
  • dizziness
  • fast, irregular, pounding, or racing heartbeat or pulse
  • feeling of warmth
  • headache
  • increased hunger
  • increased sweating
  • nausea
  • nervousness
  • nightmares
  • redness of the face, neck, arms, and occasionally, upper chest
  • seizures
  • shakiness
  • slurred speech
  • tightness in the chest
  • unusual tiredness or weakness

Rare side effects

  • behavior change similar to being drunk
  • difficulty with concentrating
  • drowsiness
  • lack or loss of strength
  • restless sleep
  • unusual sleepiness

Other side effects of Riomet ER

Some side effects of metformin may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common side effects

  • acid or sour stomach
  • belching
  • bloated
  • excess air or gas in the stomach or intestines
  • full feeling
  • heartburn
  • indigestion
  • loss of appetite
  • metallic taste in the mouth
  • passing of gas
  • stomachache
  • stomach upset or pain
  • vomiting
  • weight loss

Less common side effects

  • abnormal stools
  • bad, unusual, or unpleasant (after) taste
  • change in taste
  • difficulty with moving
  • discoloration of the fingernails or toenails
  • flu-like symptoms
  • joint pain
  • rash
  • sneezing
  • stuffy or runny nose
  • swollen joints

For healthcare professionals

Applies to metformin: compounding powder, oral solution, oral suspension extended release, oral tablet, oral tablet extended release.

General adverse events

Gastrointestinal events such as nausea, vomiting, diarrhea, abdominal pain, and loss of appetite have been frequently reported during therapy initiation and resolve spontaneously in most cases.

Adverse events in the pediatric population appear to be similar in nature and severity to that published in adults.[Ref]

Metabolic

Gastrointestinal

Hematologic

Other

Hepatic

Cardiovascular

Dermatologic

Endocrine

Immunologic

Musculoskeletal

Nervous system

Psychiatric

Respiratory

References

1. (2001) "Product Information. Glucophage (metformin)." Bristol-Myers Squibb

2. Cerner Multum, Inc. "UK Summary of Product Characteristics."

3. Cerner Multum, Inc. "Australian Product Information."

4. (2014) "Product Information. Fortamet (metformin)." Physicians Total Care

5. (2014) "Product Information. Glumetza (metformin)." Biovail Pharmaceuticals Canada

6. (2014) "Product Information. Riomet (metformin)." Ranbaxy Pharmaceuticals

Frequently asked questions

Further information

Riomet ER side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.