Side Effects of Mefenamic Acid
Common mefenamic acid side effects may include swelling, increased liver enzymes, and gas. There are also some rare but possible side effects that occur in less than 1 percent of people, including bladder infection, spinning sensation, congestive heart failure, and high blood pressure. Seek medical attention immediately if you experience an allergic reaction, stomach or intestine problems, or unexplained weight gain while taking mefenamic acid.
As with any medicine, side effects with mefenamic acid (Ponstel®). However, not everyone who takes the drug will experience side effects. In fact, most people tolerate it well. If side effects do occur, they are generally minor and either require no treatment or can easily be treated by you or your healthcare provider.
Several factors seem to affect the chances of developing side effects, including a person's:
- Dose of mefenamic acid
- Other medical conditions
- Current medicines.
(This article covers many, but not all, of the possible side effects with mefenamic acid. Your healthcare provider can discuss a more complete list of mefenamic acid side effects with you.)
The U.S. Food and Drug Administration (FDA) warns that people using nonsteroidal anti-inflammatory drugs (NSAIDs) other than aspirin, including mefenamic acid, may have a higher risk of having a heart attack or stroke than those who do not take NSAIDs. This risk may be higher in people taking NSAIDs for a long time. These events can occur without any warning and can lead to loss of life. Get emergency medical help by calling 911 or an ambulance as soon as possible if you experience any of the following symptoms:
- Chest pain
- Shortness of breath
- Weakness on one side of your body
- Slurred speech.
Other possibly serious side effects of mefenamic acid include but are not limited to:
- Allergic reactions, such as:
- Swelling of the face or body
- Unexplained skin rash
- Difficulty breathing
- Stomach or intestine problems, including bleeding, ulcers, or a hole (known as a perforation)
- Liver damage, which can cause:
- Yellowing of the skin or whites of the eyes (jaundice)
- Excessive tiredness
- Kidney problems, including kidney failure
- Fluid retention or unexplained weight gain (see Ponstel and Weight Gain)
- Congestive heart failure.
Because mefenamic acid can increase your risk for major or life-threatening bleeding, contact your doctor immediately if you notice any unusual bleeding or have any of the following symptoms:
- Bloody nose
- Black, tarry stools
- Blood in the urine or stools
- Vomiting blood
- Red or purple spots on the skin.