Mefenamic Acid - Uses and Side Effects

Introduction:

Mefenamic acid is a pharmaceutical drug that belongs to a class of medications called non-steroidal anti-inflammatory drugs (NSAID) and is used to treat pain, specifically menstrual pain. The menstrual cycle is a series of events in a female body, preparing women for pregnancy. The drug attempts to relieve the pain caused due to muscle cramps during the menstrual cycle and also helps to relieve any associated symptoms. The drug was first approved by the Food and Drug Administration (FDA) on 19th February 2008.

This article extensively briefs about Mefenamic acid as a helpful therapy option for those suffering from menstrual pain. It additionally covers the mechanism of action, available dosage, dosage forms, usage, potential adverse effects, and precautions. Understanding the advantages and factors to be considered when using this medicine will help patients and healthcare professionals make well-informed decisions to manage pain as effectively as possible.

Drug Group

Mefenamic acid belongs to a class of anthranilic acid, a derivative class of non-steroidal anti-inflammatory drugs. It is a cyclooxygenase inhibitor. It blocks both COX-1 (cyclooxygenase 1) and COX-2 (cyclooxygenase 2). It inhibits the production of intracellular prostaglandins, which play a crucial role in mediating pain and inflammatory pathways.

Available Doses and Dosage Forms:

The drug is available in varying doses specific to each country. Some commonly available doses include 250 milligrams and 500 milligrams. The drug is available in the form of tablets and capsules. A particular dose will be recommended according to each patient's unique condition, the intensity of their symptoms, and how they react to therapy. To ensure the safety and effective use of the drug, patients must carefully follow the dose recommendations made by their healthcare professionals.

For Patients:

What Is Pain?

Pain is a sensory experience that occurs when the body damages its tissues. It is a protective mechanism that alerts the body about potential harm or injury. Pain can be acute or chronic.

How Does Mefenamic Acid Work?

The mechanism of action of the drug is mentioned below:

The drug works by inhibiting the enzyme cyclooxygenase (COX). The enzyme has two isoforms, which are COX-1 and COX-2.

• COX-1 is essential for maintaining physiological functions, which include protecting the stomach lining and regulating the blood platelet count.

• COX-2 is usually produced at the inflammatory site and produces prostaglandins, primarily for promoting pain, inflammation, and swelling.

The drug inhibits both COX-1 and COX-2, alleviating pain and reducing inflammation. This makes the drug highly effective in treating menstrual pain and other musculoskeletal pain.

What Is the Dosage of Mefenamic Acid?

• Adult Dosage - The starting drug dosage in adults is usually 500 mg (milligram), once daily, followed by 250 mg six hourly, if required, for two to three days or as long as the pain lasts.

• Child Dosage - The dosage is usually about five to ten milligrams per kilogram of body weight in children. The total dosage should not exceed thirty milligrams per kilogram of body weight.

• Dosage Modifications - The dosage may be modified according to individual factors like the severity of pain and other medical conditions or medications the person takes. In addition, age-related factors, body weight, and kidney and liver function may also influence the appropriate dosage.

How Effective Is Mefenamic Acid?

The drug is effective in relieving pain, and also it helps to subside inflammation. The effects of the drug are specifically noticed in treating the following conditions:

• Musculoskeletal Pain - It helps relieve pain in conditions like arthritis, sprain, and muscle strains.

• Menstrual Pain - It helps manage menstrual pain by reducing the production of prostaglandins which cause uterine contractions.

• Headaches - The anti-inflammatory and analgesic property helps to relieve headache and migraine.

• Postoperative Pain - The drug is used in the short-term management of surgical procedures.

How Is Mefenamic Acid Administered?

The drugs are available only in the form of oral formulations. Hence, it must be taken as per the doctor's prescription with food in the morning. It is better to consume the drug at the same time every day.

What Are the Side Effects of Mefenamic Acid?

A few side effects of the drug are listed below:

• Allergic Reactions - Although it is a rare side effect of the drug, it is important to seek medical attention for quick relief.

• Drowsiness - Some individuals are known to feel drowsy after the drug administration. In such cases, avoiding driving or operating heavy machinery is better.

• Gastrointestinal Issues - It is the most common side effect of Mefenamic acid. It may cause symptoms like nausea, vomiting, diarrhea, and heartburn. The drug is known to irritate the stomach lining and may potentially lead to ulcers or bleeding.

• Kidney Ailments - The drug may cause kidney ailments in individuals with pre-existing kidney problems and at a higher risk of heart disease.

What Are the Things to Inform the Doctor Before Taking the Drug?

The following are the most important details to tell the doctor:

• Allergies: Patients should detail all known allergies to foods, drugs, and other substances. This includes any prior negative drug interactions with antispasmodics (medicines that calm down muscle spasms) or similar agents.

• Medical History: Patients must give relevant information about their health history, including current or previous problems. If a patient has a history of heart, liver, kidney, or any other pertinent problems, they should specifically let their doctor know.

• Current Medications: Patients should inform the physician about any prescription pharmaceuticals, over-the-counter medicines, dietary supplements, or herbal items they use. Mefenamic acid and other drugs may interact, which might have adverse effects or lessen their efficacy.

• Breastfeeding and Pregnancy: Patients who want to become pregnant or are nursing should talk to their doctor about these matters. Mefenamic acid's safety during pregnancy and breastfeeding has not been thoroughly proven, and the doctor can weigh the advantages and disadvantages.

• Surgery: Patients should notify their doctor or surgeon about using Mefenamic acid if they plan any surgical operations, including dental surgery, since this might affect the anesthesia or other drugs used.

• Functions of Liver and Kidneys: Patients who suffer from liver or renal dysfunction should inform their doctor about any impairment in these organs. In certain circumstances, dosage modifications may be required.

• Alcohol Use: Patients should be honest with their doctors about their alcohol use since it may interact with Mefenamic acid and worsen some adverse effects.

• Hypersensitivity: Patients should talk to their doctor if they ever have a hypersensitivity reaction to a medicine.

Dietary Considerations:

• It is advised to take Mefenamic acid with meals. However, taking it an hour or so before meals may cause gastrointestinal spasms, acid reflux, and related symptoms.

• While using Mefenamic acid, it is best to refrain from drinking because alcohol may interact with the drug and worsen some adverse effects.

• Some may discover that particular meals or drinks may worsen their stomach issues. To uncover potential dietary components that influence symptom management, keeping a food diary and recording any triggers is beneficial.

• Maintaining a balanced, healthy diet of fiber, fruits, and vegetables can improve gastrointestinal health. Still, talking with a doctor about specific dietary needs is essential, especially if the patient has underlying digestive problems or dietary restrictions.

Missed Dose:

If a dose of Mefenamic acid is missed, the patient should take it as soon as they remember. However, if it is almost time for the next scheduled dose, they should skip the missed dose and resume their regular dosing schedule. Taking a double dose to compensate for the missed one should be avoided.

Overdose:

In the event of an overdose, which can lead to severe side effects, individuals should promptly seek immediate medical attention or contact a poison control center. Overdose symptoms may include a pronounced dry mouth, rapid or irregular heartbeat, fever, confusion, hallucinations, and difficulty swallowing or speaking.

Storage and Disposal:

• Mefenamic acid must be stored at room temperature, away from moisture and direct sunlight. Keep the medication out of reach of children and pets.

• Do not use Mefenamic acid after the expiration date stated on the packaging.

• If unused or expired medications exist, individuals should follow proper disposal guidelines as instructed by local regulations or a healthcare professional.

• Unless specifically directed, they should avoid flushing them down the toilet or pouring them into drains.

For Doctors:

Indication:

Mefenamic acid treats menstrual pain, neuromuscular pain, and its symptoms. It is categorized as a non-steroidal anti-inflammatory drug that inhibits prostaglandins, thereby preventing the pain and inflammatory medications caused by it.

Dose:

The medical professional decides the dosage to be administered based on the patient's condition, the intensity of their symptoms, and how they react to the therapy. The dose for adults is often 500 milligrams (mg) administered orally once daily. The dosage may be repeated depending on the severity of the symptoms and pain.

What Are the Pharmacological Aspects of Mefenamic Acid?

1. Mechanism:

Mefenamic acid is an NSAID that blocks the secretion of prostaglandins to alleviate menstrual pain and prevent muscle cramps. This helps an individual to feel no pain during menstruation.

2. Pharmacokinetics:

• Mefenamic acid is given orally in tablet or capsule form, and the gastrointestinal tract readily absorbs it.

• The drug is metabolized in the liver through hepatic metabolism, which results in active metabolites that support the medication's pharmacological effects.

• A tiny amount of the medicine is removed from the feces, but most of it is excreted in the urine.

• The dose regimen and interval are influenced by the pharmacokinetic features of Mefenamic acid, ensuring optimal levels of the medicine for symptom alleviation while preventing excessive drug buildup.

3. Toxicity:

• Mefenamic acid is typically well tolerated when administered at therapeutic levels to treat pain.

• The most commonly reported clinical side effects include headache, nausea, vomiting, stomach ulcers, and drowsiness.

• Some people may develop more severe clinical side effects, including allergic reactions and kidney ailments. Such patients should seek quick medical assistance if these significant adverse effects manifest.

4. Drug Interactions:

• The combined use of the drug with Aspirin may increase the gastrointestinal side effects.

• The drug interacts with anticoagulants and increases the risk of bleeding.

• Mefenamic acid may decrease the elimination of lithium resulting in lithium toxicity.

• The drug increases the levels of Cyclosporine, which is used to suppress the immune system after organ transplantation.

5. Clinical Studies:

The drug has undergone various clinical studies to assess its effectiveness in treating menstrual and neuromuscular pain. The drug effectively relieved pain and inflammation caused by dysmenorrhea or menstrual pain. The drug is known to have excellent actions compared to its counterparts, as it inhibits COX-1 and COX-2.

What Are the Contraindications?

Mefenamic acid contraindications include:

• Individuals with a history of allergy or hypersensitivity should avoid using this drug.

• The drug is metabolized in the liver, so individuals with severe liver impairment should avoid using the medication.

• The use of this drug with Aspirin is contraindicated due to the risks like gastrointestinal ulcers and bleeding.

• Pregnant and breastfeeding should avoid this drug during the third trimester, as it may harm the fetus.

Considerations for Dosing:

• Patients who are elderly or have specific medical issues could need lower initial dosages, and the dosage can be changed as necessary.

• Mefenamic acid is typically not advised for use in children unless expressly prescribed; hence, a pediatric physician should establish the dosage and administration for pediatric patients.

• Mefenamic acid should be taken exactly as the doctor suggests, and the recommended dosage should not be increased.

• Even if symptoms improve, patients should keep taking Mefenamic acid for the entire period the doctor recommends.

• It is not advisable to stop taking the drug suddenly without first talking to a doctor because it might cause withdrawal symptoms to recur.

• Any other prescription drugs, dietary supplements, or herbal items must be disclosed to the healthcare professional since they may interact with Mefenamic acid.

Specific Considerations:

• Patients should abstain from drinking alcohol while taking Mefenamic acid since the drug's adverse effects may be exacerbated by alcohol.

• Older patients may be more vulnerable to Mefenamic acid's side effects and interactions with other drugs. There may arise a need for dose modifications or close monitoring.

• Ad adheres to the healthcare provider's recommendations to reduce the danger of potential drug interactions.

• Any odd symptoms or side effects while taking Mefenamic acid should be reported immediately to the patient's healthcare practitioner for further analysis.