Mefenamic acid
Encyclopedia
Mefenamic acid is a non-steroidal anti-inflammatory drug used to treat pain, including menstrual
pain. It is typically prescribed for oral administration. Mefenamic acid is marketed in the USA as Ponstel.
Mefenamic acid decreases inflammation
(swelling) and uterine
contractions by a still unknown mechanism. However it is thought to be related to the inhibition of prostaglandin
synthesis. There is also evidence that supports the use of mefenamic acid for perimenstrual migraine headache prophylaxis, with treatment starting 2 days prior to the onset of flow or 1 day prior to the expected onset of the headache and continuing for the duration of menstruation
.
Since hepatic metabolism plays a significant role in mefenamic acid elimination, patients with known liver
deficiency may be prescribed lower doses. Kidney
deficiency may also cause accumulation of the drug and its metabolites in the excretory system
. Therefore patients suffering from renal conditions should not be prescribed mefenamic acid.
of mefenamic acid include headache
s, nervousness and vomiting. Serious side effects may include diarrhea
, hematemesis
(vomiting blood), haematuria (blood in urine), blurred vision, skin rash, itching and swelling, sore throat and fever
. It is advised to consult a doctor immediately if these symptom
s appear while taking this medication.
Non-steroidal anti-inflammatory drugs (NSAIDs) may worsen hypertension. Persons with hypertension, left ventricular dysfunction, and heart failure may wish to avoid NSAIDs.
Mefenamic acid is recommended to be taken with food.
Mefenamic acid usage has been discontinued in Germany in 2007 because no study to date could prove any advantage over other NSAIDs, but some severe side-effects have been observed.
, this compound may be synthesized from 2-chlorobenzoic acid
and 2,3-dimethylaniline.
Menstruation
Menstruation is the shedding of the uterine lining . It occurs on a regular basis in sexually reproductive-age females of certain mammal species. This article focuses on human menstruation.-Overview:...
pain. It is typically prescribed for oral administration. Mefenamic acid is marketed in the USA as Ponstel.
Mefenamic acid decreases inflammation
Inflammation
Inflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process...
(swelling) and uterine
Uterus
The uterus or womb is a major female hormone-responsive reproductive sex organ of most mammals including humans. One end, the cervix, opens into the vagina, while the other is connected to one or both fallopian tubes, depending on the species...
contractions by a still unknown mechanism. However it is thought to be related to the inhibition of prostaglandin
Prostaglandin
A prostaglandin is any member of a group of lipid compounds that are derived enzymatically from fatty acids and have important functions in the animal body. Every prostaglandin contains 20 carbon atoms, including a 5-carbon ring....
synthesis. There is also evidence that supports the use of mefenamic acid for perimenstrual migraine headache prophylaxis, with treatment starting 2 days prior to the onset of flow or 1 day prior to the expected onset of the headache and continuing for the duration of menstruation
Menstruation
Menstruation is the shedding of the uterine lining . It occurs on a regular basis in sexually reproductive-age females of certain mammal species. This article focuses on human menstruation.-Overview:...
.
Since hepatic metabolism plays a significant role in mefenamic acid elimination, patients with known liver
Liver
The liver is a vital organ present in vertebrates and some other animals. It has a wide range of functions, including detoxification, protein synthesis, and production of biochemicals necessary for digestion...
deficiency may be prescribed lower doses. Kidney
Kidney
The kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and...
deficiency may also cause accumulation of the drug and its metabolites in the excretory system
Excretory system
The excretory system is a passive biological system that removes excess, unnecessary or dangerous materials from an organism, so as to help maintain homeostasis within the organism and prevent damage to the body. It is responsible for the elimination of the waste products of metabolism as well as...
. Therefore patients suffering from renal conditions should not be prescribed mefenamic acid.
| Brand Names |
|---|
| Mefalth, Mefalth T, Ponstel, Ponstan, Ponstal, Parkemed, Mafepain, Mefamed, Mephadolor, Meftal, Dyfenamic, Potarlon, Dolfenal, Meyerdonal, Alfoxan, Fenagesic, Spiralgin. |
Side effects
Known mild side effectsAdverse drug reaction
An adverse drug reaction is an expression that describes harm associated with the use of given medications at a normal dosage. ADRs may occur following a single dose or prolonged administration of a drug or result from the combination of two or more drugs...
of mefenamic acid include headache
Headache
A headache or cephalalgia is pain anywhere in the region of the head or neck. It can be a symptom of a number of different conditions of the head and neck. The brain tissue itself is not sensitive to pain because it lacks pain receptors. Rather, the pain is caused by disturbance of the...
s, nervousness and vomiting. Serious side effects may include diarrhea
Diarrhea
Diarrhea , also spelled diarrhoea, is the condition of having three or more loose or liquid bowel movements per day. It is a common cause of death in developing countries and the second most common cause of infant deaths worldwide. The loss of fluids through diarrhea can cause dehydration and...
, hematemesis
Hematemesis
Hematemesis or haematemesis is the vomiting of blood. The source is generally the upper gastrointestinal tract. Patients can easily confuse it with hemoptysis , although the latter is more common.-Signs:...
(vomiting blood), haematuria (blood in urine), blurred vision, skin rash, itching and swelling, sore throat and fever
Fever
Fever is a common medical sign characterized by an elevation of temperature above the normal range of due to an increase in the body temperature regulatory set-point. This increase in set-point triggers increased muscle tone and shivering.As a person's temperature increases, there is, in...
. It is advised to consult a doctor immediately if these symptom
Symptom
A symptom is a departure from normal function or feeling which is noticed by a patient, indicating the presence of disease or abnormality...
s appear while taking this medication.
Non-steroidal anti-inflammatory drugs (NSAIDs) may worsen hypertension. Persons with hypertension, left ventricular dysfunction, and heart failure may wish to avoid NSAIDs.
Mefenamic acid is recommended to be taken with food.
Mefenamic acid usage has been discontinued in Germany in 2007 because no study to date could prove any advantage over other NSAIDs, but some severe side-effects have been observed.
Overdose
Overdose can lead to a range of symptoms including convulsions, nausea, vomiting, vomiting blood, shallow breathing, coma. Onset of symptoms is usually between 30 minutes and 4 hours, but signs of renal failure may appear several days after an overdose. Seek medical attention immediately in the case of overdose. The lethal dose can be as low as 2.5g.Synthesis
Analogous to fenamic acidFenamic acid
Fenamic acid is a molecule which serves as a parent structure for several non-steroidal anti-inflammatory drugs, including mefenamic acid, tolfenamic acid, flufenamic acid, and meclofenamic acid....
, this compound may be synthesized from 2-chlorobenzoic acid
2-Chlorobenzoic acid
2-Chlorobenzoic acid is a simple organic compound which can be used as a chemical building block. It may be synthesized by the oxidation of 2-chlorotoluene with potassium permanganate.It can be synthesized by diazotization. It follows Sandmeyer reaction....
and 2,3-dimethylaniline.
Sources
- MedlinePlus Drug Information: Mefenamic Acid. Last accessed September 28, 2005.
- Ponstel Pharmacology, Pharmacokinetics, Studies, Metabolism - Mefenamic Acid - RxList Monographs. Last accessed September 28, 2005.
- Consumption of NSAIDs and the Development of Congestive Heart Failure in Elderly Patients
- NSAIDs May Increase Risk for Worsening Heart Failure