How Far Is Too Far? The Ethics of Mini Brain Research
December 11, 2025
Brand Name :
Ponstel
Synonyms :
mefenamic acid
Class :
Nonsteroidal Anti-Inflammatory Drugs
Dosage Forms & Strengths
Capsule
250mg
Indicated for Primary Dysmenorrhea:
Initial dose: 500mg orally once then 250mg orally four times a day whenever necessary
Do not exceed for more than three days
Initial dose: 500mg once orally, then 250mg orally four times daily whenever necessary
Do not exceed for more than seven days
Indicated for Primary Dysmenorrhea:
<14 years: Not recommended
>14 years: Initial dose- 500mg orally once, then 250mg orally four times a day whenever necessary
Do not exceed more than three days
Dosage Forms & Strengths
Capsule
250mg
<14 years: Not recommended
>14 years: Initial dose: 500mg orally once, then 250mg orally four times a day whenever necessary
Do not exceed for more than seven days
Initial dose: 500mg orally once then 250mg orally four times a day whenever necessary
Do not exceed for more than seven days
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the nephrotoxic effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the anti-coagulant effect of nonsteroidal anti-inflammatory agents
may decrease the diuretic effect of nonsteroidal anti-inflammatory agents
may decrease the diuretic effect of nonsteroidal anti-inflammatory agents
may decrease the diuretic effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
choline magnesium trisalicylate
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the anti-coagulant effect of nonsteroidal anti-inflammatory agents
may increase the anti-coagulant effect of nonsteroidal anti-inflammatory agents
may increase the anti-coagulant effect of nonsteroidal anti-inflammatory agents
may increase the anti-coagulant effect of nonsteroidal anti-inflammatory agents
may increase the anti-coagulant effect of nonsteroidal anti-inflammatory agents
may decrease the diagnostic effect when combined with metyrapone
triamcinolone acetonide/nystatin
may decrease the therapeutic effect of Antifungal Agents when combined
may decrease the therapeutic effect of Antifungal Agents when combined
methenamine/sodium salicylate/benzoic acid
may decrease the therapeutic effect of Antifungal Agents when combined
may decrease the therapeutic effect of Antifungal Agents when combined
may decrease the therapeutic effect of Antifungal Agents when combined
aprepitant: they may diminish the serum concentration of hormonal contraceptives
may decrease the diagnostic effect of nonsteroidal anti-inflammatory agents
interaction with NSAIDs may lead to increased toxicity such as myelosuppression, renal toxicity, and GI toxicity
interaction with NSAIDs may lead to increased toxicity such as myelosuppression, renal toxicity, and GI toxicity
Hormonal Contraceptives increase the effect of thrombogenesis of tranexamic acid
Could potentially reduce the concentration serum of hormonal contraceptives
the toxicity of either of the drugs is increased due to pharmacokinetic synergism
may increase the nephrotoxic effect of nonsteroidal anti-inflammatory agents
may increase the nephrotoxic effect of nonsteroidal anti-inflammatory agents
may increase the antiplatelet effect of nonsteroidal anti-inflammatory agents
may increase the antiplatelet effect of nonsteroidal anti-inflammatory agents
may increase the antiplatelet effect of nonsteroidal anti-inflammatory agents
may increase the antiplatelet effect of nonsteroidal anti-inflammatory agents
may increase the antiplatelet effect of nonsteroidal anti-inflammatory agents
may decrease the excretion of nonsteroidal anti-inflammatory agents
may decrease the excretion of nonsteroidal anti-inflammatory agents
may decrease the excretion of nonsteroidal anti-inflammatory agents
may decrease the excretion of nonsteroidal anti-inflammatory agents
may decrease the excretion of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the anti-coagulant effect of antiplatelet agents
may increase the anti-coagulant effect of antiplatelet agents
may increase the anti-coagulant effect of antiplatelet agents
may increase the anti-coagulant effect of antiplatelet agents
may increase the anti-coagulant effect of antiplatelet agents
may decrease the anti-hypertensive effect of nonsteroidal anti-inflammatory agents
may decrease the absorption of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
spironolactone and hydrochlorothiazide
may decrease the anti-hypertensive effect of nonsteroidal anti-inflammatory agents
may decrease the anti-hypertensive effect of nonsteroidal anti-inflammatory agents
may decrease the anti-hypertensive effect of nonsteroidal anti-inflammatory agents
may decrease the anti-hypertensive effect of nonsteroidal anti-inflammatory agents
may decrease the anti-hypertensive effect of nonsteroidal anti-inflammatory agents
may increase the antiplatelet effect of antiplatelet agents
may increase the antiplatelet effect of antiplatelet agents
may increase the antiplatelet effect of antiplatelet agents
may increase the antiplatelet effect of nonsteroidal anti-inflammatory agents
may increase the antiplatelet effect of nonsteroidal anti-inflammatory agents
may increase the antiplatelet effect of nonsteroidal anti-inflammatory agents
may increase the antiplatelet effect of nonsteroidal anti-inflammatory agents
may increase the antiplatelet effect of nonsteroidal anti-inflammatory agents
may increase the toxic effect of nonsteroidal anti-inflammatory agents
Combining mefenamic acid with pranlukast may cause a reduction in the mefenamic acid’s metabolism
when bromazepam and mefenamic acid are used together, there is a potential reduction in the bromazepam's metabolism
When loracarbef is used together with mefenamic acid, the risk or seriousness of nephrotoxicity is enhanced
It may enhance the risk of adverse effects when combined with progesterone derivatives
It may enhance the risk of adverse effects when combined with progesterone derivatives
It may enhance the risk of adverse effects when combined with progesterone derivatives
When mefenamic acid is used together with sertraline, the risk or seriousness of bleeding may be enhanced
When mefenamic acid is used together with somatotropin, this leads to a rise in mefenamic acid metabolism
When mefenamic acid is used together with bufexamac, this leads to enhanced risk or seriousness of adverse outcomes
mefenamic acid leads to a reduction in the rate of excretion of nitric oxide, which leads to an increased level of serum
When mefenamic acid is used together with nifenazone, this leads to enhanced risk or seriousness of adverse events
When mefenamic acid is used together with diazoxide, this leads to reduction in therapeutic effectiveness of diazoxide
when both drugs are combined, the risk or severity of adverse effects increases
glycopyrrolate inhaled and formoterol
decreases the serum potassium levels
The thrombogenic action of thalidomide may be increased by hormonal contraceptives
Hormonal contraceptives have the potential to elevate the concentration serum of voriconazole
The concentration serum of flibanserin may be intensified by hormonal contraceptive
the toxicity of either of the drugs is increased due to pharmacokinetic synergism
the serum levels of potassium may be increased
the risk of gastrointestinal bleeding may be increased
When mefenamic acid is aided by hesperetin, it reduces hesperetin’s metabolism
tovorafenib cannot be taken with hormonal contraceptives
may enhance the renal tubular clearance for anionic drug competition
Could potentially lead to a reduction in the concentration serum of hormonal contraceptives
mycophenolate could potentially lead to a reduction in the concentration serum of hormonal contraceptives
Actions and Spectrum:
Frequency defined
>10%
Borderline elevations of one or more LFTs (<15%)
1-10%
Anorexia
Nausea
Gastritis
Constipation
Steatorrhea
Abdominal pain
Diarrhea
Pyrosis
Flatulence
<1%
Eosinophilia
Agranulocytosis
Bone marrow hypoplasia
Leukopenia
Thrombocytopenic purpura
Pancytopenia
Black box warning:
Contraindications/caution:
Contraindications:
The contraindications of mefenamic acid include:
Caution:
Several cautions should be considered when using mefenamic acid, including:
Pregnancy consideration: C
Lactation: Excretion of the drug in human breast milk is known
Pregnancy category:
Category A: well-controlled and Satisfactory studies show no risk to the fetus in the first or later trimester.
Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women.
Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.
Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.
Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.
Category N: There is no data available for the drug under this category
Pharmacology:
Pharmacodynamics:
Pharmacokinetics:
Absorption
mefenamic acid is rapidly and almost completely absorbed following oral administration, with peak plasma concentrations reached within 2-4 hours. Absorption is delayed when mefenamic acid is taken with food, but the extent of absorption is not affected.
Distribution
mefenamic acid is highly protein-bound (more than 90%) to albumin. The volume of distribution is approximately 1 L/kg, indicating that it is mainly distributed in the extracellular fluid compartment.
Metabolism
mefenamic acid is metabolized in the liver through hydroxylation and conjugation reactions to form several metabolites, including the 3′-hydroxymethyl and 3′-carboxyl acid metabolites and their glucuronic acid conjugates. The major metabolite is the 3′-carboxyl metabolite.
Elimination and Excretion
mefenamic acid and its metabolites are eliminated primarily by the kidneys, with approximately 66% of a single dose excreted in the urine and 20-25% excreted in the feces. The elimination half-life is approximately 2 hours.
Administration:
mefenamic acid is usually taken orally in the form of tablets or capsules. The medication can be taken with or without food, but it may be absorbed more slowly and less completely when taken with food
Patient information leaflet
Generic Name: mefenamic acid
Why do we use mefenamic acid?
mefenamic acid is a nonsteroidal anti-inflammatory drug (NSAID) that is used for the relief of pain and inflammation associated with various conditions, including: