This is with reference to the advertisement in the November issue of
Indian Pediatrics, wherein Mefenamic acid has been proclaimed as "The
Preferred Antipyretic". Mefenamic acid is not the preferred antipyretic,
for the following reasons:
Safety: This drug can cause frank colitis in
patients with no known predisposing factors(1) and generalized tonic
clonic seizures in overdose. Mucosal damage may result from impairment of
local prostaglandin synthesis and disturbance of the equilibrium between
the cyclo - and lipoxygenase pathways of arachidonic acid metabolism.
Reports of acute renal failure due to mefenamic acid, have appeared
steadily over the past 15 years(2). Most patients presented with abdominal
pain and diarrhea and were not oliguric; not all cases were reversible.
Even recently eminent journals continue to publish case reports on the
side effects of mefenamic acid in children(3).
Indications: The literature search on the
indications of mefenamic acid quotes others like mild to moderate pain in
acute and chronic conditions including: pain of traumatic, arthritic or
muscular origin; dysmenorrhea; headache and dental pain, reducing blood
loss in menorrhagia due to ovulatory dysfunctional bleeding rather than as
an antipyretic (Wikipedia Drug Formulary).
Contraindications: It is also
contraindicated in patients with a history of gastro-intestinal bleeding
and or inflammatory bowel disease. Broncho-constriction may occur in
asthmatic patients with aspirin sensitivity. Mefenamic acid affects
platelet function and it may enhance the effect of anti-coagulant therapy
which means that it is deleterious in dengue fever and other hemorrhagic
fevers which are quite prevalent in present day scenarios. The
advertisement quotes it to be given in malaria which in itself can cause
thrombocytopenia. It may not be appropriate to use NSAIDs for fever
following immunization particularly in young infants.
Preferred antipyretic: Paracetamol has been
quoted as the safest antipyretic in children(4) and hence mefenamic acid
should not be promoted as the preferred antipyretic.
References
1. Hall RI, Petty AH, Cobden I, Lendrum R. Enteritis
and colitis associated with mefenamic acid. BMJ 1983; 287: 1182.
2. Robertson CE, Ford MJ, Van Someren V, Dlugolecka M,
Prescott LF. Mefenamic acid nephropathy. Lancet 1980; ii: 232-233.
3. Onay OS, Erçoban HS, Bayrakci US, Melek E, Cengiz N,
Baskin E. Acute, reversible nonoliguric renal failure in two children
associated with analgesic-antipyretic drugs. Pediatr Emerg Care 2009; 25:
263-266.
4. Chandra J, Bhatnagar SK. Antipyretics in children. Indian J Pediatr
2002; 69: 69-74.