WHEN NOT TO GIVE ASPIRIN
Ex. Hon. Physician, Jaslok Hospital and Bombay Hospital,
Mumbai, Ex. Hon. Prof. of Medicine, Grant Medical College and JJ Hospital, Mumbai
Most of the practitioners prescribe Aspirin
without thinking twice. I feel amused whenever I remember that, 35 years ago,
at Grant Medical College, I had taken a post graduate clinic for four hours
on this subject- "should the prescription of Aspirin be stopped in private
practice because of hazards and side effects of this drug?" At that time,
there were many reports of acute liver failure (Reye’s syndrome) in small children
and anaphylactic shock following use of Aspirin.
The tables turned during last 20 years. Aspirin has become a life saving prescription
for patients having IHD and those presenting with brain stroke and many other
Nobody knows the real dose of Aspirin. There was a time when in neurology the
dose was supposed to be 600 mg. Later on, this was reduced to 300 mg. Today,
a neurologist prefers a low dose of 75 mg just like a Cardiologist does.
One thing is definite. 300 mg tablet might be given to chew if you are suspecting
myocardial infarction, but on the whole, the dose in modern prescription is
150 mg or less (upto 50 mg). Most of the practitioners think that the dose was
reduced as in the case of many other drugs (Pyrazinamide, Thiacetazone, Streptomycin
injections, oral or injectable steroids, NSAID group of drugs, anti-diabetic
drugs and many others) where "more" side effects appear when larger
doses of the drugs are given. This is not true.
In case of Aspirin, the toxicity is seen only in rheumatic fever when very high
doses of 6000-8000 mg are prescribed. In this situation, the patient can die
of haemorrhage due to prolonged prothombin time or severe metabolic acidosis.
Otherwise, even six to eight tablets of Aspirin per day cannot cause toxicity.
The low dose of new preparations is being introduced because the "anti-platelet
action" of Aspirin appears to be better at a low dose than at "higher
I am writing this article to impress the practitioners, "when not to prescribe
Aspirin" even in the lowest dose of 50 mg tablet which is now available
in the market.
The most common mistake which the practitioners do is to give an Aspirin tablet
to a patient who is diagnosed as TIA (Transient Ischaemic Attack). Remember
that TIA is a retrospective diagnosis and the tablet should be given only after
1 hour when the symptoms have already subsided. The tablet is given to prevent
future TIAs and permanent neurological deficit. If the patient’s symptoms are
due to a small cerebral haemorrhage and aspirin tablet is given, the bleeding
in the brain can increase markedly. In a hospital and/or in an affording patient
if imaging facilities are very easily available, and if a brain scan is reported
normal, Aspirin can be prescribed earlier for TIA with confidence.
The second situation is a patient who is having severe hypertension, e.g. 200/120
mm Hg. Whether the patient has neurological symptoms or chest symptoms (where
the differential diagnosis could be "dissection of the aorta"), it
will be better to withhold the prescription of Aspirin.
In a patient with chest symptoms, it will be easier to remember that if the
patient has very severe excruciating chest pain, then only dissection of the
aorta, pericarditis, rupture of the oesophagus come in the differential diagnosis.
Fortunately, most of the patients of myocardial infarction complain of "only"
severe heaviness associated with profuse sweating, nausea or vomiting and can
be given Aspirin. Aspirin should be avoided if the BP is very high. Aspirin
should be avoided if the patient uses the word "burning" for chest
pain, because it can increase oesophagitis (which is the usual cause of burning
In a patient who has history of ulcer or chronic hyperacidity (where the cause
is very often oesophagitis - GERD syndrome with or without lax hiatus or hiatus
hernia), Aspirin can increase the symptoms and even cause GI bleeding.
It is worth remembering that even in a normal person, in a very small dose of
50-75 mg, Aspirin can cause massive, upper GI bleed, not responding to blood
transfusions and other treatment and thus prove fatal.
This "poison" should be prescribed "life time" only to those
patients who really deserve this prescription. Nowadays, I often find practitioners
prescribing aspirin to young businessmen and executives aged around thirty to
prevent a heart attack! This is wrong because you expect the patient to take
Aspirin for 40 years without developing any side effects, which is often not
In my practice, I find that more than 1/3 of the patients who are on long term
Aspirin, develop iron deficiency anaemia. This is because every tablet of Aspirin
causes gastric oozing and a very small amount of blood is lost which the body
easily compensates. But in others, this oozing could be much more and with the
occult blood loss in the stool, the patient becomes anaemic. Now, depending
on the urgency and the importance of the indication in a particular patient,
if the Hb goes down to 11 gm in a male patient inspite of additional dose of
iron, it is time to stop Aspirin. Nowadays, Clopidogrel can always be used as
substitute if the patient can afford to spend for it life time. The long term
haematological side effects of this drug have still not been described.
Aspirin must always be stopped for 2-3 days before any surgery (including CABG
bypass surgery) is carried out. There are plenty of chances that the patient
will bleed excessively during the surgery. The most common mistake which was
being made and which is now being corrected, was that the patients were being
operated for cataract while they were on Aspirin. These patients will develop
bleeding complications which are dangerous for the vision.
If the patient develops frequent urticaria following Aspirin, this drug should
be stopped, lest the patient may develop angio-neurotic oedema and die of the
In a stroke patient, who is paralysed or semi-conscious, never prescribe Aspirin
without making sure that the brain scan shows no evidence of haemorrhage.
On the whole, I would like the practitioners to treat this drug as a "dangerous
drug". Make sure that the patient takes it after breakfast and not on empty
stomach. Keep a watch the Hb when the patient is on life time Aspirin. Diagnose
upper GI bleed at the earliest by the symptoms of melaena and stop the drug
immediately. Do not prescribe this drug life time unless definitely indicated.