Aspirin – Revisited

Aspirin is a household name all over the world. This tablet contains acetyl salicylic acid. Interestingly it was historically extracted from willow park but is also contained in several other plants. There is a mention of this agent from times immemorial from 2000 BC “Third dynasty of Ur”.

However, its wide availability in the market was brought out by Dr Felix Hoffmann, a German Chemist for synthetizing it. It is speculated by many that Dr Hoffmann did it under the guidance of Arthur Eichengrun, who first published it in a scientific forum. Dr Arthur was an ex-employee of Bayer pharmaceuticals.

Bayer patented it in 1899 and is still selling it worldwide as Bayer Aspirin. It is off patent for several decades now and is manufactured by several companies. It is one of the cheapest remedies for fever and pain at a cost of 60 paise per pill.

The dose needed is 300 to 150 mgs repeated a few times per day till required. It is also invaluable in treating acute rheumatic fever and associated joint inflammation, where it is needed in much higher doses for 4 to 6 weeks. Corticosteroids are often preferred for this because of more pronounced effect and being much more palatable.

Its use as a pain killer and fever treating medicine has declined considerably after the availability of paracetamol and ibuprofen and a host of non-steroidal analgesics.

Aspirin as a Blood Thinner:

It was in 1971 that a British pharmacologist Dr john Robert Vane     discovered the property of suppressing the prostaglandins and thromboxane. For this he received Nobel prize in physiology and medicine in 1982. This property of inhibiting the platelet aggregation makes it a very useful agent for treating heart attacks, unstable angina, ischemic strokes and in preventing clot formation after putting in stents in the coronary arteries. A single tablet of aspirin administered within an hour of the onset of a heart attack can reduce the mortality by 20% and is thus strongly encouraged. Following a heart attack, after bypass surgery or angioplasty it is used indefinitely to prevent another event. This is called secondary prevention.

Interestingly all this is achievable at a low doses of 75 to 100 mgs per day. It is often combined with drugs like clopidogrel, ticagrelor or prasugrel for 6 to 12 months (dual anti-platelet therapy) after an angioplasty or bypass surgery. However, aspirin is continued indefinitely.

ASPIRIN for Preventing a Heart Attack

This had become a common indication especially in high-risk persons like diabetics, elderly, persons with a family history of vascular events etc.However, in the last decade a number of well-designed trials have made this indication controversial. While the drug does confer some benefit but its adverse effects of increasing bleeding often nullify it. it is not recommended for general use. The risk benefit is to be weighed by the treating physician before recommending it in a given person for primary prevention.

Thus, the dictum “An aspirin a day keeps doctor away” is no longer considered true. The other down sides of aspirin can be stomach intolerance, bronchial asthma, allergy and resistance.

Miscellaneous uses of Aspirin and current status:

Prevention of cancers, especially Colo-rectal, breast, endometrial and prostate cancers. This belief based upon small studies persisted ill recently when a large study of 2018“ASPREE” showed it was not true and if at all there was an increase. Therefore,it no longer is recommends for this use.

Its use in bipolar disorders and depression based upon small series has been negated by large meta-analysis on this subject. Likewise, its role in dementia and schizophrenia has not been sustainedby specific studies.

Its utility in retinal vein thrombosis a serious vision disorder due to thrombosis once widely advocated has been questioned and no longer recommended. In fact, the Royal College of Ophthalmologists has also not recommended  it and described it as potentially harmful.

Interactions with other drugs:

Aspirin can alter the potency of several anti-diabetics, anti-coagulants like warfarin and corticosteroids and this needs to be kept in mind. 

Tailpiece:

Acetyl salicylic acid though known to mankind since 2000BC became available as a tablet for around 125 years now.It has been largely replaced by other drugs for managing fever and pains. Most of its other uses have declined considerably because of several better evidence-based molecules becoming available. Despite its antiquity it is however still one of the essential and sheet anchor drugs in the long-termmanagement of heart attacks and vascular events. Another place which is its forte is after coronary artery bypass surgery and angioplasty alone or in combination with other blood thinners.

DISCLAIMER: The views and opinions expressed in this article are the personal opinions of the author.

The facts, analysis, assumptions and perspective appearing in the article do not reflect the views of GK.