What is Acetylsalicylic Acid (Aspirin)?

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From the Guidelines

Aspirin is a nonsteroidal anti-inflammatory drug (NSAID) that is primarily used as a pain reliever, fever reducer, and anti-inflammatory agent, and it also has antiplatelet effects that make it useful for preventing heart attacks and strokes in high-risk individuals. It belongs to a class of drugs called NSAIDs and contains the active ingredient acetylsalicylic acid. Aspirin is typically available in doses ranging from 81 mg (low-dose or "baby" aspirin) to 325 mg (regular strength) 1. It works by blocking certain chemicals in the body that cause inflammation and pain by inhibiting enzymes called cyclooxygenases, which produce prostaglandins that promote inflammation, pain, and fever.

Some of the key benefits of aspirin include its ability to reduce the risk of heart attacks and strokes in high-risk individuals, as well as its potential to prevent colorectal cancer 1. However, aspirin can also have side effects, such as stomach irritation, heartburn, and increased risk of bleeding, which is why it should be taken with food and avoided by people with bleeding disorders or those taking other blood thinners unless directed by a doctor 1.

The use of aspirin for primary prevention of cardiovascular disease is a topic of ongoing debate, with some guidelines recommending its use in certain high-risk individuals, while others do not 1. For example, the American College of Cardiology (ACC) and the American Heart Association (AHA) recommend low-dose aspirin for primary prevention of cardiovascular disease in adults aged 40-70 years who have an increased risk of cardiovascular disease and no increased risk of bleeding.

Some of the key factors to consider when deciding whether to use aspirin for primary prevention of cardiovascular disease include the individual's risk of cardiovascular disease, their risk of bleeding, and their overall health status. The most recent and highest quality study on this topic, published in 2023, recommends using coronary artery calcium (CAC) scores to guide aspirin therapy, with aspirin recommended for individuals with a CAC score of 100 or higher 1.

In terms of specific dosing recommendations, the usual dose of aspirin for pain relief is 325-1000 mg every 4-6 hours as needed, while the dose for cardiovascular prevention is typically 81-100 mg daily. It is essential to follow the recommended dosage and consult with a healthcare provider before starting aspirin therapy, especially for individuals with certain medical conditions or taking other medications.

Overall, aspirin is a commonly used medication that has both benefits and risks, and its use should be carefully considered on an individual basis, taking into account the latest evidence and guidelines. The key to maximizing the benefits of aspirin while minimizing its risks is to use it judiciously and under the guidance of a healthcare provider.

From the FDA Drug Label

Active Ingredient (in each tablet) Aspirin 81 mg (NSAID)nonsterodial anti-inflammatory drug

  • Aspirin is a nonsteroidal anti-inflammatory drug (NSAID).
  • It is the active ingredient in the medication, with a dose of 81 mg per tablet. Aspirin is an NSAID 2.

From the Research

Definition of Aspirin

  • Aspirin is also known as acetylsalicylic acid (ASA) 3, 4, 5, 6
  • It is a widely used drug for its anti-inflammatory, antipyretic, and analgesic properties 4, 5

Medical Uses of Aspirin

  • Aspirin is used to prevent cardiovascular diseases, including coronary heart disease, previous myocardial infarction, previous stroke, and peripheral atherosclerosis 4
  • It is also used to treat acute myocardial infarction, unstable coronary heart disease, coronary artery bypass surgery, and angioplasty, as well as to treat acute stroke 4
  • Aspirin is used to treat headache, including migraine, and has undergone an evolution in its formulation to improve its efficacy and convenience 5

Properties of Aspirin

  • Aspirin works by irreversibly inhibiting the key enzyme of arachidonic acid cascade, a prostaglandin H synthetase, also called cyclooxygenase (COX) 4
  • It has antiplatelet effects, which can help reduce the risk of ischemic events, but also increases the risk of bleeding 3, 4

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

[Acetylsalicylic acid in the prevention and treatment of cardiovascular diseases].

Wiadomosci lekarskie (Warsaw, Poland : 1960), 2018

Research

Acetylsalicylic acid in the treatment of headache.

Cephalalgia : an international journal of headache, 1999

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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