Absorption kinetics of low-dose chewable aspirin--implications for acute coronary syndromes

Eur J Clin Invest. 2015 Jan;45(1):13-7. doi: 10.1111/eci.12373.


Background: This study describes the implications of the pharmacokinetics of low-dose chewable aspirin for acute coronary syndromes. Current guidelines recommend the administration of 162-325 mg aspirin chewing tablets for the treatment of acute myocardial infarction. Although aspirin is widely used and a cornerstone in myocardial infarction, there is no information available on the pharmacokinetics of low doses of chewable aspirin.

Materials and methods: This prospective trial assessed the pharmacokinetics of acetylsalicylic acid and its metabolite salicylic acid after intake of 162 mg chewable low-dose aspirin in 35 healthy volunteers. Plasma drug and metabolite levels were analysed using high-performance liquid chromatography, and corresponding pharmacodynamics were determined by impedance aggregometry.

Results: Acetylsalicylic acid was rapidly absorbed with a mean Tmax of 27 ± 8 min. Tmax of salicylic acid was 69 ± 21 min. Mean Cmax was 1·8 ± 0·6 mg/L and 7·6 ± 1·4 for acetylsalicylic acid and salicylic acid, respectively. Arachidonic acid-induced aggregation showed maximum platelet inhibition 30 min after drug ingestion.

Conclusions: The characterization of the plasma-time profile fills the gap between the lack of data on pharmacokinetics and the pharmacodynamics and the recommendation for using low-dose chewable aspirin for acute coronary syndromes. We describe for the first time that a 162-mg dose of chewable aspirin is rapidly absorbed and achieves plasma concentrations of the active metabolite salicylic acid required to maximally inhibit platelet aggregation. However, a 162-mg dose is truly a minimum, and doubling this dose might be better for patients with myocardial infarction.

Keywords: acute coronary syndromes; low-dose chewable aspirin; pharmacokinetics.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Coronary Syndrome / drug therapy*
  • Administration, Oral
  • Adolescent
  • Adult
  • Aged
  • Aspirin / administration & dosage
  • Aspirin / pharmacokinetics*
  • Aspirin / pharmacology
  • Chewing Gum
  • Female
  • Humans
  • Male
  • Middle Aged
  • Platelet Aggregation Inhibitors / administration & dosage
  • Platelet Aggregation Inhibitors / pharmacokinetics*
  • Platelet Aggregation Inhibitors / pharmacology
  • Prospective Studies
  • Young Adult


  • Chewing Gum
  • Platelet Aggregation Inhibitors
  • Aspirin