title: A randomized, quadruple crossover single-blind study on immediate action of chewed and unchewed low-dose acetylsalicylic acid tablets in healthy volunteers.
abstract: In the initial treatment of acute myocardial infarction, it is important to administer oral low-dose acetylsalicylic acid (ASA) within 10 min of arrival at the hospital. However, ASA is supplied as an enteric-coated tablet or buffered tablet to prevent gastric irritation. Although current guidelines recommended that patients should chew their initial dose of ASA, there is little evidence as to whether this is efficacious. Therefore, we aimed to make a direct comparison of the pharmacokinetics and pharmacodynamics of ASA after ingestion of intact and chewed nonenteric-coated buffered ASA tablet (NBA) and enteric-coated ASA tablet (ECA) in a quadruple crossover study in healthy volunteers. Chewing ECA accelerated t(max) of ASA absorption, which became equivalent to that after ingestion of intact or chewed NBA. A significant decrease in serum thromboxane B(2) was observed 20 min after ingestion of chewed ECA, or intact or chewed NBA, and inhibition of platelet aggregation was also observed within 20 min. Thus, chewing of the ECA appears to result in a similar timing of ASA action to that in the case of chewed or unchewed NBA.
authors.affiliation: Department of Hospital Pharmacy, Kanazawa University, Kanazawa 920-8641, Japan. sai-ys@staff.kanazawa-u.ac.jp
authors.forename: Yoshimichi
authors.initials: Y
authors.lastname: Sai
authors.forename: Akiyo
authors.initials: A
authors.lastname: Kusaka
authors.forename: Kaori
authors.initials: K
authors.lastname: Imanishi
authors.forename: Manami
authors.initials: M
authors.lastname: Matsumoto
authors.forename: Rie
authors.initials: R
authors.lastname: Takahashi
authors.forename: Natsumi
authors.initials: N
authors.lastname: Sugimoto
authors.forename: Junko
authors.initials: J
authors.lastname: Sugama
authors.forename: Takako
authors.initials: T
authors.lastname: Anada
authors.forename: Hidesaku
authors.initials: H
authors.lastname: Asakura
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Miyamoto
mesh_terms: D000284:Administration, Oral; D000328:Adult; D019540:Area Under Curve; D001241:Aspirin / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D018592:Cross-Over Studies; D006801:Humans; D008409:Mastication; D008875:Middle Aged; D010974:Platelet Aggregation / Q000187:drug effects; D012016:Reference Values; D016037:Single-Blind Method; D013607:Tablets; D013928:Thromboxane A2 / Q000097:blood
chemical_list: D013607:Tablets; D013928:Thromboxane A2; D001241:Aspirin