What is the pharmacokinetics of aspirin?
Pharmacology/Pharmacokinetics Aspirin is rapidly absorbed in the upper gastrointestinal (GI) tract and results in a measurable inhibition of platelet function within 60 minutes. This antiplatelet effect is associated with prolongation of the bleeding time and inhibition of TXA2-dependent platelet aggregation.
How aspirin is metabolized?
Let’s look at aspirin as example of a drug being metabolised. Aspirin undergoes phase 1 hydrolysis to salicylic acid. In phase 2 it is congugated with either glycine or glucoronic acid forming a range of ionised metabolytes that can then be excreted in the urine.
What are the 4 actions of pharmacokinetics?
Think of pharmacokinetics as a drug’s journey through the body, during which it passes through four different phases: absorption, distribution, metabolism, and excretion (ADME).
What is the distribution of aspirin?
This drug is distributed to body tissues shortly after administration. It is known to cross the placenta. The plasma contains high levels of salicylate, as well as tissues such as spinal, peritoneal and synovial fluids, saliva and milk.
What is pharmacokinetics and pharmacodynamics?
The difference between pharmacokinetics (PK) and pharmacodynamics (PD) can be summed up pretty simply. Pharmacokinetics is the study of what the body does to the drug, and Pharmacodynamics is the study of what the drug does to the body.
Is aspirin an antagonist or agonist?
Aspirin and P2Y12 antagonists are commonly used anti-platelet agents. Aspirin produces its effects through inhibition of thromboxane A2 (TXA2) production, while P2Y12 antagonists attenuate the secondary responses to ADP released by activated platelets.
What affects aspirin metabolism?
High interindividual variation in aspirin (ASA) metabolism and therapeutic response has been observed and is attributed to many factors, including concomitant use of other drugs or alcohol [1], urinary pH [2], sex [3], ethnicity [4], and variants in metabolizing enzymes involved in glucuronidation of ASA metabolites [ …
What are the parameters of pharmacokinetics?
Five pharmacokinetic parameters that are important in therapeutic drug monitoring include:
- Bioavailability. The bioavailability of a drug depends in part on its formulation.
- Volume of distribution and distribution phases.
- Clearance.
- Half-life.
- Protein binding of drugs.
What is the action of aspirin?
Aspirin causes several different effects in the body, mainly the reduction of inflammation, analgesia (relief of pain), the prevention of clotting, and the reduction of fever. Much of this is believed to be due to decreased production of prostaglandins and TXA2.
Is aspirin an antiplatelet?
Aspirin is the “gold standard” antiplatelet agent for prevention of arterial thromboses. The optimum dose of aspirin as an antithrombotic drug can differ in different organ circulations.
What does pharmacokinetics mean in relation to aspirin?
Pharmacokinetics is a term that simply describes what the body does to the drug. This includes how the drug is absorbed, distributed, metabolized, and eliminated. Aspirin is available in oral forms. When taken, it is absorbed in the gastrointestinal tract. It is distributed to all tissues of the body.
Where does the body break down aspirin in the body?
Pharmacokinetics is what the body does to the drug, and pharmacodynamics is what the drug does to the body. Aspirin is absorbed in the GI tract and then distributed to all tissues of the body. It is broken down into salicylic acid, and the liver changes it into metabolites.
Why does aspirin have a short half life?
With increasing total plasma salicylate concentrations, the unbound fraction increases. Salicylate may cross the placental barrier and distributes into breast milk. As mentioned above, aspirin is rapidly biotransformed into the active metabolite, salicylate. Therefore, aspirin has a very short half-life.
How is salicylate metabolized in low doses of aspirin?
The predominant pathway is the conjugation with glycin, which is saturable. With low doses of aspirin approximately 90% of salicylate is metabolized through this pathway. As the maximum capacity of this major pathway is reached, the other pathways with a lower clearance become more important.
