1 FARMAKOKINETIKA PERTEMUAN 2 KONSEP FARMAKOKINETIKA

Summary

This lecture introduces pharmacokinetics, the study of how drugs and their metabolites change in the body over time. Key concepts covered include absorption, distribution, metabolism, and excretion (ADME). The lecturer explains how drugs move through the body, emphasizing the roles of enzymes like cytochrome P450 in metabolism. The importance of pharmacokinetics in drug development, therapeutic drug monitoring (TDM), and ensuring the effectiveness and safety of medications is discussed. The session also touches on how individual characteristics can affect drug responses, underscoring the need for personalized medicine and precise dosage adjustments.

Takeaways

• 😀 Pharmacokinetics studies how the concentration of a drug and its metabolites change in the body over time.
• 😀 The four key processes in pharmacokinetics are Absorption, Distribution, Metabolism, and Excretion (ADME).
• 😀 Absorption refers to the movement of a drug from its administration site into the bloodstream, usually through passive diffusion.
• 😀 Distribution is the process of drug transport throughout the body, from the bloodstream to various tissues and organs.
• 😀 Metabolism involves chemical changes to the drug in the body, often simplifying the molecule into metabolites for excretion.
• 😀 Excretion is the removal of the drug or its metabolites from the body, primarily through the kidneys.
• 😀 Pharmacokinetics is crucial for drug development, helping to optimize formulations and dosages for both humans and animals.
• 😀 Therapeutic Drug Monitoring (TDM) is used to personalize drug dosages, ensuring they are safe and effective for individual patients.
• 😀 Drugs with a narrow therapeutic index require careful monitoring to avoid toxicity or suboptimal therapeutic effects.
• 😀 Drug interactions, whether between drugs or with food, must be considered to prevent adverse effects and ensure treatment efficacy.
• 😀 Understanding pharmacokinetics helps design optimal drug delivery methods, like determining the best route of administration for each drug.

Q & A

What is pharmacokinetics?

Pharmacokinetics is the study of the changes in the concentration of drugs and their metabolites in the body over time. It focuses on the processes of absorption, distribution, metabolism, and excretion (ADME).

What does the acronym 'ADM' stand for in pharmacokinetics?

ADM stands for Absorption, Distribution, Metabolism, and Excretion. These are the key processes involved in the movement and transformation of drugs within the body.

What is absorption in the context of pharmacokinetics?

Absorption is the process by which a drug moves from the site of administration into the systemic circulation. It typically occurs through passive diffusion.

How does the pH of the absorption site influence drug absorption?

The pH of the absorption site can affect the ionization of the drug. A drug needs to be in its non-ionized form to pass through cell membranes more easily. The pH influences whether the drug remains ionized or not.

What role does cytochrome P450 play in metabolism?

Cytochrome P450 is an enzyme responsible for the majority of drug metabolism in the human body. It helps convert complex drugs into simpler metabolites, which can then be more easily excreted.

What is the primary organ responsible for excretion of drugs?

The kidneys are the primary organs responsible for the excretion of drugs and their metabolites, although other organs like the liver and salivary glands also contribute.

Why is pharmacokinetics important in drug development?

Pharmacokinetics is crucial in drug development because it helps determine the optimal drug dose, formulation, and delivery method, ensuring the drug's effectiveness and safety.

What is Therapeutic Drug Monitoring (TDM)?

Therapeutic Drug Monitoring (TDM) is the practice of measuring drug levels in the blood to ensure that the concentration remains within the therapeutic range, maximizing efficacy while minimizing toxicity.

What are some factors that can lead to drug-drug interactions?

Drug-drug interactions can occur when drugs alter each other's absorption, metabolism, or excretion. These interactions can either increase the risk of toxicity or reduce the effectiveness of a drug.

What is the Therapeutic Range and how does it relate to drug dosing?

The therapeutic range is the concentration of a drug in the blood that achieves the desired effect without causing toxicity. Dosing must be adjusted to ensure that drug levels remain within this range for effective treatment.