PK

Pharmacokinetics of Naproxen

Pharmacokinetics of Naproxen

In linear pharmacokinetics (PK), when we increase the dose (D) of the drug, its level in our body or systemic exposure (AUC) increases proportionally (red curve on left graph). What is our inference? This implies that both oral bioavailability (F) and clearance (CL) are constant such that dose (D) and ... Read More
Concepts of Elimination Rate and Clearance of Drugs

Concepts of Elimination Rate and Clearance of Drugs

Have we come across a presenter who commented that the ‘clearance rate of a drug is high or low’? A question arises: Is clearance an elimination rate of a given drug? Some of us remain unclear regarding the concepts of elimination rate and clearance of drugs. Elimination rate is the ... Read More
Relation Between Renal clearance and Urine pH

Relation Between Renal clearance and Urine pH

Do we know why the renal clearance of some drugs (e.g. memantine) is sensitive to the change in urine pH? Memantine is a medication taken to slow the progression of moderate-to-severe Alzheimer’s disease. It is a basic (alkaline) and lipophilic (fat-liking) drug (pKa 10 and logP 3). Once memantine is ... Read More
Volume of Distribution (V)

Volume of Distribution (V)

Do we know that one of the most misunderstood pharmacokinetic (PK) parameters is volume of distribution (V)? This is especially exacerbated by the many terminologies of V. Let’s start with a simple yet important understanding that V is a proportionality factor that relates the amount of drug in the body ... Read More
Introduction to Drug Action

Introduction to Drug Action

The action of a drug is believed to be due to the interaction of that drug with endogenous and exogenous substrate molecules found in the body. When one or more active drug molecules bind to the target endogenous and exogenous molecules, they cause a change or inhibit the biological activity ... Read More
Pharmacokinetic Service in Hospitals

Pharmacokinetic Service in Hospitals

Clinical pharmacokinetics is the tools that can be used to optimize pharmaceutical care services by determining the dosage regimens of specific drug products for specific patients to maximize pharmacotherapeutic effects and minimize toxic effects. A list of pharmacokinetic services are mentioned below: (1) Designing patient-specific Medication dosage regimens based on ... Read More