TOTAL

Passive Diffusion

Historical focus on physical chemical characteristics driving biological processes, emphasizing concentration gradients without energy.

Transport in Pharmacology

Interdependent processes like absorption, distribution, metabolism, and excretion (ADME), with absorption as the initial step.

Membrane Crossing and Diffusion

Lipophilic and polar membranes affecting drug absorption, with diffusion being transcellular or paracellular.

Challenges in Drug Development

Emphasis on drug lipophilicity for absorption, tissue-specific diffusion rates, and understanding membrane crossing complexities.

Blood Brain Barrier

Acts as a selective barrier for compounds, impacting drug effects on the central nervous system.

Ionization and pH

pH-dependent drug distribution, Henderson-Hasselbeck equation for concentration gradients, and pH's influence on drug behavior.

Protein Binding and Distribution

Impact on drug concentration, free drug concentration importance, and irreversible binding leading to toxicity.

ABC Transporters

Crucial in pharmacokinetics, named based on substrates, and overexpression in tumor cells leading to drug resistance.

Drug Metabolism Impact

Detoxification, bioactivation, and metabolism's role in drug activity and development.

Organ Specific Metabolism

Liver as the primary organ for drug metabolism, with varying enzyme profiles in different organs.

Alcohol Transferase Enzyme

An enzyme involved in the transfer of alcohol groups between molecules.

Acetylation

The process of adding an acetyl group to a compound, reducing its polarity by masking hydroxyl groups.

Drug Metabolism

The process by which drugs are chemically altered in the body, involving polymorphic and inducible enzymes.

Methylation

The addition of a methyl group to a compound, reducing its polarity and affecting solubility and drug activity.

Amino Acid Conjugation

Involves adding an amino acid to a compound, common in mitochondria for drug metabolism.

Transporters

Proteins that aid in eliminating metabolites from the body, recognizing polar compounds and aiding in excretion.

Genetic Polymorphisms

Variations in genes that can impact drug metabolism and effectiveness, screened by drug companies for broader efficacy.

Enzyme Induction

The slow process of increasing enzyme expression over time, affected by factors like daily medication intake and lifestyle choices.

Drug-Drug Interactions

Occur when one drug affects the metabolism of another, leading to changes in drug concentration without altering protein expression.

Glomerular Filtration Rate (GFR)

The total volume of filtrate produced by the nephron, impacting drug elimination and dosing based on individual kidney function.

Volume Distribution

Different concentrations indicate varying volume distributions based on drug characteristics.

Importance of Volume Distribution in Dosing

Understanding volume distribution is crucial for dosing accuracy and achieving target concentrations.

Apparent Volume

Theoretical volume distribution correlated with drug characteristics for accurate dosing.

Standardization of Volumes

Volumes standardized to 70 kilograms for adult body size for comparison in physiology literature.

Factors Affecting Volume Distribution

Factors like body size, lean body mass, and age influence volume distribution estimates for different drugs.

Enzymes and Cofactors

Enzymes and cofactors in high concentrations metabolize drugs, forming complexes for drug metabolism.

First-Order Kinetics

Concentration and elimination rate have a proportional relationship in first-order kinetics.

Zero-Order Kinetics

Rate of elimination becomes independent of concentration in zero-order kinetics.

Nonlinear Kinetics

Nonlinear kinetics involve V max and K M, affecting drug clearance pathways.

Bioavailability

Bioavailability represents the fraction of the dose reaching circulation intact, crucial for drug effectiveness.

Pharmacokinetic Studies

Studies focus on parameters like dose, Cmax, Tmax, and AUC for regulatory approval and reliability assessment.

Drug Interactions

Understanding pharmacokinetics is vital to predict and manage drug interactions for safe and effective medication use.

Enzyme Metabolism and Drug Interactions

Identifying metabolizing enzymes, studying transporter involvement, and predicting drug interactions are essential for medication safety.

Irreversible Inhibitors

Inhibitors like penicillin that permanently bind to their target enzymes, effectively and safely.

Drug Interactions

Interactions between drugs that are usually not utilized positively.

Cimetidine

A drug used to inhibit toxic metabolite formation and increase therapeutic range.

Reversible Inhibition

A strategy to temporarily inhibit enzymes to increase therapeutic range and improve patient outcomes.

Ritonavir

An inhibitor used to extend the half-life of drugs, exemplified during the COVID pandemic.

Pharmacokinetics

The study of drug absorption, distribution, metabolism, and excretion in the body.

Transporters

Proteins crucial for drug disposition in organs like the intestine, liver, kidney, and blood-brain barrier.

Enzyme Metabolism

Processes like CYP2D6 that affect drug metabolism and interactions.

Drug-Drug Interaction (DDI)

Assessment of potential interactions between drugs, enzymes, and transporters.

Controlled-Release Morphine

Careful control of morphine dosage to balance pain relief and avoid respiratory depression.