Clinical Pharmacology, Therapeutics, and Antimicrobial Stewardship

Comprehensive vocabulary flashcards reviewing core pharmacological concepts, pharmacokinetic and pharmacodynamic principles, local anaesthetics, antimicrobial classifications, prescribing standards, and toxicology.

Quality Use of Medicines (QUM)

The clinical practice of selecting management options wisely, choosing suitable medicines tailored to patient needs, and using medicines safely and effectively to achieve optimal health outcomes.

Standard for the Uniform Scheduling of Medicines and Poisons (SUSMP)

The national regulatory standard (Poison Standard) used in Australia for setting the rules and schedules for supplying and prescribing medicines, including Schedule 4 and Schedule 8 substances.

Duty of Candour

The ethical and professional requirement for health practitioners to maintain openness and transparency with patients and their families when unintended harm or adverse events occur.

Notifiable Conduct

Practitioner misconduct requiring mandatory notification to regulatory bodies, including practising under the influence of alcohol or drugs, engaging in sexual misconduct, placing the public at risk of harm due to an impairment, or departing significantly from accepted professional standards.

Lipinski's Rule of 5

A rule of thumb predicting optimal oral drug absorption: molecular weight $< 500\,\text{g/mol}$, fewer than $5$ hydrogen bond donors, fewer than $10$ hydrogen bond acceptors, and a $\text{Log } P < 5$.

Partition Coefficient

The ratio representing the differential solubility of a compound between a non-polar solvent and water, expressed as: $\text{Partition Coefficient} = \frac{\text{Concentration in the lipid phase}}{\text{Concentration in the aqueous phase}}$

Volume of Distribution ($V_{\text{DIST}}$; $V$)

The theoretical fluid volume into which the total administered dose of a drug would need to be distributed to achieve its observed blood plasma concentration, calculated as: $V = \frac{\text{DOSE (MG)}}{\text{Plasma concentration } \left(\frac{\text{mg}}{\text{L}}\right)}$

Bioavailability ($F$)

The fraction of an administered active drug dose that reaches the systemic circulation intact, calculated relative to intravenous dosing as: $F = \frac{\text{AUC}_{\text{Oral}}}{\text{AUC}_{\text{IV}}} \times \frac{\text{Dose}_{\text{IV}}}{\text{Dose}_{\text{Oral}}}$

First-Pass Metabolism

The pre-systemic metabolism and elimination of an orally administered drug occurring primarily in the gut wall and liver before it reaches systemic circulation.

First-Order Elimination Kinetics

A clearance process where a constant fraction or percentage of drug is removed per unit of time, causing the rate of elimination to decrease proportionally with falling plasma concentration.

Zero-Order Elimination Kinetics

A clearance process where a fixed, constant amount of drug is removed per unit of time regardless of blood concentration due to saturation of metabolic enzymes or clearance pathways.

Intrahepatic Recirculation

The reabsorption of biliary-excreted drugs back into the portal bloodstream following hydrolysis of drug glucuronide conjugates by intestinal bacterial enzymes, prolonging drug half-life.

Therapeutic Window

The range of plasma drug concentrations spanning between the Minimum Effective Concentration (MEC) and the Minimum Toxic Concentration (MTC) where efficacy is produced without toxicity.

Clearance ($CL$)

The volume of plasma completely cleared of a drug per unit of time, representing the body's overall efficiency in irreversibly eliminating a drug.

Receptor Affinity

The chemical tendency or binding strength of a ligand (drug) to bind to its specific receptor target.

Receptor Efficacy

The capacity of an agonist-receptor complex to initiate conformational changes and downstream signal transduction to produce a biological effect.

$$EC_{50}$$

The molar concentration of an agonist required to produce $50\%$ of its own maximal observable biological response, serving as an index of potency.

Competitive Reversible Antagonist

A ligand that reversibly binds the receptor active site without activating it, increasing the agonist's $EC_{50}$ (surmountable shift) without lowering the maximal possible response.

Irreversible Antagonist

A ligand that binds covalently or with extremely high affinity to a receptor, depressing the maximal possible response of the agonist without changing the agonist's $EC_{50}$.

Methemoglobinemia

A disorder caused by oxidation of ferrous iron ($\text{Fe}^{2+}$) to ferric iron ($\text{Fe}^{3+}$) in haemoglobin, impairing oxygen carriage and presenting clinically with slate-grey skin discolouration, cyanosis, and dark red/brown blood; an adverse effect associated with prilocaine.

Ideal Body Weight (IBW)

Calculated baseline body mass used for dosing local anaesthetics in obese patients, determined by: $\text{Male Wt (kg)} = 50 + 0.9 \times (\text{Height} - 152\,\text{cm})$ and $\text{Female Wt (kg)} = 45.5 + 0.9 \times (\text{Height} - 152\,\text{cm})$

I-GRAB

A clinical mnemonic for adverse effects associated with NSAIDs: Interactions with other medications (e.g. Warfarin), Gastric ulceration, Renal impairment, Asthma sensitivity, and Bleeding risk.

Triple Whammy

The concurrent administration of an NSAID, a diuretic, and an ACE inhibitor (or ARB), which severely impairs renal haemodynamics and sharply increases the risk of acute kidney injury.

Serotonin Syndrome

A potentially fatal toxic state caused by excessive CNS serotonergic agonism, characterized by neuromuscular excitability (hyperreflexia, clonus, tremors), autonomic instability, and altered mental status.

Naloxone

A pure competitive antagonist at mu, kappa, and sigma opioid receptors, indicated for rapid reversal of respiratory depression and sedation in acute opioid overdose.

Bactericidal Antibiotic

An antimicrobial agent that actively kills bacterial cells outright, producing a direct reduction in the total number of viable cells independently of host immune activity.

Bacteriostatic Antibiotic

An antimicrobial agent that arrests the growth and replication of bacteria without directly killing them, allowing the host immune system to eradicate remaining viable organisms.

Beta-Lactamases

Bacterial enzymes that hydrolyse the beta-lactam ring core of penicillins and cephalosporins, converting them into inactive metabolites and conferring antimicrobial resistance.

Clavulanic Acid

A beta-lactamase inhibitor that binds irreversibly to bacterial beta-lactamase enzymes, preventing enzymatic inactivation of co-administered aminopenicillins (such as amoxicillin).

Grey Baby Syndrome

A fatal neonatal toxicity syndrome caused by chloramphenicol accumulation due to deficient neonatal hepatic glucuronidation, presenting with cyanosis, pallor, and lethargy.

Empirical Antimicrobial Therapy

The clinical initiation of antimicrobial therapy targeted against the most likely causative pathogens before formal culture and susceptibility laboratory results are available.

Antimicrobial Stewardship (AMS)

An institutional healthcare strategy designed to optimise antimicrobial selection, dosing, route, and treatment duration to ensure clinical efficacy while limiting resistance and toxicity.

Mycoses

Diseases caused by fungal infection, categorised into four clinical classes: superficial, cutaneous (nail/hair), subcutaneous, and systemic infections.

Fingertip Unit (FTU)

The standard metric used to measure topical corticosteroid administration, defined as the amount of cream or ointment squeezed out of a standard nozzle from the adult distal interphalangeal crease to the fingertip (sufficient to cover two adult palms).

Calcineurin Inhibitors (CNIs)

Immunosuppressive drugs (e.g., cyclosporin, tacrolimus) that bind cytosolic immunophilins to block calcineurin phosphatase activity, halting NFAT dephosphorylation and repressing IL-2 gene transcription.

Type A Adverse Drug Reaction

A dose-dependent, pharmacologically predictable adverse drug effect with high morbidity, low mortality, and responsiveness to dose reduction (e.g., hypoglycaemia from insulin).

Type B Adverse Drug Reaction

An unpredictable, idiosyncratic or immune-mediated adverse drug reaction that is independent of therapeutic dosing, exhibiting high mortality and requiring immediate drug cessation.

Exposome

The cumulative measure of environmental, lifestyle, and social exposures an individual encounters throughout life, together with the corresponding biological responses.

Bioactivation-Dependent Toxicant

A parent xenobiotic that lacks intrinsic reactivity but is converted into an electrophilic, chemically reactive metabolite via endogenous metabolism (e.g., CYP450 pathways), leading to macromolecular adduct formation.