Lebanon Pharmacy Colloquium cheat sheet

Bioavailability F = (AUC_oral / AUC_IV) × (Dose_IV / Dose_oral); for a simple one-compartment model, absolute F can also be estimated from cumulative urinary excretion ratios.

Biopharmaceutics Classification System: Class I high solubility/high permeability, II low solubility/high permeability, III high solubility/low permeability, IV low solubility/low permeability; Class I compounds are eligible for biowaivers of in vivo bioequivalence studies.

Noyes–Whitney dissolution rate: dm/dt = (D·A/h)·(Cs − C), so micronization or salt formation raises dissolution by increasing surface area A or solubility Cs.

Higuchi square-root model for matrix diffusion: Q = kH·t^0.5; zero-order release follows Q = k0·t; first-order release follows ln(remaining) = −k·t.

Stokes' law: v = d²(ρp − ρm)g / 18η; sedimentation velocity rises with the square of particle diameter and falls with vehicle viscosity.

The Nernst partition coefficient log P = log([solute]_octanol / [solute]_water) predicts passive transcellular permeability; log D is the pH-adjusted value for ionizable drugs.

Sterility assurance level 10⁻⁶ requires an overkill approach: F0 = Σ Δt · 10^((T − 121)/z), with z = 10 °C for moist heat; F0 ≥ 12 min is typical for terminally sterilized aqueous products.

Tablet compaction follows the Heckel equation ln(1/(1 − D)) = K·P + A, where the slope K relates inversely to the yield pressure of the material.

Competitive antagonists shift the log dose–response curve rightward without lowering Emax; non-competitive antagonists reduce Emax; the dose ratio minus 1 gives the Schild plot slope for pA2 estimation.

Henderson–Hasselbalch: for a weak acid, fraction ionized = 1/(1 + 10^(pKa − pH)); for a weak base, fraction ionized = 1/(1 + 10^(pH − pKa)).

Clearance CL = Dose/AUC = k·Vd; half-life t½ = 0.693·Vd/CL; steady-state concentration Css = (F·Dose/τ)/CL.

Loading dose = (Vd × target concentration)/F; maintenance dose rate = CL × target concentration/F.

Therapeutic index = TD50/ED50; a narrow index (e.g., digoxin, warfarin, lithium, phenytoin) mandates therapeutic drug monitoring.

Autonomic receptor mapping: M2 mediates cardiac vagal slowing; β1 mediates cardiac rate/contractility; β2 mediates bronchial and uterine relaxation; α1 mediates vasoconstriction.

Cytochrome P450 interactions: CYP3A4 inhibitors (ketoconazole, clarithromycin, grapefruit) raise levels of statins and tacrolimus; inducers (rifampicin, carbamazepine, St John's wort) lower them.

Opioid analgesia acts at μ receptors; naloxone reverses toxicity; the ceiling effect of buprenorphine reflects partial μ agonism.

Lipinski's Rule of Five: MW ≤ 500, log P ≤ 5, H-bond donors ≤ 5, H-bond acceptors ≤ 10; violation of two or more criteria predicts poor oral absorption.

Veber rules: rotatable bonds ≤ 10 and polar surface area ≤ 140 Ų predict good oral bioavailability.

pKa of a carboxylic acid is lowered by electron-withdrawing groups (e.g., α-fluorination) and raised by electron-donating groups; this governs ionization and absorption.

Prodrug design: esterification of a carboxyl or hydroxyl masks polarity to improve absorption; hydrolysis by esterases releases the active drug (e.g., enalapril → enalaprilat).

Bioisosteric replacement: –OH ↔ –NH2, –COOH ↔ tetrazole, –O– ↔ –S–, –CH3 ↔ –Cl, preserving steric and electronic properties while altering metabolism or pKa.

Chirality: enantiomers differ in receptor affinity; S-warfarin is 3–5× more potent than R-warfarin, and S-omeprazole (esomeprazole) is the active CYP2C19 substrate.

Phase I metabolism (CYP oxidation, reduction, hydrolysis) introduces or exposes functional groups; Phase II conjugation (glucuronidation, sulfation, acetylation, glutathione) increases water solubility for excretion.

QSAR and Hansch analysis relate log(1/C) to lipophilicity (π), electronic (σ) and steric (Es) parameters; the parabolic model identifies an optimum log P for activity.

Alkaloid classes: tropane (atropine, scopolamine from Atropa belladonna), indole (reserpine from Rauwolfia, vincristine from Catharanthus roseus), isoquinoline (morphine from Papaver somniferum), purine (caffeine).

Cardiac glycosides (Digitalis purpurea, D. lanata, Strophanthus) contain a steroid nucleus, a lactone ring, and a sugar moiety; they inhibit Na⁺/K⁺-ATPase.

Saponins are steroid or triterpenoid glycosides that form persistent foams in water and hemolyze red blood cells; ginsenosides are triterpenoid examples.

Flavonoids (quercetin, rutin) are polyphenolic C6–C3–C6 compounds with antioxidant activity; anthraquinones (senna, aloe) act as stimulant laxatives.

Essential oils are volatile terpenoid mixtures obtained by hydrodistillation or steam distillation (e.g., menthol from Mentha, eugenol from clove, thymol from thyme).

Standardization of herbal extracts uses marker compounds (e.g., hypericin/hyperforin in St John's wort, silymarin in milk thistle); the marker is not always the active constituent.

Plant identification methods: macroscopic and microscopic examination, organoleptic testing, thin-layer chromatography fingerprinting, and DNA barcoding.

Toxicity of natural products: pyrrolizidine alkaloids (Senecio, comfrey) cause hepatic veno-occlusive disease; aristolochic acid is nephrotoxic and carcinogenic.

Pharmacy practice in Lebanon is governed by the Ministry of Public Health (MoPH) and the Lebanese Order of Pharmacists (LOP); registration with the LOP is required to practice.

The LOP regulates licensure, professional discipline, and continuing education; only registered pharmacists may own or manage a community pharmacy.

Narcotic and psychotropic drugs are subject to special MoPH authorization, official prescription forms, and strict record-keeping with periodic inventory reconciliation.

Prescription requirements: prescriber identification, patient name, drug name, strength, dosage form, quantity, directions, and signature; controlled substances require additional documentation.

Pharmacists have a legal duty to verify prescriptions, refuse dispensing when forgery or therapeutic danger is evident, and report adverse drug reactions to the national pharmacovigilance program.

Generic substitution is permitted when the prescriber has not prohibited it and the substitute is bioequivalent and registered with the MoPH.

Ethical principles: beneficence, non-maleficence, autonomy (informed consent), confidentiality, and justice; conflicts of interest and kickbacks from prescribers are prohibited.

Record retention: prescription and controlled-drug records must be retained for the period specified by MoPH regulation and made available for inspection.

Pharmaceutical care process: assessment, care plan, evaluation, and follow-up; the pharmacist is accountable for the patient's drug-related needs.

Drug-related problems categories: indication (unnecessary, needs additional therapy), effectiveness (wrong drug, dose too low), safety (adverse reaction, dose too high), and adherence.

Counseling model: open-ended questions, teach-back verification, written instructions, and a schedule for follow-up; address the five rights of administration.

Therapeutic drug monitoring indications: narrow therapeutic index, known pharmacokinetic variability, suspected toxicity, and confirmation of efficacy (e.g., vancomycin, aminoglycosides, digoxin, lithium).

Anticoagulation counseling: warfarin requires INR monitoring (target 2–3 for most indications); direct oral anticoagulants require renal function and adherence review.

Asthma/COPD counseling: demonstrate inhaler technique, spacer use, rinse after inhaled corticosteroids, and distinguish reliever from controller therapy.

Diabetes counseling: recognize hypoglycemia symptoms, teach self-monitoring, review injection-site rotation, and explain sick-day rules for insulin and metformin.

Medication reconciliation at transitions of care reduces discrepancies; obtain the best possible medication history including over-the-counter and herbal products.

Inventory control: economic order quantity EOQ = √(2DS/H), where D is annual demand, S is order cost, H is holding cost per unit per year.

ABC analysis classifies stock by value (A items = high value, tight control); VED analysis classifies by criticality (vital, essential, desirable).

Pharmacoeconomic analyses: cost-minimization (equal outcomes), cost-effectiveness (cost per natural unit, e.g., cost per life-year gained), cost-utility (cost per QALY), cost-benefit (monetary outcomes).

Incremental cost-effectiveness ratio ICER = (C1 − C2)/(E1 − E2); compare against a willingness-to-pay threshold.

Dispensing verification: check the prescription against the dispensed product (drug, strength, form, quantity), label directions, and patient identity before release.

Good storage practices: monitor temperature and humidity, apply cold-chain (2–8 °C) for vaccines and insulin, and quarantine expired or recalled stock.

Purchasing and procurement: competitive tender, supplier qualification, batch documentation, and reconciliation of received goods against the purchase order.

Key performance indicators: inventory turnover = cost of goods sold/average inventory; gross margin and stock-out rate measure operational efficiency.

Poisoning management sequence: stabilize airway, breathing, circulation; identify the toxin; decontaminate (activated charcoal 1 g/kg within 1 h if airway is protected); give antidote; enhance elimination.

Antidote pairs: paracetamol → N-acetylcysteine; opioid → naloxone; benzodiazepine → flumazenil (caution in seizure risk); organophosphate → atropine plus pralidoxime; methanol/ethylene glycol → fomepizole or ethanol.

Paracetamol toxicity: the Rumack–Matthew nomogram guides NAC treatment based on the 4-hour serum level; hepatic injury results from NAPQI accumulation.

Adverse drug reaction classification: Type A (dose-dependent, predictable), Type B (idiosyncratic, unpredictable), Type C (chronic), Type D (delayed), Type E (end of use), Type F (failure of therapy).

Serotonin syndrome vs neuroleptic malignant syndrome: serotonin syndrome has clonus and hyperreflexia; NMS has rigidity, bradyreflexia, and elevated creatine kinase.

Anaphylaxis: intramuscular adrenaline 0.5 mg (1:1000) into the anterolateral thigh, repeated every 5 minutes as needed; adjuncts include oxygen, fluids, and antihistamines.

Therapeutic index and dose–response: a steep dose–response curve and narrow therapeutic index increase overdose risk (e.g., digoxin, lithium, theophylline).

Reporting: serious and unexpected adverse reactions must be reported to the national pharmacovigilance center; causality is assessed with the WHO-UMC or Naranjo scale.

Incidence = new cases/population at risk per time; prevalence = all existing cases/total population at a point or period; prevalence ≈ incidence × duration for stable disease.

Relative risk RR = incidence in exposed/incidence in unexposed (cohort studies); odds ratio OR = (a·d)/(b·c) approximates RR for rare outcomes in case-control studies.

Attributable risk = incidence in exposed − incidence in unexposed; population attributable fraction = (prevalence of exposure × (RR − 1))/(1 + prevalence of exposure × (RR − 1)).

Sensitivity = TP/(TP + FN); specificity = TN/(TN + FP); positive predictive value depends on prevalence and equals TP/(TP + FP).

Study designs: randomized controlled trial (causal inference), cohort (incidence, multiple outcomes), case-control (rare outcomes), cross-sectional (prevalence), ecological (group-level).

Bias types: selection, information/recall, confounding, and publication bias; randomization and blinding reduce confounding and information bias.

Pharmacovigilance signal detection uses spontaneous reporting, disproportionality measures (PRR, ROR), and periodic safety update reports submitted to regulators.

Vaccine safety and herd immunity: herd immunity threshold = 1 − 1/R0; for measles R0 ≈ 12–18, requiring roughly 92–95% coverage.

Bioavailability F = (AUC_oral / AUC_IV) × (Dose_IV / Dose_oral); for a simple one-compartment model, absolute F can also be estimated from cumulative urinary excretion ratios.

Biopharmaceutics Classification System: Class I high solubility/high permeability, II low solubility/high permeability, III high solubility/low permeability, IV low solubility/low permeability; Class I compounds are eligible for biowaivers of in vivo bioequivalence studies.

Noyes–Whitney dissolution rate: dm/dt = (D·A/h)·(Cs − C), so micronization or salt formation raises dissolution by increasing surface area A or solubility Cs.

Higuchi square-root model for matrix diffusion: Q = kH·t^0.5; zero-order release follows Q = k0·t; first-order release follows ln(remaining) = −k·t.

Stokes' law: v = d²(ρp − ρm)g / 18η; sedimentation velocity rises with the square of particle diameter and falls with vehicle viscosity.

The Nernst partition coefficient log P = log([solute]_octanol / [solute]_water) predicts passive transcellular permeability; log D is the pH-adjusted value for ionizable drugs.

Sterility assurance level 10⁻⁶ requires an overkill approach: F0 = Σ Δt · 10^((T − 121)/z), with z = 10 °C for moist heat; F0 ≥ 12 min is typical for terminally sterilized aqueous products.

Tablet compaction follows the Heckel equation ln(1/(1 − D)) = K·P + A, where the slope K relates inversely to the yield pressure of the material.

Competitive antagonists shift the log dose–response curve rightward without lowering Emax; non-competitive antagonists reduce Emax; the dose ratio minus 1 gives the Schild plot slope for pA2 estimation.

Henderson–Hasselbalch: for a weak acid, fraction ionized = 1/(1 + 10^(pKa − pH)); for a weak base, fraction ionized = 1/(1 + 10^(pH − pKa)).

Clearance CL = Dose/AUC = k·Vd; half-life t½ = 0.693·Vd/CL; steady-state concentration Css = (F·Dose/τ)/CL.

Loading dose = (Vd × target concentration)/F; maintenance dose rate = CL × target concentration/F.

Therapeutic index = TD50/ED50; a narrow index (e.g., digoxin, warfarin, lithium, phenytoin) mandates therapeutic drug monitoring.

Autonomic receptor mapping: M2 mediates cardiac vagal slowing; β1 mediates cardiac rate/contractility; β2 mediates bronchial and uterine relaxation; α1 mediates vasoconstriction.

Cytochrome P450 interactions: CYP3A4 inhibitors (ketoconazole, clarithromycin, grapefruit) raise levels of statins and tacrolimus; inducers (rifampicin, carbamazepine, St John's wort) lower them.

Opioid analgesia acts at μ receptors; naloxone reverses toxicity; the ceiling effect of buprenorphine reflects partial μ agonism.

Lipinski's Rule of Five: MW ≤ 500, log P ≤ 5, H-bond donors ≤ 5, H-bond acceptors ≤ 10; violation of two or more criteria predicts poor oral absorption.

Veber rules: rotatable bonds ≤ 10 and polar surface area ≤ 140 Ų predict good oral bioavailability.

pKa of a carboxylic acid is lowered by electron-withdrawing groups (e.g., α-fluorination) and raised by electron-donating groups; this governs ionization and absorption.

Prodrug design: esterification of a carboxyl or hydroxyl masks polarity to improve absorption; hydrolysis by esterases releases the active drug (e.g., enalapril → enalaprilat).

Bioisosteric replacement: –OH ↔ –NH2, –COOH ↔ tetrazole, –O– ↔ –S–, –CH3 ↔ –Cl, preserving steric and electronic properties while altering metabolism or pKa.

Chirality: enantiomers differ in receptor affinity; S-warfarin is 3–5× more potent than R-warfarin, and S-omeprazole (esomeprazole) is the active CYP2C19 substrate.

Phase I metabolism (CYP oxidation, reduction, hydrolysis) introduces or exposes functional groups; Phase II conjugation (glucuronidation, sulfation, acetylation, glutathione) increases water solubility for excretion.

QSAR and Hansch analysis relate log(1/C) to lipophilicity (π), electronic (σ) and steric (Es) parameters; the parabolic model identifies an optimum log P for activity.

Alkaloid classes: tropane (atropine, scopolamine from Atropa belladonna), indole (reserpine from Rauwolfia, vincristine from Catharanthus roseus), isoquinoline (morphine from Papaver somniferum), purine (caffeine).

Cardiac glycosides (Digitalis purpurea, D. lanata, Strophanthus) contain a steroid nucleus, a lactone ring, and a sugar moiety; they inhibit Na⁺/K⁺-ATPase.

Saponins are steroid or triterpenoid glycosides that form persistent foams in water and hemolyze red blood cells; ginsenosides are triterpenoid examples.

Flavonoids (quercetin, rutin) are polyphenolic C6–C3–C6 compounds with antioxidant activity; anthraquinones (senna, aloe) act as stimulant laxatives.

Essential oils are volatile terpenoid mixtures obtained by hydrodistillation or steam distillation (e.g., menthol from Mentha, eugenol from clove, thymol from thyme).

Standardization of herbal extracts uses marker compounds (e.g., hypericin/hyperforin in St John's wort, silymarin in milk thistle); the marker is not always the active constituent.

Plant identification methods: macroscopic and microscopic examination, organoleptic testing, thin-layer chromatography fingerprinting, and DNA barcoding.

Toxicity of natural products: pyrrolizidine alkaloids (Senecio, comfrey) cause hepatic veno-occlusive disease; aristolochic acid is nephrotoxic and carcinogenic.

Pharmacy practice in Lebanon is governed by the Ministry of Public Health (MoPH) and the Lebanese Order of Pharmacists (LOP); registration with the LOP is required to practice.

The LOP regulates licensure, professional discipline, and continuing education; only registered pharmacists may own or manage a community pharmacy.

Narcotic and psychotropic drugs are subject to special MoPH authorization, official prescription forms, and strict record-keeping with periodic inventory reconciliation.

Prescription requirements: prescriber identification, patient name, drug name, strength, dosage form, quantity, directions, and signature; controlled substances require additional documentation.

Pharmacists have a legal duty to verify prescriptions, refuse dispensing when forgery or therapeutic danger is evident, and report adverse drug reactions to the national pharmacovigilance program.

Generic substitution is permitted when the prescriber has not prohibited it and the substitute is bioequivalent and registered with the MoPH.

Ethical principles: beneficence, non-maleficence, autonomy (informed consent), confidentiality, and justice; conflicts of interest and kickbacks from prescribers are prohibited.

Record retention: prescription and controlled-drug records must be retained for the period specified by MoPH regulation and made available for inspection.

Pharmaceutical care process: assessment, care plan, evaluation, and follow-up; the pharmacist is accountable for the patient's drug-related needs.

Drug-related problems categories: indication (unnecessary, needs additional therapy), effectiveness (wrong drug, dose too low), safety (adverse reaction, dose too high), and adherence.

Counseling model: open-ended questions, teach-back verification, written instructions, and a schedule for follow-up; address the five rights of administration.

Therapeutic drug monitoring indications: narrow therapeutic index, known pharmacokinetic variability, suspected toxicity, and confirmation of efficacy (e.g., vancomycin, aminoglycosides, digoxin, lithium).

Anticoagulation counseling: warfarin requires INR monitoring (target 2–3 for most indications); direct oral anticoagulants require renal function and adherence review.

Asthma/COPD counseling: demonstrate inhaler technique, spacer use, rinse after inhaled corticosteroids, and distinguish reliever from controller therapy.

Diabetes counseling: recognize hypoglycemia symptoms, teach self-monitoring, review injection-site rotation, and explain sick-day rules for insulin and metformin.

Medication reconciliation at transitions of care reduces discrepancies; obtain the best possible medication history including over-the-counter and herbal products.

Inventory control: economic order quantity EOQ = √(2DS/H), where D is annual demand, S is order cost, H is holding cost per unit per year.

ABC analysis classifies stock by value (A items = high value, tight control); VED analysis classifies by criticality (vital, essential, desirable).

Pharmacoeconomic analyses: cost-minimization (equal outcomes), cost-effectiveness (cost per natural unit, e.g., cost per life-year gained), cost-utility (cost per QALY), cost-benefit (monetary outcomes).

Incremental cost-effectiveness ratio ICER = (C1 − C2)/(E1 − E2); compare against a willingness-to-pay threshold.

Dispensing verification: check the prescription against the dispensed product (drug, strength, form, quantity), label directions, and patient identity before release.

Good storage practices: monitor temperature and humidity, apply cold-chain (2–8 °C) for vaccines and insulin, and quarantine expired or recalled stock.

Purchasing and procurement: competitive tender, supplier qualification, batch documentation, and reconciliation of received goods against the purchase order.

Key performance indicators: inventory turnover = cost of goods sold/average inventory; gross margin and stock-out rate measure operational efficiency.

Poisoning management sequence: stabilize airway, breathing, circulation; identify the toxin; decontaminate (activated charcoal 1 g/kg within 1 h if airway is protected); give antidote; enhance elimination.

Antidote pairs: paracetamol → N-acetylcysteine; opioid → naloxone; benzodiazepine → flumazenil (caution in seizure risk); organophosphate → atropine plus pralidoxime; methanol/ethylene glycol → fomepizole or ethanol.

Paracetamol toxicity: the Rumack–Matthew nomogram guides NAC treatment based on the 4-hour serum level; hepatic injury results from NAPQI accumulation.

Adverse drug reaction classification: Type A (dose-dependent, predictable), Type B (idiosyncratic, unpredictable), Type C (chronic), Type D (delayed), Type E (end of use), Type F (failure of therapy).

Serotonin syndrome vs neuroleptic malignant syndrome: serotonin syndrome has clonus and hyperreflexia; NMS has rigidity, bradyreflexia, and elevated creatine kinase.

Anaphylaxis: intramuscular adrenaline 0.5 mg (1:1000) into the anterolateral thigh, repeated every 5 minutes as needed; adjuncts include oxygen, fluids, and antihistamines.

Therapeutic index and dose–response: a steep dose–response curve and narrow therapeutic index increase overdose risk (e.g., digoxin, lithium, theophylline).

Reporting: serious and unexpected adverse reactions must be reported to the national pharmacovigilance center; causality is assessed with the WHO-UMC or Naranjo scale.

Incidence = new cases/population at risk per time; prevalence = all existing cases/total population at a point or period; prevalence ≈ incidence × duration for stable disease.

Relative risk RR = incidence in exposed/incidence in unexposed (cohort studies); odds ratio OR = (a·d)/(b·c) approximates RR for rare outcomes in case-control studies.

Attributable risk = incidence in exposed − incidence in unexposed; population attributable fraction = (prevalence of exposure × (RR − 1))/(1 + prevalence of exposure × (RR − 1)).

Sensitivity = TP/(TP + FN); specificity = TN/(TN + FP); positive predictive value depends on prevalence and equals TP/(TP + FP).

Study designs: randomized controlled trial (causal inference), cohort (incidence, multiple outcomes), case-control (rare outcomes), cross-sectional (prevalence), ecological (group-level).

Bias types: selection, information/recall, confounding, and publication bias; randomization and blinding reduce confounding and information bias.

Pharmacovigilance signal detection uses spontaneous reporting, disproportionality measures (PRR, ROR), and periodic safety update reports submitted to regulators.

Vaccine safety and herd immunity: herd immunity threshold = 1 − 1/R0; for measles R0 ≈ 12–18, requiring roughly 92–95% coverage.

Bioavailability F = (AUC_oral / AUC_IV) × (Dose_IV / Dose_oral); for a simple one-compartment model, absolute F can also be estimated from cumulative urinary excretion ratios.

Biopharmaceutics Classification System: Class I high solubility/high permeability, II low solubility/high permeability, III high solubility/low permeability, IV low solubility/low permeability; Class I compounds are eligible for biowaivers of in vivo bioequivalence studies.

Noyes–Whitney dissolution rate: dm/dt = (D·A/h)·(Cs − C), so micronization or salt formation raises dissolution by increasing surface area A or solubility Cs.

Higuchi square-root model for matrix diffusion: Q = kH·t^0.5; zero-order release follows Q = k0·t; first-order release follows ln(remaining) = −k·t.

Stokes' law: v = d²(ρp − ρm)g / 18η; sedimentation velocity rises with the square of particle diameter and falls with vehicle viscosity.

The Nernst partition coefficient log P = log([solute]_octanol / [solute]_water) predicts passive transcellular permeability; log D is the pH-adjusted value for ionizable drugs.

Sterility assurance level 10⁻⁶ requires an overkill approach: F0 = Σ Δt · 10^((T − 121)/z), with z = 10 °C for moist heat; F0 ≥ 12 min is typical for terminally sterilized aqueous products.

Tablet compaction follows the Heckel equation ln(1/(1 − D)) = K·P + A, where the slope K relates inversely to the yield pressure of the material.

Competitive antagonists shift the log dose–response curve rightward without lowering Emax; non-competitive antagonists reduce Emax; the dose ratio minus 1 gives the Schild plot slope for pA2 estimation.

Henderson–Hasselbalch: for a weak acid, fraction ionized = 1/(1 + 10^(pKa − pH)); for a weak base, fraction ionized = 1/(1 + 10^(pH − pKa)).

Clearance CL = Dose/AUC = k·Vd; half-life t½ = 0.693·Vd/CL; steady-state concentration Css = (F·Dose/τ)/CL.

Loading dose = (Vd × target concentration)/F; maintenance dose rate = CL × target concentration/F.

Therapeutic index = TD50/ED50; a narrow index (e.g., digoxin, warfarin, lithium, phenytoin) mandates therapeutic drug monitoring.

Autonomic receptor mapping: M2 mediates cardiac vagal slowing; β1 mediates cardiac rate/contractility; β2 mediates bronchial and uterine relaxation; α1 mediates vasoconstriction.

Cytochrome P450 interactions: CYP3A4 inhibitors (ketoconazole, clarithromycin, grapefruit) raise levels of statins and tacrolimus; inducers (rifampicin, carbamazepine, St John's wort) lower them.

Opioid analgesia acts at μ receptors; naloxone reverses toxicity; the ceiling effect of buprenorphine reflects partial μ agonism.

Lipinski's Rule of Five: MW ≤ 500, log P ≤ 5, H-bond donors ≤ 5, H-bond acceptors ≤ 10; violation of two or more criteria predicts poor oral absorption.

Veber rules: rotatable bonds ≤ 10 and polar surface area ≤ 140 Ų predict good oral bioavailability.

pKa of a carboxylic acid is lowered by electron-withdrawing groups (e.g., α-fluorination) and raised by electron-donating groups; this governs ionization and absorption.

Prodrug design: esterification of a carboxyl or hydroxyl masks polarity to improve absorption; hydrolysis by esterases releases the active drug (e.g., enalapril → enalaprilat).

Bioisosteric replacement: –OH ↔ –NH2, –COOH ↔ tetrazole, –O– ↔ –S–, –CH3 ↔ –Cl, preserving steric and electronic properties while altering metabolism or pKa.

Chirality: enantiomers differ in receptor affinity; S-warfarin is 3–5× more potent than R-warfarin, and S-omeprazole (esomeprazole) is the active CYP2C19 substrate.

Phase I metabolism (CYP oxidation, reduction, hydrolysis) introduces or exposes functional groups; Phase II conjugation (glucuronidation, sulfation, acetylation, glutathione) increases water solubility for excretion.

QSAR and Hansch analysis relate log(1/C) to lipophilicity (π), electronic (σ) and steric (Es) parameters; the parabolic model identifies an optimum log P for activity.

Alkaloid classes: tropane (atropine, scopolamine from Atropa belladonna), indole (reserpine from Rauwolfia, vincristine from Catharanthus roseus), isoquinoline (morphine from Papaver somniferum), purine (caffeine).

Cardiac glycosides (Digitalis purpurea, D. lanata, Strophanthus) contain a steroid nucleus, a lactone ring, and a sugar moiety; they inhibit Na⁺/K⁺-ATPase.

Saponins are steroid or triterpenoid glycosides that form persistent foams in water and hemolyze red blood cells; ginsenosides are triterpenoid examples.

Flavonoids (quercetin, rutin) are polyphenolic C6–C3–C6 compounds with antioxidant activity; anthraquinones (senna, aloe) act as stimulant laxatives.

Essential oils are volatile terpenoid mixtures obtained by hydrodistillation or steam distillation (e.g., menthol from Mentha, eugenol from clove, thymol from thyme).

Standardization of herbal extracts uses marker compounds (e.g., hypericin/hyperforin in St John's wort, silymarin in milk thistle); the marker is not always the active constituent.

Plant identification methods: macroscopic and microscopic examination, organoleptic testing, thin-layer chromatography fingerprinting, and DNA barcoding.

Toxicity of natural products: pyrrolizidine alkaloids (Senecio, comfrey) cause hepatic veno-occlusive disease; aristolochic acid is nephrotoxic and carcinogenic.

Pharmacy practice in Lebanon is governed by the Ministry of Public Health (MoPH) and the Lebanese Order of Pharmacists (LOP); registration with the LOP is required to practice.

The LOP regulates licensure, professional discipline, and continuing education; only registered pharmacists may own or manage a community pharmacy.

Narcotic and psychotropic drugs are subject to special MoPH authorization, official prescription forms, and strict record-keeping with periodic inventory reconciliation.

Prescription requirements: prescriber identification, patient name, drug name, strength, dosage form, quantity, directions, and signature; controlled substances require additional documentation.

Pharmacists have a legal duty to verify prescriptions, refuse dispensing when forgery or therapeutic danger is evident, and report adverse drug reactions to the national pharmacovigilance program.

Generic substitution is permitted when the prescriber has not prohibited it and the substitute is bioequivalent and registered with the MoPH.

Ethical principles: beneficence, non-maleficence, autonomy (informed consent), confidentiality, and justice; conflicts of interest and kickbacks from prescribers are prohibited.

Record retention: prescription and controlled-drug records must be retained for the period specified by MoPH regulation and made available for inspection.

Pharmaceutical care process: assessment, care plan, evaluation, and follow-up; the pharmacist is accountable for the patient's drug-related needs.

Drug-related problems categories: indication (unnecessary, needs additional therapy), effectiveness (wrong drug, dose too low), safety (adverse reaction, dose too high), and adherence.

Counseling model: open-ended questions, teach-back verification, written instructions, and a schedule for follow-up; address the five rights of administration.

Therapeutic drug monitoring indications: narrow therapeutic index, known pharmacokinetic variability, suspected toxicity, and confirmation of efficacy (e.g., vancomycin, aminoglycosides, digoxin, lithium).

Anticoagulation counseling: warfarin requires INR monitoring (target 2–3 for most indications); direct oral anticoagulants require renal function and adherence review.

Asthma/COPD counseling: demonstrate inhaler technique, spacer use, rinse after inhaled corticosteroids, and distinguish reliever from controller therapy.

Diabetes counseling: recognize hypoglycemia symptoms, teach self-monitoring, review injection-site rotation, and explain sick-day rules for insulin and metformin.

Medication reconciliation at transitions of care reduces discrepancies; obtain the best possible medication history including over-the-counter and herbal products.

Inventory control: economic order quantity EOQ = √(2DS/H), where D is annual demand, S is order cost, H is holding cost per unit per year.

ABC analysis classifies stock by value (A items = high value, tight control); VED analysis classifies by criticality (vital, essential, desirable).

Pharmacoeconomic analyses: cost-minimization (equal outcomes), cost-effectiveness (cost per natural unit, e.g., cost per life-year gained), cost-utility (cost per QALY), cost-benefit (monetary outcomes).

Incremental cost-effectiveness ratio ICER = (C1 − C2)/(E1 − E2); compare against a willingness-to-pay threshold.

Dispensing verification: check the prescription against the dispensed product (drug, strength, form, quantity), label directions, and patient identity before release.

Good storage practices: monitor temperature and humidity, apply cold-chain (2–8 °C) for vaccines and insulin, and quarantine expired or recalled stock.

Purchasing and procurement: competitive tender, supplier qualification, batch documentation, and reconciliation of received goods against the purchase order.

Key performance indicators: inventory turnover = cost of goods sold/average inventory; gross margin and stock-out rate measure operational efficiency.

Poisoning management sequence: stabilize airway, breathing, circulation; identify the toxin; decontaminate (activated charcoal 1 g/kg within 1 h if airway is protected); give antidote; enhance elimination.

Antidote pairs: paracetamol → N-acetylcysteine; opioid → naloxone; benzodiazepine → flumazenil (caution in seizure risk); organophosphate → atropine plus pralidoxime; methanol/ethylene glycol → fomepizole or ethanol.

Paracetamol toxicity: the Rumack–Matthew nomogram guides NAC treatment based on the 4-hour serum level; hepatic injury results from NAPQI accumulation.

Adverse drug reaction classification: Type A (dose-dependent, predictable), Type B (idiosyncratic, unpredictable), Type C (chronic), Type D (delayed), Type E (end of use), Type F (failure of therapy).

Serotonin syndrome vs neuroleptic malignant syndrome: serotonin syndrome has clonus and hyperreflexia; NMS has rigidity, bradyreflexia, and elevated creatine kinase.

Anaphylaxis: intramuscular adrenaline 0.5 mg (1:1000) into the anterolateral thigh, repeated every 5 minutes as needed; adjuncts include oxygen, fluids, and antihistamines.

Therapeutic index and dose–response: a steep dose–response curve and narrow therapeutic index increase overdose risk (e.g., digoxin, lithium, theophylline).

Reporting: serious and unexpected adverse reactions must be reported to the national pharmacovigilance center; causality is assessed with the WHO-UMC or Naranjo scale.

Incidence = new cases/population at risk per time; prevalence = all existing cases/total population at a point or period; prevalence ≈ incidence × duration for stable disease.

Relative risk RR = incidence in exposed/incidence in unexposed (cohort studies); odds ratio OR = (a·d)/(b·c) approximates RR for rare outcomes in case-control studies.

Attributable risk = incidence in exposed − incidence in unexposed; population attributable fraction = (prevalence of exposure × (RR − 1))/(1 + prevalence of exposure × (RR − 1)).

Sensitivity = TP/(TP + FN); specificity = TN/(TN + FP); positive predictive value depends on prevalence and equals TP/(TP + FP).

Study designs: randomized controlled trial (causal inference), cohort (incidence, multiple outcomes), case-control (rare outcomes), cross-sectional (prevalence), ecological (group-level).

Bias types: selection, information/recall, confounding, and publication bias; randomization and blinding reduce confounding and information bias.

Pharmacovigilance signal detection uses spontaneous reporting, disproportionality measures (PRR, ROR), and periodic safety update reports submitted to regulators.

Vaccine safety and herd immunity: herd immunity threshold = 1 − 1/R0; for measles R0 ≈ 12–18, requiring roughly 92–95% coverage.