Types of Drugs

• Pharmaceuticals
• Recreational drugs
• Over-the-counter drugs
• Natural remedies
• Herbal medicines

Drug Classifications

• Analgesics
• Antibiotics
• Antidepressants
• Antihistamines
• Antipyretics

Drug Development Process

1. Discovery

2. Preclinical studies

3. Clinical trials

4. Approval

5. Post-marketing surveillance

Drug Discovery

• Identification of drug targets
• Lead compound identification
• Lead optimization
• Structure-activity relationship studies

Preclinical Studies

• In vitro studies
• In vivo studies
• Toxicity testing
• Pharmacokinetics
• Formulation development

Clinical Trials

• Phase 1: Safety and dosage
• Phase 2: Effectiveness and side effects
• Phase 3: Large-scale testing
• Phase 4: Post-approval monitoring

Approval Process

• Regulatory authorities
• Evaluating safety and efficacy
• Labeling and package insert requirements
• Drug scheduling and control measures

Post-marketing Surveillance

• Adverse drug reaction monitoring
• Pharmacovigilance
• Risk assessment and management
• Labeling updates and warnings

Examples of Drug Development

• Aspirin: Synthesis and uses
• Paracetamol: Structure and mechanism of action
• Penicillin: Discovery and production
• Prozac: Development and side effects
• Cannabis: Medicinal properties and controversies

Aspirin - Synthesis and Uses

• Acetylsalicylic acid
• Reaction between salicylic acid and acetic anhydride
• Uses: pain relief, reducing inflammation, preventing blood clots

Paracetamol - Structure and Mechanism of Action

• Chemical name: N-acetyl-para-aminophenol
• Analgesic and antipyretic properties
• Mechanism of action: inhibition of prostaglandin synthesis

Penicillin - Discovery and Production

• Discovery by Alexander Fleming
• Natural production by Penicillium fungi
• Commercial production through fermentation
• Importance in treating bacterial infections

Prozac - Development and Side Effects

• Fluoxetine hydrochloride
• Selective serotonin reuptake inhibitor (SSRI)
• Used for treating depression and anxiety disorders
• Side effects: nausea, insomnia, sexual dysfunction

Cannabis - Medicinal Properties and Controversies

• Chemical compounds: THC and CBD
• Medicinal properties: pain relief, appetite stimulation, muscle relaxation
• Controversies surrounding its legalization and use as a recreational drug

Principles of Chemical Equilibrium

• Definition of chemical equilibrium
• Equilibrium constant (Kc)
• Le Chatelier’s principle
• Factors affecting equilibrium

Equilibrium Constant Expression

• General form: aA + bB ⇌ cC + dD
• Expression: Kc = [C]^c[D]^d / [A]^a[B]^b
• Relationship between Kc and the balanced chemical equation

Le Chatelier’s Principle

• Reacting system’s response to change
• Shift in equilibrium position
• Examples of common disturbances and their effects on equilibrium

Factors Affecting Equilibrium

• Temperature change
• Pressure/volume change
• Concentration change
• Catalyst presence

Applications of Equilibrium in Real Life

• Haber process: Production of ammonia
• Solubility equilibrium: Precipitation and dissolution reactions
• Acid-base equilibrium: Buffer systems
• Industrial applications of equilibrium reactions

Equilibrium Constants and Reaction Quotients

• Relationship between equilibrium constants and reaction quotients
• Qc and Kc expressions
• Calculating Qc and comparing it to Kc to determine the direction of the reaction
• Examples of calculating equilibrium constants and reaction quotients

Equilibrium Constants and Temperature

• Effect of temperature on equilibrium constants
• Exothermic and endothermic reactions
• Le Chatelier’s principle and temperature changes
• The relationship between equilibrium constants and temperature using Van’t Hoff equation

Changes to Equilibrium: Concentration and Pressure

• Effect of concentration changes on equilibrium position
• Le Chatelier’s principle and concentration changes
• Effect of pressure changes on equilibrium position (for gases)
• Relationship between pressure and volume using the ideal gas law equation

Equilibrium in Acid-Base Systems

• Acid dissociation constant (Ka) and base dissociation constant (Kb)
• Relationship between Ka and Kb using the ionization constant for water (Kw)
• Calculating pH and pOH using equilibrium constants
• Acidic, basic, and neutral solutions

Common Ion Effect

• Effect of the presence of a common ion on solubility equilibrium
• Shift in equilibrium position due to the Le Chatelier’s principle
• Calculating the solubility of a sparingly soluble salt in the presence of a common ion

Acid-Base Titrations

• Definition and purpose of titrations
• Acid-base titrations and neutralization reactions
• Calculation of concentrations and volumes in titration reactions using balanced equations
• Examples of acid-base titrations and their applications

Redox Reactions

• Definition and examples of redox reactions
• Oxidation and reduction half-reactions
• Balancing redox equations using the half-reaction method
• Electrochemical cell notation and standard electrode potentials

Electrochemical Cells

• Galvanic cells and electrolytic cells
• Redox reactions and electron transfer
• Cell potential and cell voltage
• Nernst equation and its role in calculating cell potential

Faraday’s Laws of Electrolysis

• Faraday’s first law: relationship between the quantity of substance produced/deposited and the quantity of electric charge
• Faraday’s second law: relationship between the quantities of different substances produced/deposited and the quantities of electric charge
• Industrial applications of electrolysis

Nuclear Chemistry

• Radioactivity and radioactive decay
• Types of radioactive decay: alpha decay, beta decay, gamma decay
• Balancing nuclear equations
• Half-life and its role in radioactive decay and radiometric dating

Note to presenter: This concludes the lecture on chemistry for the 12th Boards exam. Ensure students have understood the presented material and answer any questions they may have.