General Pharmacology

General Pharmacology
1. Introduction and Routes of Drug Administration

● Definition of Pharmacology: Study of drugs and their interactions with living

systems.
● Classification of Drug Administration:
○ Oral: Easy and convenient, slower absorption.
○ Intravenous (IV): Direct into bloodstream, immediate effect.
○ Intramuscular (IM): Faster than oral but slower than IV.
○ Subcutaneous (SC): Slow, steady release.
○ Topical: Local effect on skin or mucosa.
○ Inhalation: Rapid absorption through the lungs.
○ Rectal: Useful for patients who can't take oral drugs.
○ Sublingual: Under the tongue for quick absorption.

2. Pharmacokinetics: Absorption

● Definition: Process of drug transfer from the site of administration to systemic

circulation.
● Factors Affecting Absorption:
○ Drug solubility, pH, and ionization.
○ Blood flow to the absorption site.
○ Surface area of the absorption site.
○ First-pass metabolism (liver degradation before systemic circulation).

3. Pharmacokinetics: Distribution

● Definition: Dispersion of a drug throughout body fluids and tissues.

● Factors Influencing Distribution:
○ Blood flow to tissues.
○ Plasma protein binding (e.g., albumin).
○ Lipid solubility and tissue permeability.
○ Barriers like the blood-brain barrier.

4. Pharmacokinetics: Metabolism

● Definition: Chemical alteration of a drug to enhance excretion.

● Phases:
○ Phase I (Functionalization): Oxidation, reduction, hydrolysis (via cytochrome
P450 enzymes).
○ Phase II (Conjugation): Glucuronidation, sulfation, methylation.
● First-Pass Effect: Significant metabolism in the liver reduces drug bioavailability.

5. Pharmacokinetics: Excretion

● Primary Routes:
○ Kidneys: Urine (major route for water-soluble drugs).
○ Liver: Bile and feces (lipid-soluble drugs).
● Secondary Routes: Sweat, saliva, breast milk, and exhalation.

6. Kinetics of Elimination

● Zero-Order Kinetics: Fixed amount of drug eliminated per unit time (e.g., alcohol).
 ● First-Order Kinetics: Percentage of drug eliminated per unit time (most drugs follow
this).

7. Pharmacodynamics: Introduction and Enzyme Inhibitors

● Pharmacodynamics: Study of drug effects and mechanisms.

● Enzyme Inhibitors:
○ Competitive: Compete with substrate for active site.
○ Non-Competitive: Bind to an allosteric site, altering enzyme function.

8. Pharmacodynamics: Receptors

● Definition: Macromolecules drugs bind to exert effects.

● Types:
○ Ion channels (e.g., GABA).
○ G-protein-coupled receptors (e.g., adrenergic receptors).
○ Enzyme-linked receptors (e.g., insulin receptor).
○ Intracellular receptors (e.g., steroid hormones).

9. Dose Response Curve [DRC]

● Purpose: Graphical representation of drug dose vs. effect.

● Parameters:
○ Potency: Minimum dose needed for effect.
○ Efficacy: Maximum effect a drug can produce.
○ Therapeutic Index: Ratio of toxic dose to effective dose (safety margin).

10. Clinical Trials and Pharmacovigilance

● Clinical Trials:
○ Phases: Preclinical (animal studies), Phase 1 (safety), Phase 2 (efficacy),
Phase 3 (comparison), Phase 4 (post-marketing).
● Pharmacovigilance: Monitoring drug safety post-market for adverse effects.

11. Factors Affecting Drug Action

● Physiological: Age, weight, gender, genetic factors.

● Pathological: Liver/kidney diseases affecting metabolism and excretion.
● Drug Interactions: Synergistic or antagonistic effects.
● Lifestyle: Diet, smoking, and alcohol consumption.

12. Combined Effects of Drugs

● Additive Effect: Combined effect equals sum of individual effects.

● Synergistic Effect: Combined effect is greater than the sum.
● Antagonistic Effect: One drug reduces the effect of another.

13. General Pharmacology Practicals

● Common Practicals:
○ Determining drug solubility and pH.
○ Testing effects of enzyme inhibitors.
○ Plotting dose-response curves.
○ Drug interaction studies using animal models.
Autonomic Nervous System
Autonomic Nervous System
14. Basics and Cholinergic Drugs

● Basics:
○ Divisions:
■ Sympathetic: "Fight or flight," uses norepinephrine.
■ Parasympathetic: "Rest and digest," uses acetylcholine.
○ Neurotransmitters: Acetylcholine (ACh) for cholinergic and norepinephrine
(NE) for adrenergic systems.
● Cholinergic Drugs:
○ Definition: Drugs that mimic or enhance ACh action.
○ Types:
■ Direct-acting (e.g., pilocarpine for glaucoma).
■ Indirect-acting: Inhibit acetylcholinesterase (e.g., neostigmine for
myasthenia gravis).

15. Anticholinergic Drugs

● Definition: Block ACh effects on muscarinic or nicotinic receptors.

● Uses:
○ Treat bradycardia (e.g., atropine).
○ Reduce secretions during surgery.
○ Relieve motion sickness (e.g., scopolamine).
● Side Effects: Dry mouth, blurred vision, constipation, urinary retention.

16. Adrenergic Drugs

● Definition: Mimic or enhance the effects of adrenaline and norepinephrine.

● Types:
○ Alpha-Agonists: Vasoconstriction (e.g., phenylephrine for nasal
decongestion).
○ Beta-Agonists: Bronchodilation (e.g., salbutamol for asthma).
● Clinical Applications:
○ Hypotension, anaphylaxis, cardiac arrest, asthma.

17. Anti-Adrenergic Drugs

● Definition: Block effects of norepinephrine and epinephrine.

● Types:
○ Alpha-Blockers: Treat hypertension and benign prostatic hyperplasia (e.g.,
prazosin).
○ Beta-Blockers: Decrease heart rate and blood pressure (e.g., propranolol for
hypertension and angina).
● Side Effects: Fatigue, dizziness, bronchospasm (beta-blockers).

18. Glaucoma

● Definition: Eye condition with increased intraocular pressure damaging the optic
nerve.
● Drugs Used:
○ Cholinergic Drugs: Increase aqueous humor outflow (e.g., pilocarpine).
○ Beta-Blockers: Decrease aqueous humor production (e.g., timolol).
○ Prostaglandin Analogues: Increase outflow (e.g., latanoprost).
 ○ Carbonic Anhydrase Inhibitors: Decrease humor production (e.g.,
acetazolamide).

19. ANS Practicals

● Typical Practicals:
○ Observing effects of cholinergic and anticholinergic drugs on smooth
muscles.
○ Studying adrenergic and anti-adrenergic effects on isolated tissues.
○ Demonstrating drug action on animal models for glaucoma or blood pressure
regulation.
Autacoids
Autacoids
20. Histamine and Serotonin

● Histamine:
○ Location: Found in mast cells, basophils, and gastric mucosa.
○ Functions:
■ H1 Receptors: Mediate allergic reactions (e.g., itching,
bronchoconstriction).
■ H2 Receptors: Stimulate gastric acid secretion.
○ Drugs:
■ H1 Antagonists: For allergies (e.g., loratadine, cetirizine).
■ H2 Antagonists: For peptic ulcers (e.g., ranitidine, famotidine).
● Serotonin (5-HT):
○ Location: CNS, platelets, and GI tract.
○ Functions:
■ Regulates mood, appetite, and sleep.
■ Vasoconstriction and platelet aggregation.
○ Drugs:
■ Agonists: Sumatriptan for migraine.
■ Antagonists: Ondansetron for nausea/vomiting.

21. Migraine

● Definition: Neurological condition characterized by recurrent headaches.

● Pathophysiology:
○ Trigeminal nerve activation and release of vasoactive peptides.
○ Serotonin involvement in pain modulation.
● Treatment:
○ Abortive Therapy:
■ Triptans (e.g., sumatriptan).
■ NSAIDs (e.g., ibuprofen).
○ Prophylactic Therapy:
■ Beta-blockers (e.g., propranolol).
■ Anticonvulsants (e.g., topiramate).

22. PGs and NSAIDs

● Prostaglandins (PGs):
○ Derived from arachidonic acid via COX enzymes.
○ Functions:
■ PGE2: Vasodilation, fever, and pain.
■ PGF2α: Uterine contraction.
■ PGI2: Inhibits platelet aggregation.
● Non-Steroidal Anti-Inflammatory Drugs (NSAIDs):
○ Mechanism: Inhibit COX enzymes, reducing PG synthesis.
○ Examples:
■ Non-selective: Aspirin, ibuprofen.
■ COX-2 selective: Celecoxib.
○ Uses: Pain, fever, inflammation.
○ Side Effects: Gastric ulcers, kidney damage.

23. Gout and Rheumatoid Arthritis

● Gout:
○ Definition: Uric acid crystal deposition in joints causing inflammation.
○ Drugs:
■ Acute: NSAIDs (e.g., indomethacin), colchicine.
■ Chronic: Allopurinol (inhibits uric acid synthesis), febuxostat.
● Rheumatoid Arthritis (RA):
○ Definition: Autoimmune disorder causing chronic joint inflammation.
○ Drugs:
■ DMARDs: Methotrexate, hydroxychloroquine.
■ Biologics: TNF inhibitors (e.g., infliximab).
■ NSAIDs and corticosteroids for symptom relief.
Kidney
Kidney
29. Diuretics

● Definition: Drugs that increase urine production to remove excess water and salts.
● Classification:
1. Loop Diuretics:
■ Act on the Loop of Henle (thick ascending limb).
■ Example: Furosemide.
■ Uses: Pulmonary edema, heart failure.
■ Side Effects: Hypokalemia, dehydration.
2. Thiazide Diuretics:
■ Act on the distal convoluted tubule.
■ Example: Hydrochlorothiazide.
■ Uses: Hypertension, mild edema.
■ Side Effects: Hypokalemia, hyperglycemia.
3. Potassium-Sparing Diuretics:
■ Act on the collecting duct.
■ Example: Spironolactone (aldosterone antagonist).
■ Uses: Prevent hypokalemia, heart failure.
■ Side Effects: Hyperkalemia, gynecomastia.
4. Carbonic Anhydrase Inhibitors:
■ Act on the proximal tubule.
■ Example: Acetazolamide.
■ Uses: Glaucoma, altitude sickness.
■ Side Effects: Metabolic acidosis.
5. Osmotic Diuretics:
■ Increase osmotic pressure in the nephron.
■ Example: Mannitol.
■ Uses: Cerebral edema, acute renal failure.
■ Side Effects: Dehydration, electrolyte imbalance.
Endocrine System
Endocrine System
30. Pituitary Hypothalamic System

● Hypothalamic-Pituitary Axis:
○ Hypothalamus secretes releasing or inhibiting hormones regulating pituitary
hormones.
○ Anterior Pituitary:
■ Hormones: GH, ACTH, TSH, FSH, LH, prolactin.
■ Disorders:
■ Hypersecretion: Acromegaly (GH).
■ Hyposecretion: Dwarfism (GH).
○ Posterior Pituitary:
■ Hormones: ADH, oxytocin.
■ Disorders:
■ Diabetes insipidus (ADH deficiency).

31. Thyroid

● Hormones:
○ T3 (triiodothyronine), T4 (thyroxine), and calcitonin.
○ Functions: Regulate metabolism, growth, and calcium homeostasis.
● Disorders:
○ Hypothyroidism: Myxedema, Hashimoto's thyroiditis (treated with
levothyroxine).
○ Hyperthyroidism: Graves' disease (treated with antithyroid drugs like
methimazole).

32. Endocrine Pancreas

● Hormones:
○ Insulin (β-cells): Lowers blood glucose.
○ Glucagon (α-cells): Raises blood glucose.
● Disorders:
○ Diabetes Mellitus:
■ Type 1: Insulin deficiency (treated with insulin therapy).
■ Type 2: Insulin resistance (treated with metformin, sulfonylureas).
○ Hypoglycemia: Low blood glucose levels (treated with glucose).

33. Adrenal

● Cortex Hormones:
○ Glucocorticoids (cortisol): Stress response, glucose metabolism.
○ Mineralocorticoids (aldosterone): Sodium and water balance.
○ Androgens: Secondary sex characteristics.
● Medulla Hormones:
○ Epinephrine, norepinephrine: Fight or flight response.
● Disorders:
○ Addison's disease: Cortisol deficiency.
○ Cushing's syndrome: Excess cortisol.

34. Osteoporosis

● Definition: Decrease in bone density leading to fractures.

 ● Causes: Aging, menopause (low estrogen), long-term steroid use.
● Treatment:
○ Bisphosphonates (e.g., alendronate).
○ Calcium and vitamin D supplementation.
○ Hormone Replacement Therapy (HRT).

35. Sex Hormones

● Male:
○ Testosterone: Produced by testes; regulates male reproductive system and
secondary sexual characteristics.
○ Disorders: Hypogonadism (treated with testosterone replacement).
● Female:
○ Estrogen and progesterone: Regulate menstrual cycle, pregnancy, and
secondary sexual characteristics.
○ Disorders: Estrogen deficiency in menopause (treated with HRT).

36. Oral Contraceptives

● Types:
○ Combined (estrogen + progesterone): Inhibit ovulation.
○ Progesterone-only: Thicken cervical mucus and alter endometrium.
● Benefits:
○ Prevent pregnancy.
○ Regulate menstrual cycle, reduce menstrual pain.
● Side Effects:
○ Nausea, weight gain, blood clots (rare).
● Examples:
○ Combined: Ethinyl estradiol + levonorgestrel.
○ Progesterone-only: Mini-pill (norethindrone).
Central Nervous System
Central Nervous System
37. Sedatives and Hypnotics

● Sedatives: Drugs that calm the CNS and reduce anxiety without causing sleep.
○ Examples: Benzodiazepines (e.g., diazepam), barbiturates (e.g.,
phenobarbital).
○ Uses: Anxiety, muscle relaxation.
○ Side Effects: Drowsiness, dependence, tolerance.
● Hypnotics: Drugs that induce sleep.
○ Examples: Z-drugs (e.g., zolpidem), benzodiazepines (e.g., lorazepam).
○ Uses: Insomnia.
○ Side Effects: Daytime drowsiness, tolerance, dependency.

38. Neurodegenerative Diseases

● Alzheimer's Disease:
○ Pathophysiology: Progressive loss of memory and cognitive function due to
beta-amyloid plaques and tau tangles.
○ Drugs:
■ Acetylcholinesterase inhibitors (e.g., donepezil).
■ NMDA receptor antagonists (e.g., memantine).
● Parkinson's Disease:
○ Pathophysiology: Degeneration of dopaminergic neurons in the substantia
nigra.
○ Drugs:
■ Levodopa + carbidopa.
■ Dopamine agonists (e.g., pramipexole).
● Multiple Sclerosis:
○ Pathophysiology: Demyelination of CNS neurons.
○ Drugs:
■ Immunomodulators (e.g., interferon beta).
■ Steroids (e.g., methylprednisolone) for acute flare-ups.

39. Epilepsy

● Definition: A neurological disorder characterized by recurrent seizures.

● Types of Seizures:
○ Generalized: Involve both hemispheres (e.g., tonic-clonic).
○ Focal: Affect one part of the brain (e.g., partial seizures).
● Drugs:
○ First-Line: Phenytoin, valproic acid, carbamazepine.
○ For absence seizures: Ethosuximide.
○ Side Effects: Sedation, ataxia, cognitive impairment.

40. Anti-Psychotic Drugs

● First-Generation (Typical):
○ Mechanism: Dopamine receptor antagonists.
○ Examples: Haloperidol, chlorpromazine.
○ Uses: Schizophrenia, acute psychosis.
○ Side Effects: Extrapyramidal symptoms (EPS), tardive dyskinesia.
● Second-Generation (Atypical):
○ Mechanism: Dopamine and serotonin receptor antagonists.
 ○ Examples: Olanzapine, risperidone.
○ Uses: Schizophrenia, bipolar disorder.
○ Side Effects: Weight gain, metabolic syndrome.

41. Mania and Depression

● Mania:
○ Definition: State of elevated or irritable mood, hyperactivity, impulsive
behavior.
○ Drugs:
■ Mood Stabilizers: Lithium, valproate.
■ Antipsychotics: Olanzapine, risperidone.
● Depression:
○ Definition: Persistent sadness, loss of interest.
○ Drugs:
■ SSRIs: Fluoxetine, sertraline.
■ SNRIs: Venlafaxine, duloxetine.
■ Tricyclic Antidepressants (TCAs): Amitriptyline (used less due to
side effects).
○ Side Effects: Sexual dysfunction (SSRIs), sedation (TCAs).

42. Drugs of Abuse

● Opioids:
○ Examples: Heroin, morphine, oxycodone.
○ Effects: Euphoria, pain relief, respiratory depression.
○ Treatment for Overdose: Naloxone (opioid antagonist).
● Cannabis:
○ Effects: Euphoria, altered perception, dry mouth.
○ Side Effects: Memory impairment, anxiety, dependence.
● Cocaine:
○ Effects: Euphoria, increased energy, alertness.
○ Side Effects: Arrhythmias, seizures, paranoia.
● Benzodiazepines:
○ Examples: Diazepam, alprazolam.
○ Effects: Relaxation, sedation.
○ Side Effects: Dependence, overdose risk.
Anaesthesia
Anaesthesia
43. Local Anesthetics and Skeletal Muscle Relaxants

● Local Anesthetics:
○ Mechanism: Block sodium channels, preventing the initiation and conduction
of nerve impulses.
○ Types:
■ Esters: Procaine, benzocaine.
■ Amides: Lidocaine, bupivacaine.
○ Uses: Minor surgeries, dental procedures, and pain relief.
○ Side Effects: Allergic reactions (esters), CNS toxicity (e.g., seizures),
cardiovascular effects (e.g., arrhythmias).
● Skeletal Muscle Relaxants:
○ Mechanism: Reduce muscle tone by acting on the CNS or neuromuscular
junction.
○ Types:
■ Centrally Acting: Baclofen, tizanidine.
■ Peripherally Acting: Dantrolene (used for malignant hyperthermia).
○ Uses: Muscle spasms, spasticity in conditions like multiple sclerosis.
○ Side Effects: Drowsiness, weakness, respiratory depression (in high doses).

44. General Anaesthetics

● Mechanism: Induce reversible unconsciousness, muscle relaxation, and loss of

sensation.
○ Inhalational Agents:
■ Examples: Isoflurane, sevoflurane, nitrous oxide.
■ Mechanism: Potentiate GABAergic activity and inhibit excitatory
neurotransmission.
■ Side Effects: Hypotension, respiratory depression, nausea.
○ Intravenous Agents:
■ Examples: Propofol, thiopental, etomidate.
■ Mechanism: Potentiate GABA receptors (propofol), barbiturate action
(thiopental).
■ Side Effects: Respiratory depression, hypotension, pain at injection
site.
○ Adjuncts to Anesthesia:
■ Opioids: Fentanyl, morphine (for analgesia).
■ Muscle Relaxants: Rocuronium, vecuronium (to relax muscles for
surgery).
○ Side Effects: Postoperative nausea and vomiting (PONV), cardiovascular
instability, respiratory depression, emergence delirium.
Hematology
Hematology
45. Drugs Affecting Blood Flow

● Anticoagulants: Prevent the formation of blood clots.

○ Examples:
■ Heparin: Inhibits thrombin and factor Xa.
■ Warfarin: Inhibits vitamin K-dependent clotting factors.
■ Direct Oral Anticoagulants (DOACs): Dabigatran (direct thrombin
inhibitor), rivaroxaban (factor Xa inhibitor).
○ Uses: Prevention and treatment of venous thromboembolism, atrial
fibrillation, and myocardial infarction.
○ Side Effects: Bleeding, heparin-induced thrombocytopenia (HIT), warfarin
toxicity (requires monitoring).
● Antiplatelet Drugs: Inhibit platelet aggregation.
○ Examples:
■ Aspirin: Inhibits cyclooxygenase-1 (COX-1) and thromboxane A2
production.
■ Clopidogrel: P2Y12 receptor antagonist.
■ Ticagrelor: Reversible P2Y12 receptor antagonist.
○ Uses: Prevention of stroke, myocardial infarction, and in coronary artery
disease.
○ Side Effects: Bleeding, gastrointestinal irritation (aspirin), thrombotic
thrombocytopenic purpura (clopidogrel).
● Fibrinolytics (Thrombolytics): Promote clot breakdown.
○ Examples: Alteplase, reteplase.
○ Uses: Acute myocardial infarction, ischemic stroke, pulmonary embolism.
○ Side Effects: Bleeding, reperfusion injury.
● Vasodilators: Relax blood vessel walls to increase blood flow.
○ Examples: Nitroglycerin, hydralazine.
○ Uses: Angina, hypertension, heart failure.
○ Side Effects: Hypotension, dizziness, tachycardia.

46. Drugs Affecting Blood Cells

● Drugs Affecting Red Blood Cells (RBCs):

○ Erythropoiesis-Stimulating Agents (ESAs):
■ Examples: Epoetin alfa, darbepoetin.
■ Uses: Anemia (chronic kidney disease, chemotherapy-induced
anemia).
■ Side Effects: Hypertension, thrombosis, headache.
○ Iron Supplements:
■ Examples: Ferrous sulfate, iron dextran.
■ Uses: Iron-deficiency anemia.
■ Side Effects: Constipation, gastrointestinal discomfort, dark stools.
○ Vitamin B12 and Folate Supplements:
■ Uses: Pernicious anemia, megaloblastic anemia.
■ Side Effects: Rare, but high doses of B12 can cause acne or
rosacea.
● Drugs Affecting White Blood Cells (WBCs):
○ Granulocyte Colony-Stimulating Factor (G-CSF):
■ Examples: Filgrastim, pegfilgrastim.
■ Uses: Neutropenia (e.g., chemotherapy-induced).
■ Side Effects: Bone pain, fever, splenic rupture (rare).
 ○ Immunosuppressive Drugs:
■ Examples: Methotrexate, azathioprine, cyclophosphamide.
■ Uses: Autoimmune diseases, organ transplants.
■ Side Effects: Infections, bone marrow suppression.
● Drugs Affecting Platelets:
○ Thrombopoietin Receptor Agonists:
■ Examples: Romiplostim, eltrombopag.
■ Uses: Idiopathic thrombocytopenic purpura (ITP).
■ Side Effects: Thrombosis, liver toxicity.
Respiratory System
Respiratory System
47. Drugs for Cough and Bronchial Asthma

● Drugs for Cough:

○ Antitussives: Suppress the cough reflex.
■ Examples:
■ Codeine: A narcotic that reduces cough reflex by acting on the
CNS.
■ Dextromethorphan: Non-narcotic, works similarly to codeine.
■ Benzonatate: Local anesthetic action to reduce cough reflex.
■ Uses: Dry cough, nocturnal cough.
■ Side Effects: Sedation, constipation (codeine), dizziness.
○ Expectorants: Increase the clearance of mucus by reducing its viscosity.
■ Examples:
■ Guaifenesin: Common over-the-counter expectorant.
■ Uses: Productive cough, congestion.
■ Side Effects: Nausea, gastrointestinal upset.
○ Mucolytics: Break down the structure of mucus to make it easier to clear.
■ Examples:
■ Acetylcysteine: Reduces the viscosity of mucus, also used in
acetaminophen overdose.
■ Uses: Chronic obstructive pulmonary disease (COPD), cystic fibrosis.
■ Side Effects: Nausea, vomiting, bad odor.
● Drugs for Bronchial Asthma:
○ Bronchodilators: Relax bronchial smooth muscles to relieve bronchospasm.
■ Short-Acting Beta-Agonists (SABAs):
■ Examples: Albuterol, salbutamol.
■ Uses: Acute asthma attacks, quick relief.
■ Side Effects: Tachycardia, tremors.
■ Long-Acting Beta-Agonists (LABAs):
■ Examples: Salmeterol, formoterol.
■ Uses: Long-term asthma control (used in combination with
steroids).
■ Side Effects: Tachycardia, tremors, not used for acute relief.
■ Anticholinergics:
■ Examples: Ipratropium bromide, tiotropium.
■ Uses: Asthma and COPD maintenance.
■ Side Effects: Dry mouth, urinary retention.
○ Anti-inflammatory Drugs:
■ Inhaled Corticosteroids (ICS):
■ Examples: Fluticasone, budesonide.
■ Uses: Long-term asthma control, reduce inflammation.
■ Side Effects: Oral thrush, hoarseness.
■ Leukotriene Receptor Antagonists (LTRAs):
■ Examples: Montelukast, zafirlukast.
■ Uses: Asthma control, especially in children.
■ Side Effects: Headache, mood changes.
■ Mast Cell Stabilizers:
■ Examples: Cromolyn sodium.
■ Uses: Prevent asthma attacks, especially in exercise-induced
asthma.
■ Side Effects: Cough, irritation.
○ Combination Drugs:
■ Examples:
■ Fluticasone/Salmeterol (Advair): ICS + LABA.
■ Budesonide/Formoterol (Symbicort): ICS + LABA.
■ Uses: Asthma maintenance.
■ Side Effects: Similar to individual components (e.g., thrush,
tachycardia).
Gastrointestinal System
Gastrointestinal System
48. Gastrointestinal Tract

● Drugs for Acid-Related Disorders:

○ Antacids: Neutralize stomach acid.
■ Examples:
■ Magnesium hydroxide: Relieves acid indigestion.
■ Aluminum hydroxide: Used in combination with magnesium
to reduce constipation.
■ Calcium carbonate: Provides quick relief, can cause rebound
acid secretion.
■ Uses: Heartburn, acid reflux.
■ Side Effects: Constipation (aluminum), diarrhea (magnesium),
hypercalcemia (calcium carbonate).
○ Histamine-2 (H2) Receptor Antagonists: Reduce gastric acid secretion by
blocking H2 receptors.
■ Examples:
■ Ranitidine, Famotidine, Cimetidine.
■ Uses: Peptic ulcer disease, GERD (gastroesophageal reflux disease),
stress ulcers.
■ Side Effects: Headache, dizziness, confusion (especially in elderly),
drug interactions (cimetidine).
○ Proton Pump Inhibitors (PPIs): Block the proton pump, reducing gastric
acid secretion.
■ Examples:
■ Omeprazole, Pantoprazole, Esomeprazole.
■ Uses: GERD, peptic ulcers, Zollinger-Ellison syndrome.
■ Side Effects: Increased risk of infections (e.g., C. difficile), bone
fractures (long-term use), vitamin B12 deficiency.
○ Antimuscarinics (Anticholinergics): Reduce gastric acid secretion and
motility.
■ Examples:
■ Atropine, Hyoscine (Scopolamine).
■ Uses: Peptic ulcer, motion sickness.
■ Side Effects: Dry mouth, blurred vision, urinary retention.
● Drugs for Laxation:
○ Bulk-Forming Laxatives: Increase stool volume by absorbing water.
■ Examples:
■ Psyllium, Methylcellulose.
■ Uses: Constipation.
■ Side Effects: Bloating, gas, abdominal cramps.
○ Stimulant Laxatives: Stimulate peristalsis to increase bowel movements.
■ Examples:
■ Bisacodyl, Senna.
■ Uses: Acute constipation.
■ Side Effects: Abdominal cramping, diarrhea, dependence (chronic
use).
○ Osmotic Laxatives: Draw water into the colon to soften stool.
■ Examples:
■ Lactulose, Polyethylene glycol (PEG).
■ Uses: Chronic constipation, hepatic encephalopathy (lactulose).
■ Side Effects: Gas, bloating, dehydration.
 ○ Stool Softeners: Facilitate the mixing of water into stool to prevent
constipation.
■ Examples:
■ Docusate sodium.
■ Uses: Prevent constipation, especially after surgery.
■ Side Effects: Mild abdominal cramping.
● Anti-Diarrheal Drugs:
○ Opioids and Opioid Derivatives: Slow gastrointestinal motility.
■ Examples:
■ Loperamide, Diphenoxylate.
■ Uses: Acute diarrhea, traveler’s diarrhea.
■ Side Effects: Constipation, abdominal discomfort.
○ Bismuth Subsalicylate: Has anti-inflammatory, antimicrobial, and
antisecretory effects.
■ Examples: Pepto-Bismol.
■ Uses: Diarrhea, nausea, and upset stomach.
■ Side Effects: Black stools, constipation.
● Antiemetics: Prevent or treat nausea and vomiting.
○ Examples:
■ Ondansetron (5-HT3 antagonist), Promethazine (antihistamine),
Metoclopramide (dopamine antagonist).
■ Uses: Postoperative nausea, chemotherapy-induced nausea.
■ Side Effects: Drowsiness (promethazine), QT prolongation
(ondansetron), extrapyramidal symptoms (metoclopramide).
● Drugs for Inflammatory Bowel Disease (IBD):
○ Corticosteroids: Reduce inflammation.
■ Examples:
■ Prednisone, Budesonide.
■ Uses: Acute flare-ups of IBD (Crohn’s disease, ulcerative colitis).
■ Side Effects: Weight gain, hypertension, osteoporosis (long-term
use).
○ Immunosuppressive Agents: Suppress immune response to reduce
inflammation.
■ Examples:
■ Azathioprine, Methotrexate.
■ Uses: Maintenance therapy in IBD.
■ Side Effects: Bone marrow suppression, infections.
○ Biologic Agents: Target specific immune pathways.
■ Examples:
■ Infliximab, Adalimumab (TNF inhibitors).
■ Uses: Moderate to severe IBD.
■ Side Effects: Infections, malignancy.
Antimicrobial Agents
Antimicrobial Agents
49. General Points About Antimicrobials

● Definition: Drugs used to treat infections caused by microorganisms (bacteria, fungi,

viruses, and parasites).
● Types:
○ Antibacterial (for bacteria).
○ Antiviral (for viruses).
○ Antifungal (for fungi).
○ Antiparasitic (for parasites).
● Mechanisms of Action: Inhibit microbial growth or kill the microorganisms through
different mechanisms.
● Spectrum of Activity:
○ Broad-spectrum antibiotics: Effective against a wide range of
microorganisms.
○ Narrow-spectrum antibiotics: Effective against specific types of
microorganisms.
● Resistance: The ability of microbes to resist the effects of drugs due to mutation,
overuse, or misuse.

50. Cell Wall Synthesis Inhibitors

● Mechanism of Action: Inhibit the synthesis of the bacterial cell wall, leading to cell
lysis.
● Examples:
○ Penicillins (e.g., Amoxicillin, Penicillin G): Block transpeptidase enzymes
involved in cross-linking peptidoglycan.
○ Cephalosporins (e.g., Ceftriaxone, Cefazolin): Similar mechanism to
penicillins, used for a broader range of infections.
○ Carbapenems (e.g., Imipenem, Meropenem): Broad-spectrum antibiotics for
resistant infections.
○ Glycopeptides (e.g., Vancomycin): Inhibit peptidoglycan synthesis by
binding to D-alanine, interfering with cell wall formation.
● Uses: Bacterial infections, especially those caused by Gram-positive bacteria.
● Side Effects: Allergic reactions, gastrointestinal disturbances.

51. Other Mechanisms of Antimicrobials

● Protein Synthesis Inhibitors:

○ Macrolides (e.g., Erythromycin, Azithromycin): Bind to the 50S ribosomal
subunit, inhibiting protein synthesis.
○ Aminoglycosides (e.g., Gentamicin, Amikacin): Bind to the 30S ribosomal
subunit, causing misreading of mRNA.
○ Tetracyclines (e.g., Doxycycline): Bind to the 30S ribosomal subunit,
blocking tRNA attachment.
○ Chloramphenicol: Inhibits peptidyl transferase on the 50S subunit.
● Nucleic Acid Synthesis Inhibitors:
○ Fluoroquinolones (e.g., Ciprofloxacin, Levofloxacin): Inhibit bacterial DNA
gyrase and topoisomerase IV, preventing DNA replication.
○ Rifampin: Inhibits bacterial RNA polymerase, preventing transcription.
● Metabolism Inhibitors:
○ Sulfonamides (e.g., Sulfamethoxazole): Inhibit folic acid synthesis, blocking
bacterial growth.
 ○ Trimethoprim: Inhibits bacterial dihydrofolate reductase, blocking folate
synthesis.
● Cell Membrane Disruptors:
○ Polymyxins (e.g., Polymyxin B): Disrupt bacterial cell membrane, leading to
leakage of cellular contents.

52. Tuberculosis and Leprosy

● Tuberculosis (TB):
○ First-line drugs:
■ Isoniazid: Inhibits mycolic acid synthesis in the bacterial cell wall.
■ Rifampin: Inhibits RNA synthesis.
■ Pyrazinamide: Mechanism unclear, but disrupts mycobacterial cell
membrane.
■ Ethambutol: Inhibits arabinosyl transferase, disrupting the cell wall.
○ Second-line drugs: Used in drug-resistant TB, including Streptomycin,
Ciprofloxacin.
○ Treatment Regimen: Combination therapy for 6-9 months to prevent
resistance.
● Leprosy:
○ First-line drugs:
■ Dapsone: Inhibits folate synthesis.
■ Rifampin: Inhibits RNA synthesis.
■ Clofazimine: Binds to DNA, inhibiting replication.
○ Treatment: Long-term multidrug therapy (MDT) to prevent resistance.

53. Antiviral Drugs

● Mechanisms of Action:
○ Inhibit Viral Entry: Prevent the virus from entering the host cell.
■ Examples: Amantadine, Oseltamivir (Neuraminidase inhibitors for
influenza).
○ Inhibit Viral Replication: Block viral DNA/RNA synthesis.
■ Examples: Acyclovir (for herpesviruses), Lamivudine (for HIV and
hepatitis B).
○ Inhibit Viral Assembly/Release: Prevent the assembly or release of new
virions.
■ Examples: Protease inhibitors (e.g., Ritonavir for HIV), Zidovudine
(NRTI for HIV).
● Uses: HIV/AIDS, herpes, influenza, hepatitis B and C.
● Side Effects: GI disturbances, hepatotoxicity, hematologic toxicity.

54. Antifungal Drugs

● Mechanisms of Action:
○ Inhibit Ergosterol Synthesis: Disrupt the fungal cell membrane.
■ Examples: Azoles (e.g., Fluconazole, Itraconazole), Terbinafine.
○ Disrupt Cell Wall: Inhibit glucan synthesis in the fungal cell wall.
■ Examples: Echinocandins (e.g., Caspofungin).
○ Bind to Fungal DNA: Inhibit DNA synthesis.
■ Example: Flucytosine.
● Uses: Fungal infections such as candidiasis, aspergillosis, dermatophytosis.
● Side Effects: Hepatotoxicity, rash, GI disturbances.

55. Anti-Parasitic Drugs

● Anti-Malaria:
○ Chloroquine: Inhibits heme polymerization within the parasite.
○ Artemisinin: Binds to parasite molecules and generates free radicals.
○ Mefloquine: Inhibits parasite growth by affecting heme detoxification.
● Anti-Helminths:
○ Albendazole: Inhibits tubulin polymerization in worms, leading to paralysis
and death.
○ Mebendazole: Similar mechanism to albendazole, used for intestinal
helminths.
○ Praziquantel: Disrupts the integrity of the parasite’s cell membrane.
● Anti-Protozoa:
○ Metronidazole: Inhibits DNA synthesis in protozoa and anaerobic bacteria.
○ Pentamidine: Used for protozoal infections like leishmaniasis and sleeping
sickness.
● Uses: Malaria, helminthic infections, amoebiasis, giardiasis, leishmaniasis.
● Side Effects: Gastrointestinal disturbances, headache, hepatotoxicity.
Anti-Cancer Drugs &
Immunosuppressants
Anti-Cancer Drugs & Immunosuppressants
56. Cytotoxic Anticancer Drugs

● Mechanism of Action: These drugs inhibit the growth and division of cancer cells by
damaging their DNA, interfering with cell division, or causing cell death.
● Classes:
○ Alkylating Agents:
■ Examples: Cyclophosphamide, Ifosfamide.
■ Mechanism: Add alkyl groups to DNA, causing cross-linking and
preventing DNA replication.
■ Uses: Lymphoma, leukemia, solid tumors.
■ Side Effects: Myelosuppression, nausea, vomiting, bladder toxicity
(with cyclophosphamide).
○ Antimetabolites:
■ Examples: Methotrexate, 5-Fluorouracil (5-FU).
■ Mechanism: Mimic normal metabolites, disrupting DNA/RNA
synthesis and causing cell cycle arrest.
■ Uses: Leukemias, solid tumors (colon, breast).
■ Side Effects: Bone marrow suppression, mucositis, liver toxicity
(methotrexate).
○ Mitotic Inhibitors:
■ Examples: Vincristine, Paclitaxel.
■ Mechanism: Interfere with microtubule formation or function, blocking
mitosis.
■ Uses: Lymphoma, breast cancer, ovarian cancer.
■ Side Effects: Peripheral neuropathy (vincristine), myelosuppression
(paclitaxel).
○ Topoisomerase Inhibitors:
■ Examples: Doxorubicin, Etoposide.
■ Mechanism: Inhibit topoisomerases, enzymes needed for DNA
replication and repair.
■ Uses: Leukemias, lymphomas, solid tumors.
■ Side Effects: Cardiotoxicity (doxorubicin), myelosuppression, nausea.
● General Side Effects: Myelosuppression (bone marrow suppression), nausea,
vomiting, hair loss, mucositis, organ toxicity (liver, heart).

57. Targeted Anticancer Drugs

● Mechanism of Action: These drugs target specific molecules or pathways involved

in cancer cell growth, minimizing damage to normal cells.
● Examples:
○ Tyrosine Kinase Inhibitors:
■ Examples: Imatinib (for chronic myeloid leukemia), Erlotinib (for
non-small cell lung cancer).
■ Mechanism: Inhibit the activity of specific tyrosine kinases involved in
cancer cell signaling.
■ Uses: Leukemias, solid tumors (lung, pancreatic).
■ Side Effects: Fatigue, nausea, diarrhea, rash.
○ Monoclonal Antibodies (discussed further below).
○ Proteasome Inhibitors:
■ Examples: Bortezomib.
■ Mechanism: Inhibit proteasomes, preventing degradation of proteins,
leading to accumulation of dysfunctional proteins in cancer cells.
 ■ Uses: Multiple myeloma.
■ Side Effects: Peripheral neuropathy, myelosuppression,
gastrointestinal issues.
○ Angiogenesis Inhibitors:
■ Examples: Bevacizumab.
■ Mechanism: Inhibit the formation of new blood vessels (angiogenesis)
that supply tumors.
■ Uses: Colorectal cancer, lung cancer.
■ Side Effects: Hypertension, bleeding, proteinuria.

58. Immunosuppressants

● Mechanism of Action: These drugs suppress the immune system to prevent

rejection of transplanted organs or treat autoimmune diseases.
● Classes:
○ Calcineurin Inhibitors:
■ Examples: Cyclosporine, Tacrolimus.
■ Mechanism: Inhibit calcineurin, preventing the activation of T-cells.
■ Uses: Organ transplantation, autoimmune diseases.
■ Side Effects: Nephrotoxicity, hypertension, tremors.
○ Antiproliferative Agents:
■ Examples: Azathioprine, Mycophenolate mofetil.
■ Mechanism: Inhibit purine synthesis, blocking T-cell and B-cell
proliferation.
■ Uses: Organ transplantation, autoimmune diseases (lupus,
rheumatoid arthritis).
■ Side Effects: Bone marrow suppression, infections, gastrointestinal
disturbances.
○ Corticosteroids:
■ Examples: Prednisone, Methylprednisolone.
■ Mechanism: Suppress inflammation and immune responses by
inhibiting cytokine production.
■ Uses: Organ transplantation, autoimmune diseases.
■ Side Effects: Weight gain, osteoporosis, infection risk, hyperglycemia.
○ Monoclonal Antibodies:
■ Examples: Rituximab, Basiliximab.
■ Mechanism: Target specific immune cells (e.g., B-cells, T-cells) to
suppress immune response.
■ Uses: Organ transplantation, autoimmune diseases.
■ Side Effects: Infusion reactions, infections.

59. Monoclonal Antibodies

● Mechanism of Action: These are laboratory-made antibodies designed to target

specific antigens found on cancer cells or immune cells.
● Classes:
○ Anti-Cancer Monoclonal Antibodies:
■ Examples:
■ Trastuzumab (for HER2-positive breast cancer).
■ Rituximab (for non-Hodgkin lymphoma, rheumatoid arthritis).
■ Mechanism: Bind to specific tumor antigens, inhibiting cancer cell
growth and promoting immune-mediated killing.
■ Side Effects: Infusion reactions, fever, chills, potential for tumor lysis
syndrome.
○ Immunosuppressive Monoclonal Antibodies:
 ■ Examples: Basiliximab, Daclizumab.
■ Mechanism: Block the IL-2 receptor on T-cells, preventing T-cell
activation and proliferation.
■ Uses: Organ transplantation (kidney, liver), autoimmune diseases.
■ Side Effects: Increased risk of infection, allergic reactions,
gastrointestinal disturbances.
● General Uses of Monoclonal Antibodies:
○ Cancer (targeting tumor antigens like HER2, CD20).
○ Autoimmune diseases (e.g., rheumatoid arthritis, multiple sclerosis).
○ Organ transplantation (preventing rejection).
Drug Interactions and Antidotes
60. Drug Interactions and Antidotes
Drug Interactions

● Definition: A drug interaction occurs when one drug affects the pharmacokinetics or
pharmacodynamics of another drug, potentially altering its effectiveness or causing
harmful side effects.
● Types:
1. Pharmacokinetic Interactions:
■ Involves changes in the absorption, distribution, metabolism, or
excretion of a drug due to the presence of another drug.
■ Example:
■ CYP450 Enzyme Inhibition: Drugs like Ketoconazole inhibit
CYP450 enzymes, leading to increased levels of drugs
metabolized by these enzymes (e.g., Warfarin).
■ Absorption Effects: Antacids (e.g., Aluminum hydroxide)
can reduce the absorption of drugs like Tetracycline by
altering stomach pH.
2. Pharmacodynamic Interactions:
■ Occur when two drugs have additive, synergistic, or antagonistic
effects on the same physiological system.
■ Example:
■ Additive Effect: Two central nervous system depressants like
Diazepam and Alcohol increase sedation.
■ Antagonistic Effect: Beta-blockers (e.g., Propranolol) may
oppose the effect of Beta-agonists (e.g., Salbutamol) in
asthma treatment.
3. Drug-Food Interactions:
■ Food can alter the absorption, metabolism, or elimination of drugs.
■ Example: Grapefruit juice inhibits CYP3A4, affecting the metabolism
of drugs like Statins (e.g., Atorvastatin).
4. Drug-Disease Interactions:
■ A drug may worsen an existing medical condition.
■ Example: NSAIDs (e.g., Ibuprofen) can worsen peptic ulcer disease
or kidney function in individuals with renal impairment.

Antidotes

● Definition: An antidote is a substance that can neutralize or counteract the harmful

effects of a drug or toxin.
● Types of Antidotes:
1. Specific Antidotes:
■ Naloxone: Used for opioid overdose (e.g., Heroin, Morphine).
■ Atropine: Used for poisoning by organophosphates (e.g., in
insecticides) and nerve agents (e.g., Sarin).
■ Vitamin K: Used to reverse the anticoagulant effects of Warfarin
overdose.
■ Digoxin-specific antibody: Used in case of Digoxin toxicity (for
cardiac arrhythmias).
2. Non-Specific Antidotes:
■ Activated Charcoal: Adsorbs a wide range of toxins if administered
within an hour of ingestion.
■ Sodium bicarbonate: Used in aspirin poisoning to alkalinize urine,
enhancing renal elimination of salicylates.
 3. Chelating Agents:
■ Dimercaprol, EDTA: Used to treat heavy metal poisoning (e.g., Lead,
Arsenic, Mercury).
■ Deferoxamine: Used for iron poisoning.
4. Enzyme Activation:
■ Fomepizole: Used to treat Methanol or Ethylene glycol poisoning by
inhibiting alcohol dehydrogenase, preventing the formation of toxic
metabolites.

Clinical Relevance

● Polypharmacy: The use of multiple medications, especially in elderly patients,

increases the risk of drug interactions. It's essential to monitor for interactions to
prevent adverse outcomes.
● Individualization of Therapy: Adjusting dosages or choosing alternative drugs may
be necessary in the presence of significant interactions or contraindications.
Miscellaneous Topics
61. Miscellaneous Topics
This category encompasses various topics that don't fit neatly into specific areas but are still
significant in pharmacology. Here are some important ones:

1. Pharmacogenomics

● Definition: The study of how an individual's genetic makeup affects their response to
drugs.
● Importance: Helps in tailoring drug therapy based on genetic factors, optimizing drug
efficacy, and minimizing side effects.
● Example:
○ CYP450 Enzyme Variants: Variations in the CYP2C19 gene can affect the
metabolism of Clopidogrel, influencing its effectiveness in preventing blood
clots.

2. Bioavailability

● Definition: The fraction of an administered dose of a drug that reaches the systemic
circulation in an active form.
● Factors affecting bioavailability:
○ Route of administration: Oral drugs have lower bioavailability due to first-
pass metabolism in the liver.
○ Solubility: Drugs with poor water solubility may have reduced absorption.
○ Formulation: Immediate-release versus controlled-release forms can
influence how much drug is available in the bloodstream.

3. Therapeutic Index

● Definition: The ratio between the toxic dose and the therapeutic dose of a drug.
● Importance: A higher therapeutic index indicates a safer drug with a wider margin
between effective and toxic doses.
● Example: Warfarin has a narrow therapeutic index, meaning that small changes in
dosage can lead to toxicity or lack of efficacy.

4. Toxicology

● Definition: The study of harmful effects of drugs and chemicals on living organisms.
● Common Toxic Reactions:
○ Acute Toxicity: Immediate effects after drug exposure (e.g., overdose of
opioids).
○ Chronic Toxicity: Long-term effects after repeated drug use (e.g., liver
damage with prolonged Paracetamol use).
○ Organ-Specific Toxicity: Drugs like Methotrexate can specifically affect
organs like the liver and kidneys.

5. Drug Development Process

● Stages:
1. Discovery and Preclinical Testing: Laboratory and animal studies to assess
the drug's safety and efficacy.
2. Clinical Trials: Involves 3 phases:
■ Phase 1: Small group of healthy volunteers to evaluate safety.
■ Phase 2: Involves patients to assess efficacy and side effects.
 ■
Phase 3: Large-scale trials to confirm efficacy and monitor side effects
in diverse populations.
3. Post-Market Surveillance: Ongoing monitoring for long-term effects after
approval (Pharmacovigilance).

6. Vaccines and Immunization

● Definition: Biological preparations that provide acquired immunity to a specific

infectious disease.
● Types of Vaccines:
○ Live Attenuated Vaccines: Contain weakened forms of the virus or bacteria
(e.g., MMR, BCG).
○ Inactivated Vaccines: Contain killed pathogens (e.g., Polio).
○ Subunit Vaccines: Contain fragments of the pathogen (e.g., Hepatitis B).
● Importance: Vaccines are essential for disease prevention and public health,
especially in controlling outbreaks of infectious diseases.

7. Nutraceuticals

● Definition: Food products that provide health benefits beyond basic nutrition (often
derived from plants or herbs).
● Examples:
○ Omega-3 fatty acids (from fish oil) for cardiovascular health.
○ Probiotics for gut health.
● Regulation: Often less strictly regulated than drugs, but may still interact with
medications and affect their efficacy.

8. Drug Dependence and Addiction

● Definition: A condition where the body becomes reliant on a drug to function, leading
to physical or psychological dependence.
● Drugs of Abuse:
○ Opioids (e.g., Heroin, Morphine): Lead to euphoria and pain relief but are
highly addictive.
○ Benzodiazepines (e.g., Diazepam): Used for anxiety and sleep disorders but
can lead to dependence.
○ Cocaine and Nicotine: Central nervous system stimulants with high potential
for abuse.

9. Drug Regulation and Legislation

● Regulatory Agencies:
○ FDA (Food and Drug Administration): U.S. agency responsible for the
approval of drugs and ensuring their safety and efficacy.
○ EMA (European Medicines Agency): Regulates pharmaceuticals in the
European Union.
● Controlled Substances: Drugs classified based on their potential for abuse and
addiction (e.g., Schedule I: High potential for abuse, no accepted medical use,
Schedule IV: Lower potential for abuse, e.g., Alprazolam).

10. Drug Storage and Stability

● Factors Affecting Stability:

○ Temperature: Drugs need to be stored at specific temperatures (e.g., some
need refrigeration).
 ○ Light: Drugs sensitive to light can degrade (e.g., Nitroglycerin).
○ Humidity: Some drugs are hygroscopic and must be kept dry (e.g.,
Furosemide).

11. Ethical Considerations in Pharmacology

● Informed Consent: Patients must be informed about the benefits and risks of
treatments.
● Clinical Trial Ethics: The use of placebos, balancing risks, and ensuring patient
safety during trials.
● Access to Medicine: The issue of affordability and access to essential drugs,
especially in low-income populations.
New Drugs
62. New Drugs
1. Drug Discovery and Development

● Discovery: Identifying potential new drug targets through research in molecular

biology, genomics, and disease mechanisms.
● Preclinical Studies: Initial testing in laboratories and animal models to assess
safety, efficacy, and toxicity.
● Clinical Trials: Drugs undergo rigorous testing in humans through phased trials to
confirm their safety and effectiveness.

2. Types of New Drugs

● Small Molecule Drugs:

○ Definition: Typically synthetic, these drugs interact with biological targets at
the molecular level (e.g., Statins, Tylenol).
○ Example: Imatinib (Gleevec): A targeted therapy for chronic myelogenous
leukemia (CML).
● Biologics:
○ Definition: Large, complex molecules derived from living organisms, used to
treat various diseases (e.g., cancer, autoimmune diseases).
○ Example: Monoclonal Antibodies (e.g., Adalimumab (Humira) for
rheumatoid arthritis).
● Gene Therapies:
○ Definition: Involves inserting, altering, or removing genes within an
individual’s cells to treat or prevent disease.
○ Example: Luxturna for inherited retinal dystrophy.
● Cell-based Therapies:
○ Definition: Involves the use of live cells to treat diseases or regenerate
damaged tissues.
○ Example: Stem cell therapies for repairing heart or liver damage.

3. Advancements in New Drug Development

● CRISPR-Cas9 Technology: A revolutionary gene-editing tool used to develop

treatments for genetic diseases like Sickle Cell Anemia and Cystic Fibrosis.
● Artificial Intelligence in Drug Discovery: AI is now employed to analyze large
datasets, identify drug candidates, and predict drug efficacy and side effects,
accelerating the discovery process.
● Personalized Medicine: Tailoring drug treatments based on an individual’s genetic
makeup to maximize efficacy and minimize side effects.
○ Example: Herceptin (Trastuzumab) for breast cancer, targeting HER2-
positive cancer cells.

4. Recent New Drugs Approved

● Brolucizumab (Beovu): A new biologic for the treatment of age-related macular

degeneration (AMD).
● Dupilumab (Dupixent): A monoclonal antibody approved for treating conditions like
eczema and asthma.
● Atezolizumab (Tecentriq): An immune checkpoint inhibitor used for treating various
cancers, including non-small cell lung cancer.

5. Challenges in New Drug Development

 ● High Failure Rate: Despite significant investments, most drug candidates fail in
clinical trials due to lack of efficacy or safety issues.
● Cost: The development of new drugs can cost billions of dollars, and the time
required for approval can span over a decade.
● Regulatory Hurdles: New drugs must undergo extensive evaluation by regulatory
agencies like the FDA and EMA before reaching the market.
● Resistance to Treatment: The emergence of resistance, especially in antimicrobial
drugs (e.g., antibiotics), limits the effectiveness of new drugs in certain areas.

6. Regulation of New Drugs

● Regulatory Agencies:
○ FDA (Food and Drug Administration): The U.S. agency responsible for
approving new drugs for public use.
○ EMA (European Medicines Agency): Regulates the approval and
monitoring of drugs in the EU.
● Approval Process:
○ Phase I: Safety testing in healthy volunteers.
○ Phase II: Effectiveness testing in small groups of patients.
○ Phase III: Larger trials to confirm effectiveness and monitor side effects.
○ Phase IV: Post-marketing surveillance to track long-term effects and rare
adverse reactions.

7. Biotechnology and New Drugs

● Biotechnological Innovations:
○ Gene Editing: Advances in CRISPR technology are being used to treat
genetic disorders by directly modifying DNA.
○ Biological Pathways: Targeting specific molecular pathways, like those
involved in cancer cell proliferation, can help create more effective and less
toxic drugs.

8. Examples of Recent Breakthrough Drugs

● Kymriah: A CAR T-cell therapy for treating certain types of leukemia and lymphoma.
● Zolgensma: A gene therapy for spinal muscular atrophy, a rare genetic disorder in
children.
● Keytruda: A checkpoint inhibitor used to treat various cancers by blocking the PD-1
pathway, allowing the immune system to target and destroy cancer cells.

9. Future Trends in New Drug Development

● Targeted Therapies: Drugs that specifically target molecular pathways involved in

diseases like cancer or Alzheimer’s.
● Regenerative Medicine: Developing drugs that promote tissue regeneration, such
as stem cell therapies or tissue-engineered products.
● Nanomedicine: Using nanoparticles to deliver drugs precisely to target sites within
the body, improving efficacy and reducing side effects.