Summary of Pharmacology B category Part 2

Explore the comprehensive summary of Pharmacology Part 2 b category punjab pharmacy council, covering key drug classes, mechanisms of action, therapeutic uses, and side effects. Perfect for B-Category students, this guide simplifies complex concepts like pharmacokinetics, autonomic drugs, antibiotics, analgesics, cardiovascular medications, and more. A must-have resource for quick revision and exam success!

Concept Map for Autonomic Nervous System (ANS)

1. Autonomic Nervous System (ANS)

• Coordinates body functions with the endocrine system
• Controls visceral functions (involuntary)

1. Neuron

• Basic unit of the nervous system
• Types:
  • Motor Neuron: Carries impulses from CNS to effectors
  • Sensory Neuron: Carries impulses to CNS

1. Neurotransmitters

• Facilitate signal transmission between neurons
• Types include acetylcholine (for parasympathetic) and norepinephrine (for sympathetic)

1. Efferent Neurons

• Preganglionic: Originates in CNS and synapses in ganglia
• Postganglionic: Connects from ganglia to effector organs

1. Divisions of ANS

• Sympathetic Nervous System: “Fight or Flight” responses
  • Increases heart rate, dilates pupils, dilates bronchioles
• Parasympathetic Nervous System: “Rest and Digest” responses
  • Lowers heart rate, constricts pupils, stimulates digestion
• Enteric Nervous System (ENS): Manages gastrointestinal functions independently

1. Drugs Affecting ANS

• Cholinergic Drugs: Mimic or inhibit acetylcholine
• Adrenergic Drugs: Affect adrenaline and noradrenaline receptors
  • Agonists: Stimulate receptors
  • Antagonists: Block receptors

---

Tabular Summary for Autonomic Nervous System (ANS)

Topic	Description
Autonomic Nervous System	Controls involuntary body functions, coordinated with endocrine system for regulating bodily functions.
Neuron Types	Motor Neuron (Efferent), Sensory Neuron (Afferent)
Neurotransmitters	Chemicals that transmit signals across synapses; e.g., acetylcholine (ANS) and norepinephrine (SNS)
Efferent Neurons	Divided into Preganglionic (originates in CNS) and Postganglionic (connects to organs)
Sympathetic NS	“Fight or Flight” – Increases heart rate, dilates pupils and bronchioles
Parasympathetic NS	“Rest and Digest” – Reduces heart rate, constricts pupils, promotes digestion
Enteric NS	Controls gastrointestinal functions independently, innervates GIT, pancreas, and gallbladder
Cholinergic Drugs	Drugs that act on acetylcholine pathways (agonists and antagonists)
Adrenergic Drugs	Drugs that target adrenaline receptors, classified as agonists or antagonists
Example Drugs	Cholinergic Agonists (e.g., Acetylcholine), Adrenergic Agonists (e.g., Epinephrine)
Drug Effects on Organs	Sympathetic action vs. Parasympathetic action – such as on the heart, eye, GIT, respiratory tract

Summary of Drugs used

Drug Class	Drug Name	Mechanism of Action	Therapeutic Use	Adverse Effects
Cholinergic Agonists	Acetylcholine	Directly stimulates muscarinic and nicotinic receptors	Induces miosis during eye surgery	Bradycardia, bronchoconstriction, diarrhea
	Physostigmine	Inhibits acetylcholinesterase (reversible)	Treats glaucoma, myasthenia gravis	Convulsions, bradycardia, muscle cramps
	Echothiophate	Inhibits acetylcholinesterase (irreversible)	Chronic glaucoma	Excessive salivation, muscle weakness
	Pralidoxime	Reactivates acetylcholinesterase	Antidote for organophosphate poisoning	Muscle weakness, dizziness
Cholinergic Antagonists	Atropine	Blocks muscarinic receptors	Treats bradycardia, antidote for cholinergic drugs	Dry mouth, blurred vision, urinary retention
	Mecamylamine	Ganglionic blocker at nicotinic receptors	Emergency hypertension	Hypotension, dry mouth, constipation
Neuromuscular Blockers	Tubocurarine	Competitive blocker at nicotinic receptors	Muscle relaxation in surgery	Respiratory depression, hypotension
	Succinylcholine	Depolarizes nicotinic receptors, causing initial contraction followed by paralysis	Rapid intubation	Hyperkalemia, malignant hyperthermia
Adrenergic Agonists	Epinephrine	Activates α and β adrenergic receptors	Anaphylaxis, cardiac arrest	Tachycardia, hypertension
	Amphetamine	Releases norepinephrine, inhibits MAO	ADHD, narcolepsy	Insomnia, hypertension, dependency
	Ephedrine	Mixed action on α and β receptors	Nasal congestion, hypotension	Insomnia, tachycardia
Adrenergic Antagonists	Prazosin	Blocks α1 receptors	Hypertension, BPH	Dizziness, hypotension
	Propranolol	Non-selective β blocker	Hypertension, angina, arrhythmias	Bradycardia, bronchospasm
	Reserpine	Inhibits storage of norepinephrine	Hypertension	Depression, nasal congestion

“Unit IV: Central Nervous System (CNS)

Drug Class	Drug Name	Mechanism of Action	Therapeutic Use	Adverse Effects
Neurodegenerative Disease Drugs	Levodopa	Precursor to dopamine, converted in CNS	Parkinson’s disease	Nausea, vomiting, hypotension, involuntary movements
Anxiolytics & Hypnotics	Benzodiazepines	Enhance GABA effects at GABAa receptors	Anxiety, insomnia, muscle relaxation	Drowsiness, confusion, dependence
	Phenobarbitone	Enhances GABA activity, CNS depressant	Seizures, anesthesia	Respiratory depression, sedation, overdose potential
	Buspirone	Non-benzodiazepine, works on serotonin receptors	Generalized anxiety disorder	Dizziness, headache, nervousness
CNS Stimulants	Cocaine	Blocks reuptake of norepinephrine, dopamine, serotonin	Local anesthetic in ENT surgeries	Tachycardia, hypertension, addiction
	Nicotine	Stimulates ganglia at low dose, CNS stimulation	Cognitive improvement	Increased blood pressure, heart rate, addiction
Antidepressants	Fluoxetine	Selective serotonin reuptake inhibitor (SSRI)	Depression, anxiety disorders	Insomnia, headache, sexual dysfunction
	Duloxetine	Inhibits serotonin and norepinephrine reuptake	Depression, anxiety	Dry mouth, fatigue, liver concerns
	Mirtazapine	Blocks presynaptic α2 receptors, increases serotonin/norepinephrine	Depression, especially with insomnia	Weight gain, sedation
	Amitriptyline	Blocks reuptake of serotonin and norepinephrine	Major depressive disorder, neuropathic pain	Dry mouth, urinary retention, sedation
	Phenelzine	Monoamine oxidase inhibitor, increases neurotransmitter availability	Depression	Hypertension, headache, interaction with tyramine
Neuroleptics (Antipsychotics)	Chlorpromazine	Blocks dopamine receptors	Schizophrenia, manic states	Movement disorders, constipation, dry mouth
	Haloperidol	High-potency dopamine receptor blocker	Schizophrenia	Extrapyramidal symptoms, tardive dyskinesia
	Clozapine	Blocks dopamine and serotonin receptors	Schizophrenia (especially resistant cases)	Agranulocytosis, sedation, hypersalivation
Antiepileptic Drugs	Gabapentin	GABA analog, mechanism unclear	Partial seizures, neuropathic pain	Dizziness, ataxia, fatigue
	Phenytoin	Blocks sodium channels, stabilizes neuronal activity	Seizures	Gum hypertrophy, rash, dizziness

Unit V: Cardiovascular System

Drug Class	Drug Name	Mechanism of Action	Therapeutic Use	Adverse Effects
ACE Inhibitors	Captopril	Inhibits ACE, reduces angiotensin-II, and bradykinin	Hypertension, heart failure	Dry cough, hypotension, renal insufficiency
Angiotensin Receptor Blockers (ARBs)	Losartan	Blocks AT1 receptor, reduces angiotensin-II action	Hypertension, heart failure	Dizziness, hyperkalemia, hypotension
Beta-Blockers	Propranolol	Blocks β1 and β2 receptors, reduces cardiac output	Hypertension, angina, arrhythmias	Bradycardia, fatigue, bronchospasm
Diuretics	Spironolactone	Inhibits aldosterone, increases Na+ excretion	Heart failure, hypertension	Hyperkalemia, gynecomastia
Vasodilators	Sodium Nitroprusside	Directly dilates arterioles and veins	Hypertensive emergencies	Headache, nausea, hypotension
Inotropic Agents	Digoxin	Increases intracellular calcium, improves cardiac output	Heart failure, atrial fibrillation	Nausea, vomiting, vision disturbances
Antianginal Drugs	Nitroglycerin	Releases nitric oxide, dilates coronary arteries	Angina pectoris	Headache, hypotension, tachycardia
Calcium Channel Blockers	Verapamil	Inhibits Ca2+ influx, reduces vascular resistance	Hypertension, angina, arrhythmias	Constipation, hypotension, bradycardia
Antiarrhythmic Drugs (Class I)	Quinidine	Na+ channel blocker, stabilizes cardiac rhythm	Atrial fibrillation, ventricular arrhythmias	Tinnitus, nausea, arrhythmia
Antiarrhythmic Drugs (Class III)	Amiodarone	Prolongs action potential, blocks multiple ion channels	Severe refractory arrhythmias	Tremor, lung toxicity, skin discoloration

Unit VI: Gastrointestinal Drugs

Drug Class	Drug Name	Mechanism of Action	Therapeutic Use	Adverse Effects
Antimicrobial Agents	Metronidazole	Disrupts DNA synthesis in bacteria	Peptic ulcer disease (H. pylori)	Nausea, metallic taste, dizziness
H2 Receptor Blockers	Cimetidine	Blocks H2 receptors, reducing gastric acid secretion	Peptic ulcer, GERD	Gynecomastia, confusion, dizziness
Proton Pump Inhibitors	Omeprazole	Inhibits H+/K+ ATPase in gastric parietal cells	Peptic ulcer, GERD	Headache, diarrhea, abdominal pain
Prostaglandin Analogues	Misoprostol	Increases mucus production, protects gastric mucosa	Peptic ulcer (NSAID-induced)	Diarrhea, abdominal pain
Antacids	Aluminum Hydroxide	Neutralizes stomach acid	Acid indigestion, heartburn	Constipation, phosphate depletion
Mucosal Protectants	Sucralfate	Forms protective barrier over ulcers	Peptic ulcer	Constipation, dry mouth
Antimotility Agents	Loperamide	Slows intestinal motility by acting on opioid receptors	Diarrhea	Constipation, drowsiness
Adsorbents	Aluminum Hydroxide	Adsorbs toxins, provides protective layer in gut	Diarrhea	Constipation, dehydration
Laxatives (Irritants)	Castor Oil	Stimulates bowel movements by irritating the gut	Constipation	Cramps, electrolyte imbalance
Laxatives (Osmotic)	Lactulose	Draws water into the bowel, softening stools	Constipation, hepatic encephalopathy	Bloating, diarrhea
Stool Softeners	Docusate	Increases water and fat penetration in stool	Constipation	Stomach cramps, diarrhea
Antiemetics (D2 Antagonist)	Metoclopramide	Blocks dopamine receptors in the gut and brain	Nausea, vomiting	Drowsiness, restlessness, fatigue
Antiemetics (H1 Antagonist)	Dimenhydrinate	Blocks H1 receptors, reducing histamine action in vomiting	Motion sickness, nausea	Drowsiness, dry mouth

Unit VII: Respiratory System

Drug Class	Drug Name	Mechanism of Action	Therapeutic Use	Adverse Effects
β2-Adrenergic Agonists	Albuterol	Stimulates β2 receptors, causing bronchodilation	Asthma, COPD	Tremors, tachycardia, nervousness
	Salmeterol	Long-acting β2 agonist, sustained bronchodilation	Asthma, COPD	Headache, throat irritation
Corticosteroids	Beclomethasone	Reduces inflammation in airways	Asthma	Oral thrush, hoarseness
	Fluticasone	Anti-inflammatory in lungs, decreases airway swelling	Asthma	Cough, sore throat
Leukotriene Antagonists	Montelukast	Blocks leukotriene receptors, reducing airway inflammation	Asthma, allergic rhinitis	Headache, abdominal pain
Xanthine Oxidase Inhibitors	Theophylline	Relaxes bronchial muscles, decreases inflammation	Chronic asthma, COPD	Nausea, tremors, insomnia
Antihistamines (H1 Blockers)	Diphenhydramine	Blocks histamine at H1 receptors	Allergic rhinitis, cough relief	Drowsiness, dry mouth
	Cetirizine	Non-sedating H1 antagonist	Allergic rhinitis, allergies	Dry mouth, mild drowsiness
Antitussives	Codeine	Suppresses cough reflex in CNS	Severe cough	Constipation, sedation
	Dextromethorphan	Decreases sensitivity of cough receptors	Cough	Dizziness, nausea