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Similar to anticholinergic sysytem and drugs .pptx
anticholinergic sysytem and drugs .pptx
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- 2. MUSCARINIC RECEPTORANTAGONISTS/ ATROPINIC/ PARASYMPATHOLYTIC/ OTHER NAMES
- 3. Drugs thatblock or inhibit the actions of acetylcholine (ACh) in the parasympathetic nervous system (PSNS) Also called cholinergic blocking agents or parasympatholytics Often referred to as anticholinergics or antimuscarinics
- 4. Competitive antagonists Compete with acetylcholine Block acetylcholine at the muscarinic receptors in the PSNS Reversible blockade of acetylcholine at muscarinic receptors by competitive binding Once these drugs bind to receptors, they inhibit nerve transmission at these receptors. Mechanism of Action
- 5. Nicotinic receptorantagonists also block certain actions of Ach Referred as GANGLION BLOCKERS/ NEUROMUSCULAR BLOCKERS
- 7. Prototype antimuscarinicdrug - derived from Atropa belladonna (deadly nightshade) and Datura stramonium (thorn apple) History: during the Italian renaissance dilated pupils were considered desirable plant extracts were used as cosmetic eye drops hence the name belladonna or "beautiful lady" in Italian Atropine
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- 10. Tachycardia Vascular– no (direct) effect – except, dilate cutaneous vessels (red as a beet) – block hypotensive effect of muscarinic agonists Actions Cardiovascular effects-
- 11. At normaldoses atropine stimulates medullary centers At higher doses produce excitement, agitation, hallucinations and coma. Depresses vestibular excitation and has anti motion sickness properties Supresses tremor and rigidity of parkinsonism by blocking cholinergic overactivity in basal ganglia. Actions On CNS
- 12. Dilated pupils(mydriasis) Blocks muscarinic innervations on the circular muscles (Mydriasis) and relaxes cilairy muscles (Cycloplegia) worsens glaucoma Actions on Eye
- 13. Relax smoothmuscles of GI tract Decrease intestinal and gastric secretions Decrease motility and peristalsis antispasmodic effect Sphincter contraction Gastrointestinal
- 14. Decreases bronchialsecretion (used as preanesthetic Medication,COPD) Dilated bronchial airways (used for treatment of Asthma) Actions Respiratory system
- 15. Relaxes detrusormuscle Increased constriction of internal sphincter Result: urinary retention Relaxation of smooth muscles of ureters contraindicated for prostate hypertrophy patients. Genitourinary
- 16. Salivary secretion(Dry mouth) Decreases Gastric Acid (used for Peptic Ulcer ) Sweating Dry skin Fever in infants and children. Dec. Bronchial Secretion (used for COPD) Glandular
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- 19. Parkinson’s disease– Benztropine, Trihexyphenidyl ,biperdine Motion Sickness (Scopolamine/hyoscine) Drug-induced extrapyramidal reactions(due to antipsychotics) Central Nervous System
- 20. Atropine isused to increase heart rate in symptomatic bradycardias. Sinus node dysfunction Symptomatic second-degree heart block Sinus or nodal bradycardia (due to myocardial infarction) CVS
- 21. Chronic bronchitis Asthma Exercise-induced bronchospasms Chronic obstructive pulmonary disease - Ipratropium , Tiotropium Respiratory system-
- 22. Peptic Ulcer:Pirenzepine ,telenzepine As antispasmodic :Dicyclomine Irritable bowel disease: Propantheline GI hypersecretory states Gastrointestinal
- 23. Antispasmodic effectsseen in overactive bladder and in urinary incontinence - Oxybutynin Detrusor hyper-reflexia Enuresis -Increase bladder capacity -Decrease bladder pressure Urge incontinence-Darifenacine,Solufenacine Urologic disorders
- 24. Homatropine,tropicamide – Accuratemeasurement of refractive error in uncooperative patients (e.g, children) Examination of retina (Mydriasis) Opthalmological Disorders-
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- 27. Anticholinergic overdosesyndrome (Belladona poisoning- consumption of seeds or berries of belladona or dhatura plant) characterized by: Hyperthermia, delirium, dry mouth, tacycardia, ileus, urinary retention. Seizures, coma and respiratory arrest may occur. Treatment – Gastric lavage with tannic acid, cold sponging or ice bags, Physostigmine s.c. or i.v., diazepam to control convulsions. Toxicity of Anticholinergics
- 28. Glaucoma Prostatichypertrophy Urinary tract obstruction Gastrointestinal tract obstruction Infectious diarrhea Reflux esophagitis Tachyarrhythmias Angina Hyperthyroidism Pregnancy Contraindications
- 29. Atropine Prototype. Antidote in OP Poisoning. Ipratropium Useful in rhinorrhea. Also excellent bronchodilator. Individual Drugs
- 30. Scopolamine DepressesCNS and causes amnesia, drowsiness, euphoria, relaxation and sleep. Motion sickness. Given parenterally, orally and transdermally. Benztropine Temporary use in Parkinson’s disease. Useful for dystonic reactions caused by antipsychotics.
- 31. Trihexyphenidyl Alsoused for treating EPS by some antipsychotics. Contraindicated in glaucoma. Flavoxate relieves dysuria, urgency, frequency, and pain with GU infections Oxybutynin has direct antispasmodic effects on smooth muscle and anticholinergic effects. Decreases frequency of voiding.
- 33. DRUGS ACTING ONAUTONOMIC GANGLIA
- 34. Acetylcholine isthe primary exitatory neurotransmitter in both sympathetic and parasympathetic ganglia both Sympathetic and parasympathetic ganglia stimulated No therapeutic application
- 35. Principal alkaloidin tobacco Acts as an agonist on both Nn and Nm subtypes of nicotinic cholinergic receptors Only use- short term replacement therapy in tobacco abstinent subjects. NICOTINE
- 36. Wish toquit but fail due to nicotine dependance Goals for such pharmacotherapy- to reduce craving Suppress physical withdrawl symptoms like anxiety, depressed mood ,irritability,inability to concentrate,tremors Treatment of smoking cessation
- 37. NICOTINE REPLACEMENT PARTIAL AGONISTS OF α4β2 NRs-varenicline ANTIDEPRESSANTS- Bupropion Drugs
- 38. HEXAMETHONIUM PENTOLINIUM MECAMYLAMINE PEMPIDINE GANGLIONIC BLOCKING AGENTS
- 39. Used earlierfor HTN and peptic ulcer Totally replaced now Produces intolerable side effects