On October 23rd, 2014, we updated our
By continuing to use LinkedIn’s SlideShare service, you agree to the revised terms, so please take a few minutes to review them.
PHARMACOLOGICAL ACTIONS CNS Stimulates many medullary centres. Vagal, respiratory and vasomotor. Anti-motion sickness property. High dose cause Restlessness Disorientation Hallucinations Respiratory depression Coma. 11/8/2010 12
CVS primarily in modifications of the heart rate: very low dose, it can give a slight cardiac slowing therapeutic dose there is generally cardiac acceleration It does not have vascular effects since there is no parasympathetic tonus on the vessels but it inhibits vasodilatation caused by an intravenous injection of acetylcholine. It does not induce modifications of arterial pressure in spite of increased cardiac rate. in very high or toxic dose, it induces a fall of the arterial pressure by depression of the vasomotor centers 11/8/2010 13
PHARMACOLOGICAL ACTIONS EYS Mydriasis Cycloplegia Photophobia. SMOOTH MUSCLES Relaxation M3 Blokade Tone is reduced Constipation Bronchodilation (asthma) 11/8/2010 14
PHARMACOLOGICAL ACTIONS GLANDS Sweat Bronchial secretions Lacrinal secretions. Acid, pepsin and mucus in stomach. BODY TEMPERATURE Inhibition of sweating Temperature regulatory centre in hypothalamus Atropine fever 11/8/2010 15
Sensitivity 11/8/2010 16
TROPICAMIDE Blocks the response of sphincter muscle of iris and ciliary muscles to cholinergic stimulation thus causing mydriasis. Stronger preparation also paralyzes accommodation. Acts within 15-30 m and duration is 3-8 h. typically used during eye examinations such as the dilated fundus examination, but it may also be used before or after eye surgery.
DICYCLOMINE It is a smooth muscle relaxant. Irritable Bowel Syndrome (also known as spastic colon). It relieves muscle spasms and cramping in the gastrointestinal tract by blocking the activity of acetylcholine on cholinergic (muscarinic) receptors on the surface of muscle cells.
HEXAMETHONIUM Ganglionic blocker N receptor antagonist, acts in autonomic ganglia. Does not have any effect on muscarinic Ach receptors. Acts at receptors at neuromuscular junction responsible for skeletal muscle motor response.
USES Antisecretory Preanaesthtic The main reasons for using anticholinergic drugs were drying of secretions and protection against vagal over activity. Blocks responses to vegal refluxes induced by sergical manipulations of visceral organs. Peptic ulcer Pulmonary embolism 11/8/2010 24
Antispasmodic Spactic constipation Nervous and drug induced diarrhoea. Asthama, COPD Cardiac vagolytic Bradycardia Central actions Parkinsonism Motion sickness 11/8/2010 25
References Tripathi KD. Anticholinergic drugs.In Essentials of medical Pharmacology. 5th ed. JP Brothers Medical publishers (P) Ltd: New Delhi; 2003. pp. 93-102. Katzung, Bertram.G, Basic and clinical pharmacology.10th ed. Mc Graw Hill. USA(NY); 2006. pp. 482-9. Goodman & Gilman’s, The Pharmacological Basis Of Therapeutics. 11th ed. Mc Graw Hill. USA(NY); 2006. pp. 121-9. 11/8/2010 26