Opioid Past Paper PDF

 Introduction The opium poppy is the source of crude opium. Morphine was first isolated in 1803 by Sertürner. Morphine,the prototypic opioid agonist  Opioid receptors I These receptors are abundant in CNS and GIT. The Opioid receptors are...

 Introduction The opium poppy is the source of crude opium. Morphine was first isolated in 1803 by Sertürner. Morphine,the prototypic opioid agonist  Opioid receptors I These receptors are abundant in CNS and GIT. The Opioid receptors are: Mu (µ) Kappa (K) it Delta (δ) a setS Endogenous peptides which are released and combine with bit these receptors are 9  Enkephalin Wifi I 9s Iii I.fi  Endorphin  Dynorphin a iiti aio i Exogenously administered Opiates also combine with these receptors for M1 patients Morphing  Classification WITH MN Gg g qq.gg Respiratory sells oppresion pethidine 5  Nausea Vomiting CNS Damie Pharmacological Effects A. Acute effects calming Dom cough 1. CNS :Analgesia, Sedation , Euphoria, Respiratory depression, Antitussive action, Nausea ,Vomiting, Miosis. 2. CVS. bi eusile like head of pen if adf.fm 3. Resp System. 4. GIT: Smooth muscle and Sphincters. cash Is 5. Histamine release. 6. Action on Uterus. B. Chronic effects 1.Tolerance 2.Dependence 3.Suppression of secretion of Gonadal hormones soaks Dopamine t.si Euphoria Morphine produces a powerful sense of contentment and sense of well- being. It is this effect which makes it an important drug of abuse. PDA Behavioral and pharmacological data point to the role of dopaminergic pathways, particularly involving the nucleus accumbens (NAcc), in drug- induced reward. There is ample evidence for interactions between opioids and dopamine in mediating opioid-induced reward Depression of cough reflex  Both morphine and codeine - Antitussive properties  Miosis The pinpoint pupil - Characteristic of morphine use. Morphine excites the nucleus of the Oculomotor nerve, no tolerance develops. FINE 1158M aid Emesis Morphine directly stimulates the Chemoreceptor trigger zone which causes vomiting, tolerance develop to this effect. minima.edu ldQ  5'54 1 06 Cardiovascular System  Morphine has no major effects on the blood pressure or heart rate. jawed it  Except at large doses, hypotension and bradycardia may occur. His inns BV to dilate Histamine release t.es jbk is 191  Morphine releases histamine from mast cells, causing Urticaria.  Because it can cause Bronchoconstriction - Asthmatics should receive the drug with care. Asthma s oMokhain mI and a p.IM W.I.sk I Asthma attaik Gastrointestinal tract M  Morphine relieves Diarrhea and Dysentery by decreasing the motility and increasing the tone of the intestinal circular smooth muscle.  Morphine produces constipation, with no tolerance. Morphine increases the tone of all Sphincters. Not to be used for relief of pain in biliary colic. Increases the contraction of detrusor muscle of urinary bladder but increases the tone of sphincter – Urinary retention. Construction of sphincter muscle Pharmacological action of morphine Analgesia Sedation Euphoria Respiratory depression Itching Morphine I'M Mu opioid receptor present in brain  Tolerance Marked tolerance develop to all the effects except miosis and constipation, mainly due to pharmacodynamics, cells adapt to the drugs action.  An addict need progressively higher dose.  Comparison of Morphine and Pethidine Features Morphine Pethidine Source Natural Synthetic Oral absorption Reduced by First hepatic Well absorbed – More pass – Less effective effective Orally Orally 1 Anti – Cholinergic action Nil Seen Use in AMI with Preferred Not Preferred Pulmonary edema Antitussive & GIT Effect Seen Nil. not effective in diarrhea or cough  Antagonist of morphine Antidote for Antagonist of morphine: Naloxone & Morphinetoxicity Naltrexone wordy NALOXONE is the drug of choice for narcotic overdose.