Block 3 Pharmacology Flashcards
Chlorpromazine - class
Dopamine receptor antagonist - phenothiazine based antipsychotic.
Chlorpromazine - MoA
Competitively binds D2 receptors in CTZ (5-HT, H and M), reduces activity of vomiting centre.
Chlorpromazine - uses
Nausea and vomiting.
Prochlorperazine used now.
Perphenazine - class
Dopamine receptor antagonist - antipsychotic phenothiazine
Perphenazine - MoA
Binds D1 and D2 receptors to inhibits their activity in CTZ and vomiting centre.
Perphenazine - uses
Severe nausea and vomiting.
15x more potent than chlorpromazine.
Metoclopramide - class
Dopamine receptor antagonist - benzoic acid derivative
Metoclopramide - MoA
Inhibits gastric smooth muscle relaxation produced by dopamine. Raises threshold in CTZ. Increases resting pressure of lower oesophageal sphincter so decreases reflux. Increases motility of stomach, oesophagus and intestines.
Metoclopramide - uses
GERD, nausea and vomiting.
Domperidone - class
Dopamine receptor antagonist - benzimidazole
Domperidone - MoA
Blocks dopamine receptos in CTZ, speeds up gastric peristalsis.
Domperidone - uses
Nausea and vomiting.
Aspirin - class
NSAID
Aspirin - MoA
Irreversibly binds COX and inhibits activity -> reduces prostaglandin production.
Analgesic, antipyretic and anti-inflammatory.
Aspirin - uses
Aches and pains.
Ibuprofen - class
NSAID
Ibuprofen - MoA
Irreversibly binds COX2 receptors -> reduces prostaglandin production.
Ibuprofen - uses
Aches and pains.
Side effects - GI bleed as reduced prostaglandins.
Naproxen - class
NSAID
Naproxen - MoA
Irreversibly binds COX receptors -> reduces prostaglandin production.
Naproxen - uses
RA, osteoarthritis, tendinitis.
Omeprazole - class
Proton-pump inhibitor
Omeprazole - MoA
Irreversibly binds H+/K+-ATPase enzyme in gastric parietal cell and blocks the release of H+ into gastric lumen.
72 hours with max effects at 2 hours.
Omeprazole - uses
Duodenal ulcers, GERD, heartburn
Esomeprazole - class
PPI
S isomer of omeprazole
Esomeprazole - MoA
Inhibits H+/K+-ATPase enzyme -> reduces gastric acid secretion.
Esomeprazole - uses
Peptic ulcers, GERD, heals erosive oesophagitis and eradication of H. pylori.
Cyclizine - class
Histamine receptor antagonist - piperazine derivative antihistamine.
Cyclizine - MoA
Blocks histamine receptors in CTZ, prevents overstimulation of histamine synapses in vomiting centre and reduces motion sickness.
Cyclizine - uses
Nausea, vomiting, dizziness and vertigo.
Cinnarizine - class
Histamine receptor antagonist and calcium channel blocker.
Cinnarizine - MoA
Competitive inhibitor of H1 receptors.
Blocks L-type and T-type voltage gated Ca2+ channels -> inhibits vascular smooth muscle contraction.
Cinnarizine - uses
Vertigo, motion sickness, nausea and vomiting.
Promethazine - class
Histamine receptor antagonist
Promethazine - MoA
Competitive antagonist of H1 receptors.
Central anticholinergic, sedative and local anaesthetic effects.
Promethazine - uses
Nausea, vomiting and allergic disorders
Ranitidine - class
Histamine receptor antagonist
Ranitidine - MoA
Competitive inhibitor of histamine at parietal cell H2 receptors. Suppresses normal secretion of gastric acid.
Inverse agonist as reduces effects of gastrin.
Ranitidine - uses
Peptic ulcers, dyspepsia and reflux oesophagitis.
Amoxicillin - class
Beta-lactam antibiotic
Amoxicillin - MoA
Binds and inactivates penicillin-binding protein 1A in bacterial cell wall -> inhibits cell wall synthesis -> cell lysis.
Amoxicillin - uses
Gram + and - bacteria in ear, nose, throat and skin.
H. pylori.
Used with clavulanic acid -> beta-lactamase inhibitor (prevents resistance).
Clarithromycin - class
Macrolide antibiotic
Clarithromycin - MoA
Binds 50S subunits of bacterial ribosome - blocks translocation of aminoacyl tTNA and polypeptide synthesis -> prevents growth of bacteria.
Clarithromycin - uses
Tonsilitis, acute maxillary sinusitis.
H. pylori
Hyoscine - class
Cholinergic receptor antagonist
Hyoscine - MoA
Competitive inhibitor of muscarinic cholinergic receptor. Stops nerve impulses between CTZ and vestibular system and PNS.
Hyoscine - uses
Colicky abdo pain, excessive salivation, IBS and motion sickness.
Magnesium trisilicate - class
Antacids
Magnesium trisilicate - MoA
Directly neutralises stomach acid, inhibits peptic enzymes.
Aluminium hydroxide delivers growth factors to injured mucosa, antacids promotes angiogenesis of injured mucosa.
Magnesium trisilicate - uses
Dyspepsia and oesophageal reflux.
Metronidazole - class
Nitroimidazole antibacterial and antiprotozoal.
DNA synthesis inhibitor.
Metronidazole - MoA
Binds to bacterial DNA and disrupts the helical structure and inhibits nucleic acid synthesis -> cell death.
Metronidazole - uses
Anaerobic and mixed infections. H. pylori, Crohn’s, diarrhoea.
Misoprostol - class
Prostaglandin agonist
Misoprostol - MoA
Binds prostaglandin receptor on parietal cells and reduces gastric acid secretion via reducing cAMP through Gi.
Increases bicarbonate production and increases thickness of mucus layer.
Misoprostol - uses
Ulcerations induced by NSAIDs
Ondansetron - class
5-HT3 receptor antagonist
Ondansetron - MoA
Inhibits 5-HT3 receptors to prevent stimulation of vomiting centre via CTZ and vagus nerve.
Ondansetron - uses
Nausea, vomiting associated with chemotherapy and radiation.
Atorvastatin - class
HMG-CoA reductase inhibitor
Atorvastatin - MoA
Competitive inhibitor of HMG-CoA reductase -> decreases plasma LDL levels due to increased hepatic uptake of LDL and inhibiting cholesterol synthesis.
Atorvastatin - uses
Prevention of arterial diseases.
Bezafibrate - class
Antilipemic agent - benzene derivative
Bezafibrate - MoA
Increased transcription of apoA1 and 5 -> increased hepatic LDL uptake. Activates triglyceride lipase and reduces cholesterol synthesis.
Bezafibrate - uses
Primary hyperlipidaemia.
Orlistat - class
Lipase inhibitor
Orlistat - MoA
Reversibly binds and blocks pancreatic and gastric lipase -> reduces breakdown of TAG -> undigested TAG excreted.
Orlistat - uses
Obesity.
Used with fat-soluble vitamins.
Thalidomide - class
Hypnotic, antiemetic.
Thalidomide - MoA
Immunosuppressive and anti-angiogenic activity. Inhibits release of TNFalpha from monocytes and modulates cytokine action.
Teratogenic activity.
Thalidomide - uses
Morning sickness (caused embryological deformities), multiple myeloma and leprosy.