Pharmacology Flashcards
Give 5 types of Anti-Emetic Drugs?
Antihistamines Antimuscarinics 5-HT3 receptor antagonists Dopamine receptor antagonists Neurokini-1 receptor antagonists
what receptor do antihistamines work on?
and what effect do they have?
H1 receptor
they antagonise it
they are indicated for motion sickness
give an example of an Antihistamine?
Cyclizine
Give an example of an Antimuscarinic?
Scopolaimine
give an example of 5-HT receptor antagonist
Ondansetron
what is the main side effect for Antihistamine?
Sedation (act on H1 receptors on the brain)
when are antihistamines or antimuscarinics indicated?
motion sickness
what are the main side effects of antimuscarinics?
dry mouth, tachycardia and constipation
what part of the brain causes vomiting?
emetic centre in the brain stem
give an example of a dopamine receptor antagonist
Chlorpromazine
give an example of a Neurokinin-1 receptor antagonist
Foraprepitant
what type of drugs are antidiarrhoeal drugs?
opiates
give a Dopamine receptor antagonists example
chloropromazine
what receptors do dopamine receptor antagonists act on?
D2 receptors in the chemoreceptor trigger zone of the medulla
what is the difference between Domperidone and other Dopamine receptor antagonists?
domperidone does not cross the blood brain barrier and so only has peripheral effects
Neurokinin 1 receptor antagonists example?
Foraprepitant
what receptor do Neurokinin 1 receptor antagonists act on?
and what do they block?
NK receptors in the Gut and Chemoreceptor trigger zone in the medulla
and they block substance P
what type of drugs are antidiarrhoeal drugs?
opiates
what drug is indicated for motion sickness?
cyclizine
it is an antihistamine
give an example of an Antimuscarinic
Scopolaimine
give an example of a 5-HT3 receptor antagonist
Ondansetron
what is the main effect of antihistamines?
sedation
what are PPIs?
Proton Pump Inhibitors
give an example of a PPI?
Lansoprazole, omeprazole
what are PPIs used for?
benign gastric acid ulceration, NSAID associated gastro-oesophageal reflux disease and Zollinger-Ellison syndrome
what is Zollinger-Ellison Syndrome?
condition where the body produces excess gastric acid
what is the negative effect of PPI’s?
increase stomach pH, so reduce defences against infection
Action of Histamine H2 receptor antagonists example?
Ranitidine, Cimetidine
what does Histamine H2 receptor antagonists do?
block H2 receptors and eventually reduces HCl secretion
what causes Peptic Ulcer?
H.pylori infection, causing destruction of mucous layer protection, as HCO3 decreases due to destruction of mucous cells, pH decreases, so there is an increase in Gastric acid causing ulceration
Treatment for Peptic Ulcers
PPI- stop secretion of gastric acid
Antibiotics (clarythryomycin and amoxicillin/ metronidazole)