What is a potential side effect of systemic antacid use?
What type of drugs are Neurokinin1 (NK-1) receptor antagonists?
What does H1 receptor antagonists treat?
Nausea and Vomiting
How do bulking agents work?
They absorb water > increase in size > stimulates movement
How does hyoscine butylbromide act as a anti-diarrhoeal?
Muscarinic receptor antagonists therefore decrease gut motility
What is misoprostol?
A synthetic prostaglandin E2 analogue
What effect do cannabinoids have?
What is the problem with lipid paraffin?
Takes vitamins with it
Leaks out of the anus
Can cause pneumonia is aspirated
What is hyoscine hydrobromide?
A muscarinic receptor antagonist used for motion sickness
What drugs are used for nausea associated with migraine?
How long is it advisible to stay on proton pump inhibitors for ulcers to heal?
Metoclopramide has another effect apart from being a anti-emetic, what is it?
Increase stomach and upper small intestine motility
What type of drug is Esomeprazole?
Proton pump inhibitor
What drugs target the chemoreceptor trigger zone?
Dopamine D2 receptor antagonists - Metoclopramide and Prochlorperazine
How does metoclopradine increase gut motility
Block dopamine's inhibition of ACh release (being a dopamine D2 receptor antagonists)
Agonist of 5HT4 receptor > increase ACh release
Note: ACh acts on gastric smooth muscle to increase motility
Name a Serotonin 5HT3-Receptor Antagonists
What are Ranitidine and Cimetidine?
H2 receptor antagonists
What type of drug is Hyoscine butylbromide?
At what point do extrapyramidal side effects of certain anti-emetic drugs become irreversible?
When tardic dyskinesia develops
Parkinson's like symptoms or extrapyramadial side effects are cause by which class of drugs?
Dopamine D2 antagonists
What are Serotonin 5HT3-Receptor Antagonists used for?
Extremely potent anti-emetics
How does Rantidine work?
It is a H2 receptor antagonist
It blocks histamine stimulation of acid secretion in parietal cells
What are the side effects of H2 receptor antagonists?
No major side effects in current ones
Cimetidine causes gynecomastia in males
What are some causes of constipation?
Drugs (esp opioids)
Inadequate dietary fibre/water
Ignoring the "call" to go
Which opioid is used as an anti-diarrhoeal? Why?
Doesn't cross the BBB therefore doesn't cause the CNS effects
Which class of drug was classically thought to danger the colon with long term however has recently been found not to?
What type of drug is liquid paraffin?
What are the most used laxative currently?
What is the main side effect of Promethazine and other drugs of its class?
What are H2 receptor antagonists indicated for?
Name a bulking agent
How must antacids be administered to allow for ulcer healing?
Constant use - their action is short lived
Name a detergent laxative and their mechanism of action
Increase water content of faeces
What type of drug is bisacodyl?
Name the two important inputs to the vomiting centre due to their being targeted by anti-emetic drugs
Chemoreceptor trigger zone
When are proton pump inhibitors indicated?
Name a prostaglandin E2 analogue
Name some important antacids
Sodium bicarbonate (systemic)
What side effects do all muscarinic receptor antagonists have?
Anti-cholinergic effects = decrease SLUD therefore:
What are dopamine D2 receptor antagonists indicated for?
Nausea and vomiting
Name two stimulant/irritant laxatives
What are emetic drugs used for?
Induce vomiting for the removal of ingested poisons/toxins
Name an important spasmolytic drug
How do irritant laxatives work?
Directly stimulate colonic myenter nerve plexus
What do spasmolytic drugs do?
Prevent smooth muscle spasm to reduce their associated pain
What specific conditions can metoclopramide be used for?
Reduced motility to neurodamage in diabetes
What type of drug is hyoscine hydrobromide?
Muscarinic receptor antagonist
What is the problem with prostaglandin E2 analogues?
They cause uterus contraction > abortions
What are two proton pump inhibitors?
What class of drugs are generally indicated for nausea due to vestibular apparatus problems?
H1 receptor antagonists
T/F Hyoscine hydrobromide crosses the BBB
Name a osmotic laxative and their mode of action
Increase water content of faeces
What is Ranitidine?
A H2 receptor antagonist
What type of drug is prochlorperazine?
A D2 dopamine receptor antagonist
What does Simethicone do?
Reduces the surface tension of small flatus bubbles thereby facilitating their aggregation into larger bubbles and passage out of the anus
What are prostaglandin E2 analogues used for?
Reduce gastric acid secretion
Increase blood flow
Increase mucous secretion
How do proton pump inhibitors block acid secretion?
Irreversibly bind to proton pumps
What type of drug is docusate?
What does metaclopramide treat?
Nausea and vomiting
What came first, antacids or H2 receptor antagonists?
How do cytoprotective agents work?
They coat ulcer to protect it
What must opioids be given with?
Name two dopamine D2 receptor antagonists
Name a H1 receptor antagonist
What type of drugs typically cause constipation?
Muscarinic receptor antagonists
What is bismuth chelate
A cytoprotective agent
What is the problem with cytoprotect agents?
They blacken the teeth, tongue and faeces
When shouldn't Brann or drugs from its class be used?
When underlying motility is slow as it contributes to constipation
Apart from being a dopamine D2 receptor antagonists, what other effects does metoclopramide have?
5HT3 receptor antagonist
5HT4 receptor agonist
In what setting are dopamine D2 receptor antagonists generally used?
Hospitals to relieve the symptoms associated with chemo/radio therapy and post anaesthetics
Which dopamine D2 receptor antagonists cause extrapyramidal side effects with long term use?
What is Promethazine?
A H1 receptor antagonist
How is Senna usually taken?
With docusate for opioid induced constipation
T/F Neurokinin-1 receptor antagonists are used on their own
False, they are used with Dopamine D2 receptor antagonists
What do dopamine D2 receptor antagonists treat?
Are extrapyramadial side effect reversible?
Yes if the drugs hasn't been used for too long
What is hyoscine hydrobromide indicated for?
How does Ondansetron work as an anti-emetic?
Blocks 5HT3 receptors in the CNS and local vagal sensory fibres