Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pharmacology > Gastrointestinal > Flashcards

Gastrointestinal Flashcards

1
Q

What is a Proton Pump Inhibitor and how do they work?

A

Proton pump inhibitors (PPIs) reduce gastric acid secretion. ‘proton pump’ responsible for secreting H+.

Drug examples: Omeprazole, Lansoprazole, Pantoprazole

MOA: They act by irreversibly inhibiting H+/K+-ATPase in gastric parietal cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What other drugs do PPI’s work (indication) with?

A
  1. Prevent ulcers, known with NSAID association
  2. Symptom relief with Gastro-oesophageal-reflux-disease (GORD) and dyspepsia
  3. Eradication of helicobacter pylori infection, in combination with antibiotics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Adverse effects of PPI’s?

A
  1. Gastrointestinal disturbances
  2. Headaches
  3. May reduce patients host defect against infection
  4. Hypomagnesia (Lead to tetany and ventricular arrhythmia)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Contraindication of PPI?

A
  • Potentially mask gastro cancer symptoms. Should be stopped 2 weeks before endoscopy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Cautions of PPI?

A
  • Increase the risk of fractures
  • Osteoporosis
  • Hypomagnesaemia
  • Reduce anti-platelet effect (Warning)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Interactions of PPI?

A
  1. Antiplatelet effect of ▴clopidogrel by decreasing its activation by cytochrome P450 enzymes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Monitoring of PPI?

A
  • Response to PPI should be monitored in response to ulcer treatment
  • Prolonged use >1yr monitor for hypomagnesaemia.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Patient education for PPI?

A
  1. Explain it reduces acid in stomach
  2. Explain clearly H.pylori eradication treatment of 7 days
  3. Oral preparations can be taken with food or on an empty stomach. They are best taken in the morning
  4. Evidence of healing will be known by symptoms relief or endoscopy
  5. Any swallowing problems or weight loss report immediately.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is H2 receptor antagonist and how do they work?

A

Histamine H2-receptor antagonists (‘H2-blockers’) reduce gastric acid secretion.

Drug Examples: Ranitidine

MOA:
1. Paracrine cells release histamine and bind to H2 receptors

  1. Second messenger system activates proton pump
  2. Using Histamine H2 receptors blocker reduces acid secretion although cannot fully suppress acid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What other drugs do H2 antagonist work (indication) with?

A
  1. Peptic ulcer disease Treat and prevent duodenal, gastric and NSAIDs ulcers.
  2. Gastro-oesophageal reflux disease (GORD) and dyspepsia relief of symptoms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What other drugs do H2 receptor antagonist work (indication) with?

A
  1. Peptic ulcer disease Treat and prevent duodenal, gastric and NSAIDs ulcers.
  2. Gastro-oesophageal reflux disease (GORD) and dyspepsia relief of symptoms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Adverse effects of H2 receptor antagonist?

A
  1. Bowel disturbance (diarrhoea or, less often, constipation)
  2. Headache and dizziness.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Contraindication of H2 receptor antagonist ?

A
  1. Should not be prescribed in symptomatic patients as it can mask gastro malignancy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Cautions of H2 receptor antagonist?

A
  1. renal impairment patients
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Interactions of H2 receptor antagonist ?

A

Ranitidine has no major drug interactions.
Azole antifungals
Protease inhibitors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Monitoring of H2 receptor antagonist?

A

Treatment of peptic ulcer disease, repeat endoscopy may be necessary in some cases to confirm healing

Symptomatic treatment of dyspepsia and GORD, the patient’s symptoms are the best guide to the effect of therapy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Patient education for H2 antagonist?

A

Can be purchased over the counter, however be used for short term 1-2 weeks. Prescription needed for more than 2 weeks.

Can be taken before, during or after food

Helps reduce acid and symptoms

Report any alarming symptoms like weight loss, swallowing difficulty

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is a antacids and how do they work?

A

These drugs are most often taken as compound preparations containing an alginate with one or more antacids, such as sodium bicarbonate, calcium carbonate, magnesium or aluminium salts.

Drug examples: Gaviscon®, Peptac®

MOA:
Antacids work by buffering stomach acids.

Alginates act to increase the viscosity of the stomach contents, which reduces the reflux of stomach acid into the oesophagus.

They form a ‘raft’, which separates the gastric contents from the gastro-oesophageal junction to prevent mucosal damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What other drugs do antacids work (indication) with?

A
  1. Gastro-oesophageal reflux disease (GORD): for symptomatic relief of heartburn.
  2. Dyspepsia: for short-term relief of indigestion.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What other drugs do antacids work (indication) with?

A
  1. Gastro-oesophageal reflux disease (GORD): for symptomatic relief of heartburn.
  2. Dyspepsia: for short-term relief of indigestion.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Adverse effects of antacids ?

A
  1. Magnesium salts can cause diarrhoea

2. Aluminium salts can cause constipation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Adverse effects of antacids ?

A
  1. Magnesium salts can cause diarrhoea

2. Aluminium salts can cause constipation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Contraindication of Antacids?

A

Avoid hypersensitive to any of the ingredients or excipients

Hepatic impairment

Avoid antacids containing large amounts of sodium if the person has fluid retention.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Cautions of Antacids ?

A
  • Thickened milk preparations as they can lead to excessively thick stomach contents
  • Patients with evidence of iron deficiency because the normal absorption of iron is enhanced by gastric acidity
  • Renal failure patients caution using sodium + potassium preparations
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Interactions of Antacids?

A
  • Antacids can reduce serum concentrations of many drugs, so doses should be separated by 2 hours.
- Examples of these drugs: 
ACEinhibitors
Cephalosporins
Ciprofloxacin and Tetracyclines
Bisphosphonates
Digoxin
Levothyroxine and proton pump inhibitors (PPIs)

Antacids can increase the excretion of aspirin and lithium due to alkalinity of urine.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Monitoring of Antacids?

A
  • If there are persistent symptoms or ‘red flags’, such as bleeding, vomiting, dysphagia and weight loss, further investigation and specialist review are required.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Patient education for Antacids?

A
  1. Medicine should relieve the symptoms of heartburn and acid indigestion within about 20 minutes and for several hours afterwards.
  2. Eating smaller meals more often, identifying and avoiding food and drink triggers, stopping smoking and raising the head of the bed.
  3. Advise patients to take compound alginates after mealtimes and before bed. Advise them to leave a gap of at least 2 hours between these medicines and other drugs that they may interact
  4. Compound alginates are available as oral suspensions or chewable tablets
28
Q

What is a Osmotic Laxative and how do they work?

A

These medicines are based on osmotically active substances (sugars or alcohols) that are not digested or absorbed, and which therefore remain in the gut lumen.

Drug examples: Lactulose, Macrogol, Phosphate enema

MOA: They hold water in the stool, maintaining its volume and stimulating peristalsis.

Lactulose, in particular, also reduces ammonia absorption. It increases gut transient rate, acidify the stools, inhibits proliferation of ammonia producing bacteria. This helps in hepatic encephalopathy

29
Q

What other drugs do Osmotic Laxative work (indication) with?

A
  1. Constipation and faecal impaction.
  2. Bowel preparation prior to surgery or endoscopy.
  3. Hepatic encephalopathy.
30
Q

Adverse effects of Osmotic laxatives ?

A
  • Flatulence
  • Abdominal cramps
  • Nausea
  • Diarrhoea is a possible complication
  • Phosphate enemas can cause local irritation and electrolyte disturbances.
31
Q

Contraindication of Osmotic laxaive ?

A
  • Intestinal obstruction (Risk of perforation)
  • Paralytic ileus (Slowing of intestinal movement)
  • Toxic megacolon.
  • History of hypersensitivity to peanuts (arachis oil enema
32
Q

Cautions of Osmotic Laxative ?

A
  • Heart failure
  • Ascites
  • Electrolyte disturbances
  • Lactulose intolerance
  • History of prolonged use due to risk of electrolyte balance
  • Warfarin effect may be slightly increased
33
Q

Interactions of Osmotic Laxative?

A
  • Warfarin effect may increase
34
Q

Monitoring of Osmotic laxative?

A
  • Bristol stool charts useful to monitor treatment effect

- Monitor electrolytes

35
Q

Patient education for Osmotic laxatives?

A
  • Offering treatment that will help soften the stool
  • Osmotic laxatives can be taken with or without food. In order to work, patients need to drink at least 6-8 glasses a day.
  • Enemas are administered with the patient lying on their side, as for a rectal examination. Patients stay in this position until ready to open bowels
  • If they are regularly passing more than two or three soft stools per day, the dose should be reduced or the laxative stopped (unless it is being used for hepatic encephalopathy).
36
Q

What is a Stimulant laxative and how do they work?

A

Stimulant (also known as irritant or contact) laxatives

Example drugs: Senna, Bisacodyl, Glycerol suppositories, Docusate sodium

MOA: Laxatives increase water and electrolyte secretion from the colonic mucosa, thereby increasing the volume of colonic content and stimulating peristalsis.

Senna: Bacterial metabolism of senna in the intestine produces metabolites that have a direct action on the enteric nervous system, stimulating peristalsis

Rectal administration of stimulant laxatives, such as glycerol suppositories, provokes a similar but more localised effect and can be useful to treat faecal impaction.

37
Q

What other drugs do Stimulant laxative work (indication) with?

A
  1. Constipation

2. Suppositories for faecal impaction

38
Q

Adverse effects of Stimulant laxative ?

A
  • Abdominal pain
  • Cramping
  • Diarrhoea
  • Melanosis coli (reversible pigmentation of the intestinal wall)
39
Q

Contraindication of Stimulant laxative?

A
  • Intestinal obstruction
  • Risk of perforation
  • Paralytic ileus
  • Toxic megacolon
  • Crohn’s disease or ulcerative colitis
40
Q

Cautions of Stimulant laxative?

A
  • Haemorroids
  • Anal fissures
  • Hypokalaemia
  • Eating disorders
41
Q

Interactions of Stimulant laxatives?

A

No known interactions

42
Q

Monitoring of Stimulant laxative?

A

Inpatients: a stool chart is useful to monitor the effects of treatment.

43
Q

Patient education for stimulant laxative?

A

Patient info: helps as a stool softner
Aim for 6–8 glasses of liquid per day.
May take a few hours till the effect works
If passing more than 3 stools a day, stop treatment
Side effects such as abdominal cramp, faltuance can occur
Usually oral mediciation unless faecal impaction rectal stimulants can be used

44
Q

What is a Bulk-forming Laxative and how do they work?

A
  • These agents retain fluid in the stool and increase stool weight and consistency.

MOA: Psyllium, methylcellulose

Bulk-forming laxatives are not digested but absorb liquid in the intestines and swell to form a soft, bulky stool. The bowel is then stimulated normally by the presence of the bulky mass.

45
Q

What other drugs do bulk-forming laxatives work (indication) with?

A

By increasing intestinal motility, can potentially decrease transit time of concomitantly administered oral drugs and thereby decrease their absorption.

Administer ≥2–3 hours before or after other medications.

46
Q

Adverse effect of bulk-forming laxative?

A

Changes in bowel habits

Bloating

47
Q

Contraindication of Bulk-forming laxatives?

A
  • Hypersensitivity to bulk forming laxatives
  • Abdominal pain, nausea, vomiting
  • Partial obstruction of the bowel
  • Experienced sudden change in bowel habits >2 weeks
48
Q

Cautions of Bulk-forming laxatives?

A
  • Bowel obstruction
  • Psyillium hypersensitivity
  • Milk hypersensitivity
49
Q

Monitoring of Bulk-forming laxative?

A
  • Bristol stool chart
50
Q

Patient education for bulk forming laxative?

A
  • Same as the rest above
51
Q

What is Metoclopramide and how do they work?

A

Metoclopramide is an anti-sickness medicine (known as an antiemetic). It’s used to help stop you feeling or being sick (nausea or vomiting)

Drug examples: Metoclopramide, Domperidone

MOA: D2 receptor is the main receptor in the chemoreceptor trigger zone (CTZ), which is the area responsible for sensing emetogenic substances in the blood. D2-receptor antagonists are therefore effective in nausea and vomiting caused by CTZ stimulation (e.g. by emetogenic drugs)

D2-receptor antagonists therefore have a prokinetic effect, promoting gastric emptying

Dopamine is a neurotransmitter promoting relaxation of the stomach, inhibiting gastrointestinal duodenal coordination

52
Q

What other drugs do Metoclopramide work (indication) with?

A
  • Nausea
  • Vomiting
  • Reduced gut motility
53
Q

Adverse effects of Metoclopramide?

A
  • Diarrhoea
  • Extrapyramidal syndromes movement abnormalities
  • Acute dystonic reaction such as an oculogyric crisis due to same mechanisim of antipsycotics.
  • Domperidone is associated with an increased risk of QT-interval prolongation and arrhythmias.
54
Q

Contraindication of Metoclopramide?

A
  • Avoided in neonates
  • Cardiac conduction abnormalities
  • Perforation
  • Avoided in intestinal obstruction and perforation
  • Parkinsons disease as it antagonise the effects of dopaminergic agents
55
Q

Caution of Metoclopramide?

A
  • Extrapyramidal effects, metoclopramide should be prescribed for no more than 5 days
  • Young adults who are at increased risk of adverse effects
  • Children
  • Parkinsons disease
  • Domperidone may be used as it does not cross the blood–brain barrier.
56
Q

Interactions of Metoclopramide (Antiemetic) ?

A
  1. Risk of extrapyramidal side effects is increased when metoclopramide is prescribed with ▴antipsychotics
  2. It should not be combined with ✗dopaminergic agents for Parkinson’s disease, as it will antagonise their effects.
  3. Domperidone should not be prescribed alongside other drugs that prolong the QT interval, such as antipsychotics, quinine, SSRI’s
  4. Those which inhibit cytochrome P450 (CYP) inhibitors (e.g. amiodarone, diltiazem, macrolides
57
Q

Monitoring of Metoclopramide?

A
  • Prolonged use is not recommended
  • If unavoidable, you should monitor the patient for extrapyramidal features, as these may be subtle
  • An increased tendency to falls
58
Q

Patient education for Metoclopramide ?

A
  • Starting dose for both metoclopramide and domperidone is 10 mg 8-hrly. Metoclopramide can be prescribed for IM or IV injection; the dose remains the same.
  • Neither drug should be prescribed for more than a week (5 days for metoclopramide)
  • Antisickness medication. Some patients experience the side effects, such as movement abnormalities, if noticed they need to stop treatment.
59
Q

What is Loperamide and how do they work?

A

It is an antimotility drug, pharmacologically similar to pethidine

Drug examples: Loperamide, codeine phosphate

MOA: It is an agonist of the opioid µ-receptors in the gut. It increases non propulsive contractions in the gut smooth muscles and reduces propulsive (peristaltic) contractions

Transit of bowel contents is slowed and anal sphincter tone is increased. Slower gut transit also allows more time for water absorption, which (in the context of watery diarrhoea, creating harder stools

Other opioids (e.g. codeine phosphate) have similar effects

60
Q

What other indications does Loperamide work with?

A
  • Diarrhoea

- Viral gastroenteritis

61
Q

Adverse effects of Loperamide?

A
  • GI effects
  • Constipation
  • Abdominal cramping
  • Flatuance
  • Risk of opioid toxitity with codine
62
Q

Contraindication of Loperamide?

A
  • Acute ulcerative colitis
  • Antibiotic associated colitis
  • Abdominal distension
  • Conditions where inhibition of peristalsis
  • Acute bloody diarrhoea
63
Q

Caution of Loperamide?

A
  • Hepatic impairment

- History of drug abuse

64
Q

Interactions of Loperamide?

A

None

65
Q

Monitoring of Loperamide?

A
  • Stool frequency and abdominal monitoring
66
Q

Patient education for Loperamide?

A

The only purpose of loperamide is to help settle the diarrhoea.
It does nothing for the underlying cause.
Make sure patients know to stop taking it if they develop constipation, abdominal pain, or (in acute diarrhoea) they find they need to take it for more than 5 days.

Pharmacology (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions