Drugs used in Gastro-intestinal tract Flashcards
Aminosalicylates, anti-inflammatory drugs used in ulcerative colitis, eg sulfasalazine, mesalazine
REPORTING: Blood dyscrasias- sore throat, fever, rash, ulcers, bleeding
Mesalazine: switching brands- advise to report any changes in symptoms
Sulfasalazine: colours body fluids orange/yellow
Liquid paraffin- used as a lubricant for constipation
Not really recommended any more
Anal irritation, seepage of paraffin after prolonged use
Sucralfate- used for gastric ulcers and gastritis
BEZOAR formation- stone like mass found in GI system
Caution especially in critically ill patients in intensive care or with enteral feeds
Pancreatin- mixtures of enzymes used to aid digestion- CREON
Advise patients to maintain adequate hydration at high doses
Also advise that the capsules should be swallowed whole and not chewed due to an enteric coating.
Used in Cystic fibrosis
Magnesium containing antacids can have opposite side effects to those containing aluminium
Magnesium containing = laxative effects (diarrhoea)
Aluminium containing= constipation effects
Antimuscarinics e.g. atropine, hyoscine butylbromide (buscopan) used to reduce gastric motility
Caution- use in DOWNS SYNDROME
Antimuscarinc side effects: (same as anticholinergic): Constipation Dry mouth Urinary retention Dry skin Transient bradycardia
Proton pump inhibitors can cause electrolyte disturbance
Hyponatreamia (reduced sodium)
Side effects of the antidiarrhoeal drug loperamide
Flatulence!
Nausea
Headache
Side effects of bulk forming laxatives? Eg isoaghula husk (fybogel)
Flatulence
Abdominal distension (bloating)
These swell in contact with liquid and therefore advise to take with plenty of water and not to take immediately before bed
Stimulant laxatives side effects
Eg. Senna
Docusate sodium
Bisacodyl
Abdominal cramps
Diarrhoea if used in excess
Often abused to lose weight
Osmotic laxative e.g. lactulose, macrogols (movicol)
Increases water in the large bowel
Need patient to drink adequate amount of water for them to work
Can take 3 days to work
Nausea, vomitting, cramps, bloating, flatulence all side effects
What do the words “low Na+” on antacid preparations indicate?
Sodium content of less than 1mmol per tablet or 10ml dose. This is written on for people with hypertension
Should antacids be taken at the same time as other drugs?
No as this may impair absorption
They can also damage the enteric coating on tablets
When should PPIs be taken?
At least 30 mins before food for optimal absorption
What drug, used for GI ulcers, should be avoided in all trimesters of pregnancy and in women of a child bearing age unless absolutely necessary?
Misoprostol
Used for NSAID induced ulcers
Teratogenic
Safest PPI in pregnant women?
Omeprazole- only one not known to be harmful
H2 antagonists should be avoided
Diarrhoea advice in a pregnant woman?
Cannot give loperamide
ORT can be used
Safest laxative in pregnant women?
Bulk forming laxatives most appropriate- ispaghula husk I.e. Fybogel
Lactulose probably not harmful
Avoid stimulants and macrogols
Haemorrhoids in pregnant woman
Avoid steroid based preparations- e.g. Preparation H containing hydrocortisone
Local therapies may be used: germaloids cream or ointment or suppositories but NOT the spray
Which antiemetic drug can be purchased over the counter?
Cyclizine (antihistamine)
Metoclopramide and Domperidone no longer OTC: Metoclopromide risk in Parkinsons, Domperidone with QT prolongation effects so cardiac risks.
Can recommend Peptobismol to settle stomach but not very nice, and travel sickness tablets available.
What laxative and what anti-emetic are recommended for use in terminally ill patients?
Laxative- co-danthromer/ co-danthrusate (can colour urine red)
It is locally irritant- avoid contact with skin
Anti-emetic: Ondansetron, Haloperidol- these are good for opioid induce N&V.
(Haloperidol also used first line for delirium in palliative care- this is very common)
Which laxative should be used where there is faecal impaction?
impacted colon, your feces become dry and won’t budge, making it impossible to excrete them from your body
Should therefore use the OSMOTIC laxative to get water into the stool: MACROGOL (movicol) is used
What is the most common side effect of VERAPAMIL (rate limiting CCB)?
Constipation!
Does not appear to be an issue with any of the other CCB’s just Verapamil
Verapamil has a more profound effect on gut smooth muscle than the other calcium channel antagonists. It reduces gut motility and causes constipation.
When is metoclopromide contraindicated for treating sickness?
3 - 4 days after Gastrointestinal surgery
GI heamorrhage
GI obstruction
Under 18 years due to neurological effects
Which laxatives do we use in opioid induced constipation/ immobility (e.g. due to hospital stay)?
Regular LACTULOSE
PLUS SENNA PRN/ REGULAR!!
What is Colestipol? When should other medications be taken in relation to this drug?
A bile acid sequestrant used to lower cholesterol (LDL specifically)
Take other medication 1 hour before or 4 hours after this medication as it can effect absorption
Abdominal pain Vomiting Bloating Constipation Diarrhoa
Which one is not a typical symptom of IBS?
Vomiting
