OTC Flashcards
What is the CKS definition of constipation?
Passing stool less than 3 times a week
What is the referral criteria for constipation?
- Blood in stools
- black terry and mixed in stool: upper GI bleed?
- bright red blood: anal fissure/ haemorrhoids - Unexplained weight loss of appetite loss
- colorectal cancer? - Patients over 40 with a sudden change in bowel habit
- Medication ADR
- Constipation, lethargy, weight gain, hair-thinning, dry skin
- signs of hypothyroidism - Stimulant laxative abuse
- overuse = lazy bowel - Obstruction - abdominal distension, vomiting and colic pain
- Constipation >2 weeks
Which classes of medication can cause constipation?
Opioids
Iron
TCAs
Antimuscarinics
Diuretics
Aluminium antacids
Verapamil
Antihistamines
What is 1st line for constipation and what are their age limits?
Bulk-forming laxatives:
- ispaghula husk e.g. fybogel 6+
- sterculia e.g. normacol 6+
- methylcellulose
Works by increasing faecal mass
How long does it take for bulk-forming laxatives to work and what are the side effects of it?
2-3 days
SE: oesphageal or intestinal obstruction
abdominal distension and flatulence
What counselling is given with bulk-forming laxatives?
Swallow with water
Do not take immediately before bed
Maintain adequate fluid intake
What are the examples of osmotic laxatives and their age restrictions?
Ideal for hard stools - they increase water in colon
Macrogol e.g. laxido
Lactulose - 3+
Magnesium sulphate e.g. epsom salts - 12+
How long does it take for osmotic laxatives to work?
2-3 days
48 hours for lactulose
What are the side effects of osmotic laxatives?
Discomfort
Flatulence
Cramps
What type of constipation are stimulant laxatives suitable for?
Soft stool that is hard to pass
What is the maximum usage of stimulant laxatives?
1 week
What are examples of stimulant laxatives and their age restrictions?
Senna - 12+ (colours urine brown)
Bisacodyl e.g. dulcolax 10+
Sodium picosulfate - 10+
Docusate sodium 18+ (stool softener too)
Glycerin suppositories - 4g for adults, 2g for children under 12, 1g for infants
What is the onset of action for stimulant laxatives?
6-12 hours
Glycerin suppositories - 15-30 minutes
What are the side effects of stool softener laxatives?
e.g. liquid paraffin 3+ - no longer recommended due to harsh side effects
SE:
- anal seepage
- lipoid pneumonia
- malabsorption of fat-soluble vitamins ADEK
What are the side effects of stimulant laxatives?
Abdominal cramps
Excessive use: hypokalaemia, diarrhoea, lazy bowel
What counselling should be provided for stimulant laxatives?
- Take at night to go in the morning
- Senna colours urine yellow-brown
How do you treat constipation in pregnant women?
1st line: bulk-forming or lactulose
AVOID STIMULANT
How do you treat constipation in elderly?
Take caution recommending bulk-forming laxatives - risk of gut obstruction and difficult to increase fluid intake
How do you treat constipation in children?
1st line: lactulose
How do you treat opioid-induced constipation?
Lactulose + stimulant laxative
AVOID bulk-forming - can cause obstruction
What is the referral criteria for diarrhoea
- babies under 3 months
- children under 1, diabetic patients or elderly patients if they have had diarrhoea for >1 day
- children under 3 who have had diarrhoea for >3 days
- if the patient has signs of dehydration e.g. dry skin/reduced turgor, sunken eyes, dry tongue, drowsiness/light-headedness, less/ dark urine, sunken fontanelle
- blood or mucus in the stool
- gastric bleeding, bowel cancer, IBD? - long-standing change in bowel habit in those >50 and weight loss
- colorectal cancer? - suspected faecal impaction in elderly
- poorly formed stools still difficult to pass? - severe vomiting, high-grade fever
- recent travel abroad
- chronic diarrhoea >3 days
What medication can cause diarrhoea?
Magnesium antacids
NSAIDs
Iron (laxating or constipating)
Laxatives - overuse
Antibiotics
Digoxin
PPIs
Diuretics
SSRIs
How is diarrhoea treated?
1st line: ORT - all ages
- 1-2 sachets after each loose stool motion
2nd line: loperamide (12+)
- 2 capsules after each loose motion (max. 8 a day)
- not recommended in pregnancy or breast-feeding
Bismuth salicylate - 16+
- can also be used for dyspepsia and vomiting
- avoid in aspirin hypersensitivity
- causes black stools and tongue
How do you reconstitute ORT?
1 sachet in 200ml water (no fizzy drinks fruit juices)
- must use boiled and cooled water for babies <1 years
- must be reconstituted immediately before use but can be stored in the fridge for 24 hours
What lifestyle advice should be given for babies with diarrhoea?
Dilute formula to 1/4 of regular strength
- build back up to normal over 3 days
- diarrhoea causes temporary lactose intolerance
- feed more frequently than normal and supplement with ORT
What are the characteristics of GORD?
Burning sensation behind breast-bone and bitter acid taste
What are the symptoms of dyspepsia?
- Vague abdominal pain over the bellybutton
- bloating, belching and flatulence
- fullness
- N/V
- heartburn
What is the referral criteria for dyspepsia?
Anaemia (iron deficiency)
Loss of weight
Anorexia
Recently changes or new dyspepsia in >55
Malaena, haemostasis, persistent vomiting, dysphagia
- Peptic ulcers
- Cardiovascular problems
- pain radiating to the jaw, back and arms
- pain precipitated by exercise and not relieved by antacids - symptomatic treatment after 4 or more weeks
- previous gastric ulcer or GI surgery
- children
- regurgitation
7, jaundice or severe liver disease
How do you rule out peptic ulcer?
You must rule out peptic ulcer before treating:
- persistent gnawing, boring pain from one point of the abdomen indicates peptic ulcer
Gastric ulcer:
- pain aggravated by food, usually 30 minutes after a meal
Duodenal ulcer:
- pain when stomach empty
- pain 2-3 hours after eating
- awakening at night
When would you refuse a PPI or H2RA for dyspepsia?
Due endoscopy or C-urea test in 14 days because it can result in a false negative
What salt in antacids is constipating?
Aluminium
What salt in antacids is laxating?
Magnesium
What drugs do antacids impair the absorption of?
Do not take at the same time - leave 2 hour gap
- tetracyclines
- quinolones
- bisphosphonates
Avoid giving with enteric coated medication as can alter the pH of the stomach acid
What drugs and conditions should you avoid with antacids due to the high sodium content?
Hypertension
Heart, kidney or liver failure
Avoid in sodium-restricted diets e.g. lithium or CHD
Low sodium preparations = mucogel and maalox
What is the MOA, onset of action of and duration of action of H2RA?
MOA: acid suppressor
Onset of action: 1 hour
Duration of action: 9 hours
What is the age restrictions and maximum usage for H2RA?
E.g. ranitidine 16+
- maximum use 14 days
How do you take ranitidine?
1 x 75mg tablet when symptoms occur
- if symptoms persist for more than one hour or return = take another tablet
- maximum of 4 tablets in 24 hours