GI Pharmaceutical care

Question 1

Name two GI conditions for which a ‘borderline product’ can be prescribed and explain why the product works

Answer 1

• Crohn’s disease
• lactose intolerance
• coeliac disease
• dermatitis hepetiformis

Question 2

Explain the pathological basis of coeliac disease

Answer 2

The symptoms of coeliac disease
vary from person to person and can range from very mild to severe.
Symptoms of eating gluten, or being ‘glutened’, include
headaches, diarrhoea, stomach pains and lethargy. The symptoms may last from a few hours to a few days.
The reaction is not the same as an allergic reaction and does not cause anaphylactic shock.
Coeliac disease is known as a ‘multi system’ disorder – symptoms can affect any area of the body. Symptoms differ between individuals in terms of type and severity.
Weight loss with diarrhoea can occur, leading to severe illness resembling malnutrition.

Question 3

Discuss the major considerations when prescribing for a patient with a stoma

Answer 3

Considerations
Patient has to recover from surgery
Restore lifestyle to as normal as possible
Problems may relate to the stoma or to other conditions
Drug Tariff Part IXC - STOMA APPLIANCES (Colostomy, Ileostomy, Urostomy)
Prescribers and suppliers - note that products not included in the list are not prescribable
Stoma supplies come from mail-order dispensing services

Question 4

Symptoms when someone with caeliac disease eats gluten

Answer 4

headaches, diarrhoea, stomach pains and lethargy. The symptoms may last from a few hours to a few days

Question 5

Types of enteral nutrition

Answer 5

Sip Feeds/ Supplements

Nasogastric feeding

PEG/ PEJ Tubes

Distal Feeding

Question 6

Stroma need prompted by

Answer 6

The commonest causes are cancers of the bladder and colon, and inflammatory bowel disease.

Question 7

temporary vs permanent stroma

Answer 7

A temporary stoma is usually created to divert faeces away from surgically rejoined intestine or to provide an outlet for faeces if there is an obstruction.

A permanent stoma may be needed when a disease or its treatment results in loss of normal bowel or urinary function.

NB: Stroma patients may suffer from constipation

Question 8

List some drug related problems for patients with stromas

Answer 8

• enteric coating/SR formulations
• Laxatives
• Constipation in colostomy patients
• Antacids
• Iron preparations
• Compound analgesics
• Oral contraceptives
• Antibiotics
• Diuretics
• Digoxin
• Potassium supplements

Question 9

Why are enteric coated formulations unsuitable?

Answer 9

unsuitable

May not deliver full dose effectively if transit is rapid

Question 10

When and why are laxatives a problem?

Answer 10

should not be used in patients with an ileostomy where possible as they may cause rapid and severe loss of water and electrolytes.

Question 11

How should constipation in colostomy patients be dealt with?

Answer 11

should be treated by increasing fluid intake or dietary fibre. Bulk-forming
drugs can be tried. If they are insufficient, as small a dose as possible of a
stimulant laxative such as senna can be used with caution.

Question 12

Problems with antacids for stroma patients

Answer 12

The tendency to diarrhoea from magnesium salts or constipation from aluminium or calcium salts may be increased in patients with stoma.

Question 13

Problems with iron

Answer 13

may cause loose stools and sore skin in these patients. If iron is definitely indicated, an intramuscular iron preparation should be used. Modified-release preparations should be avoided

Question 14

Problems with iron preparations

Answer 14

may cause loose stools and sore skin in these patients. If iron is definitely indicated, an intramuscular iron preparation should be used. Modified-release preparations should be avoided

Question 15

compound analgesic problems

Answer 15

(contain codeine)- constipation

Question 16

problems with oral contraceptives

Answer 16

less reliable

Question 17

Problems with antibiotics

Answer 17

Can cause diarrhoea

Question 18

Diuretic issues/problems

Answer 18

cause dehydration and potassium depletion – use potassium sparing diuretic

Question 19

Digoxin problems

Answer 19

Patients with a stoma are particularly susceptible to hypokalaemia if taking digoxin, due to fluid and sodium depletion. Potassium supplements or a potassium-sparing diuretic may be advisable with monitoring for early signs of toxicity

Question 20

How to prescribe/administer potassium supplements to stoma patients

Answer 20

Liquid formulations are preferred to modified-release formulations. The daily dose should be split to avoid osmotic diarrhoea.

Question 21

Appliance issues

Answer 21

Leaking
Stoma size changes with time – refer to Stoma Nurse for measuring
Skin problems - Rash, non-adherence.
May need advice on cleansing agents, protective creams, sealants
On prescription - Skin Fillers and Protectives (Barrier creams, pastes, aerosols, lotions, gels, wipes)
Dexterity – ability to change bag
Odours – deodorants on prescription

Question 22

Antacid interactions

Answer 22

May impair the absorption of other drugs if taken at the same time (also in feeding tubes)
(e.g. ACE inhibitors, antiepileptics, antibacterials)

May cause dissolution of enteric coatings by raising the pH.
Makes pancreatic enzymes replacement less effective

May affect pH dependent renal excretion
(alkaline urine =↑excretion of aspirin and lithium)

Question 23

PPIs

Answer 23

Omeprazole, esomeprazole, pantoprazole
Enhance anticoagulant effects
INR increased - warfarin dose may need to be reduced

Enhance effects of phenytoin
Plasma concentration of clozapine reduced by omeprazole 	

Omeprazole can block enteral feeding tubes – switch to lansoprazole or esomeprazole

Question 24

Converting solid dosage forms to other formulations

Answer 24

Check relative (equivalent) bioavailability
Choose licensed product first
Liquid
Melts
orodispersible
Do not crush EC, modified release/slow release preparations
Crushing and opening capsules makes the product unlicensed

Effervescent tablets – some brands contain a significant quantity of sodium

Syrup – some brands contain sorbitol which can cause diarrhoea in large quantities

Oral hypoglycaemic agents – consider switching to insulin if patient cannot swallow