1. Drugs for Bowel Disorders and other GI Conditions
Chapters 40 & 41

2. Nausea Definitions of nausea on the Web:
the state that precedes vomiting
disgust so strong it makes you feel sick wordnetweb.princeton.edu/perl/webwn
comes from the Greek word for ship, naus, which currently can be defined as a queasy or upset stomach.

3. Emesis (Vomit)
Emesis : the reflex act of ejecting the contents of the stomach through the mouth wordnetweb.princeton.ed
From the Indo-European root wem- (to vomit), the source of the words such as emetic and wamble (to feel nauseated).
The body’s protective mechanism to eject harmful/toxic materials or substances
Adams, P., Holland, L., Urban, C., 2011

4. Pathophysiology
Vomit Center located in Medulla of Brain. Receives sensory input from G.I., inner ear & Chemoreceptor Trigger Zone (CTZ) in cerebral cortex. Noxious stimuli (dizziness, spoiled food/infection, drugs/anesthesia, pain or trauma, pregnancy) signals the Vomit Center which in turn stimulates the stomach resulting in nausea &/or vomiting.

5. Antiemetics 1st Group: Serotonin (5-HT3) Receptor Antagonist
Odansetron (Zofran) 4 mg PO/IV Q 4-8 hrs PRN n/v
Action: Blocks Serotonin Receptors in CTZ and Vagal Nerve terminals in G.I. Tract.
Indications: Post General Anesthesia & Chemotherapy
Adverse Effects
H/A, drowsiness, fatigue, constipation, diarrhea
Serious: dysrhythmias, extrapyramidal symptoms (EPS)
Pearson Education, Inc. 2008, 2011.
Wilson B., Shannon, M., Shields, K., 2009

6. Anti-Emetics
2nd Group: Phenothiazines (primary use as an antipsychotic)
Action: affects CTZ to inhibit n/v. Larger doses
inhibit signals to Vomit Center by blocking dopamine receptors.
Prochlorperazine (Compazine) (prototype drug)
5-10 mg PO TID or QID: mg IV (no more than 5 mg/min), serious adverse effect includes extrapyramidal symptoms (EPS): akathisia or restlessness, dystonia, parkinsonism.
Metoclopramide (Reglan) (action unknown)
10mg PO/IV Q6-8h, aids gastric emptying

7. Phenothiazines Continued
Promethazine (Phenergan)
mg PO, PR or IM Q 4-8h PRN
(prevents histamine-mediated response)
Adverse Effects
Common: dry mouth & eyes, blurry vision, constipation, drowsiness, photosensitivity
Serious: neuroleptic malignant syndrome, EPS, agranulocytosis
Pearson Education, Inc. 2008
Nursing Drug Handbook 2008
Davis Drug Guide 2011

8. Antiemetics Scopalamine (Hyoscine, Transderm-Scop)
3rd Group: Anticholinergics/ Antihistimines
Scopalamine (Hyoscine, Transderm-Scop)
Transdermal 0.5 mg q 72hrs (usually placed behind the ear)
Action: Blocks acetylcholine on postganglionic cholinergic nerves resulting in CNS depression, marked sedation and tranquilizing effects, controls oropharyngeal secretions
Adverse Effects:
Common: drowsiness, dry mouth, blurred vision,
Serious: hypersensitivity reaction, sedation, tremors, seizures, hallucinations, paradoxical excitation (mostly in children), hypotension
Pearson Education, Inc. 2008
Wilson B., Shannon, M., Shields, K., 2009

9. Diarrhea
frequent and watery bowel movements; can be a symptom of infection, food poisoning, colitis or a gastrointestinal tumor wordnetweb.princeton.edu/perl/webwn
Diarrhea (from the Greek, διὰρροια meaning "a flowing through"), also spelled diarrhoea, is the condition of having three or more loose or liquid bowel movements per day. It is a common cause of death in developing countries and the second most common cause of infant deaths worldwide. ... en.wikipedia.org/wiki/Diarrhea

10. Diarrhea
Primary Goal: assess and treat the underlying cause of the diarrhea. Recent travel? Immunocompromised? Antibiotic treatment? Dietary Habits? Over the Counter (OTC) Medications? Toxins?/Infections?/Disease?

11. Anti-Diarrheal: Opioids
Diphenoxylate 2.5mg & Atropine 0.025mg (Lomotil), is a prototype drug. 1-2 tabs or 5-10 ml tid-qid
Action: slows peristalsis, allowing water to be reabsorbed from the colon, promoting a more solid stool. Atropine is added to discourage abuse (causes drowsiness, dry mouth, tachycardia).
Adverse Effects: no analgesic effect, dry mouth, nausea, constipation, occasional dizziness or drowsiness. Serious:Paralytic ileus with toxic megacolon, respiratory & CNS depression.
Pharmacology for Nurses, Adams, Holland & Bostwick Pearson/Prentice Hall 2nd Ed. 2008
Davis Drug Guide 2011

12. Anti-Diarrheal: Opioids
loperamide (Imodium): 4 mg PO initially, then 2 mg after each diarrhea episode
Action: inhibits peristalsis, reduces fecal volume and loss of fluid and electrolytes
Adverse Effects: dry mouth, abd pain, n/v, constipation, dizziness or drowsiness.
Davis Drug Guide 2011

13. Anti-Diarrheal-Miscellaneous
Bismuth subsalicylate (Pepto-Bismol)
Action: antisecretory, anti-inflammatory, binds and/or absorbs bacterial and viral enteropathogens.
Dosage: Mild nonspecific diarrhea: 30ml or 2 tabs PO
q 30 min-1 hr. Max 8 doses for no longer than 2 days.
Adverse effects: temporary darkening of tongue & stools, salicylism with high doses
Nursing 2008 Drug Book
Pearson Education, Inc. 2008

14. Anti-Diarrheals Contraindications:
Should not be used when patient has a suspicion of or is diagnosed with pseudo-membranous colitis (Toxic Megacolon) or severe ulcerative colitis. Anti-Diarrheals may worsen or mask these conditions. Toxic Megacolon has occurred with patients who have ulcerative colitis who have taken loperamide (Imodium), an opioid anti-diarrheal.

15. Constipation Constipation: a common GI complaint
4+ million Americans/yr
2.5 million Dr.’s office visits a year, most often
being female adults 65 yrs & older, also a common problem following childbirth or surgery.
Self-treatment of constipation with over-the-counter (OTC) laxatives is the most common aid. Around $725 million/yr spent on laxative products in U.S. digestive.niddk.nih.gov/ddiseases/pubs/constipation/ - Cached - Similar

16. Laxatives: Bulk Forming
Psyllium Mucilloid (Metamucil, etc.) 1-2 tsp in 8 oz water followed by 2nd glass daily prn
Action and Use: This Prototype Drug is derived from the seed of the plantain plant. It is an insoluble, indigestible fiber, when taken with enough water, swells to increase the size of the fecal mass, stimulating the defecation reflex.
Adverse Effects: rare, produces less cramps than stimulants. If insufficient water is taken, can cause esophageal or intestinal obstruction.
Pharmacology for Nurses, Adams, Holland & Bostwick Pearson/Prentice Hall 2nd Ed. 2008

17. Laxatives: Stimulant Bisacodyl (Dulcolax) 10-15 mg PO daily
Action: Unknown. Increases peristalsis probably by direct effect on smooth muscle, either by irritation or stimulation of the colonic intramural plexis. Also promotes fluid accumulation in colon and small bowl.
Adverse Effects: GI-cramps, n/v/d with high dose, rectal burning with suppository, dependence and/or protein-losing enteropathy with long term or excessive use
Nursing 2008 Drug Book

18. Laxatives: Saline and Osmotic
Magnesium hydroxide (Milk of Magnesia -MOM) ml daily PRN
Polyethylene glycol (Miralax) sodium 17gm daily in 8 oz liquid x 2-4 days
Sodium biphosphate (Fleet Phospho-Soda)
15-30 cc mixed in H2O daily PRN
Adverse Effects:
Common: Diarrhea, abd. Cramping
Serious: Hypermagnesemia with MOM (dysrhythmias, respiratory failure)

19. Laxatives: Stool Softener/Surfactant
docusate (Surfak, Colace, Dialose, etc.)
50-500mg PO daily
Adverse Effects:
Abd. Cramping, diarrhea
No serious adverse effects
Pearson Education, Inc. 2008

20. Laxatives: Miscellaneous
Mineral Oil ml PO BID
Adverse Effects:
Diarrhea, nausea
Serious: nutritional deficiencies, aspiration pneumonia
Pearson Education, Inc. 2008

21. Laxatives: Herbal Agent
Senna, large genus of flowering plants in the family Fabaceae en.wikipedia.org/wiki/Senna_(genus) - Cached – Similar
Action: irritates the wall of the bowl and increases peristalsis
Adverse Effects: abdominal cramping and diarrhea, no serious effects.

22. Laxatives Contraindications: Absence of Peristalsis
Sudden, unexplained change in bowl pattern
esophageal obstruction
intestinal obstruction
fecal impaction
undiagnosed abdominal pain

23. Case Study
Mrs. P. is an 86 y.o. female admitted to the Medical Unit with the diagnosis of Dehydration and Diarrhea. She has a history of constipation for which she takes OTC laxatives. Admitting VSS: Temp BP 102/55, HR 104 & thready, RR 18, O2Sat 94 on RA. Weight 40 kg. Ht. 5’ 1”. She complains of feeling weak, tired and has mild abdominal cramping. She states she thinks she had 3 loose BM’s today and can not remember how many yesterday. Prior admit to the hospital 3 weeks ago for a Urinary Tract Infection (UTI).

24. Neuman Model
What level of Mrs. P.’s Lines of Defense/Resistance are penetrated?
What Psychological Variable(s) do you think might be involved?

25. Admission Orders IV D 5 1/2 NS at 75 cc/hr Soft low fiber Diet
Up with assistance
Labs: CBC and Lytes in the am
Urinalysis, Culture and Sensitivity if indicated
Stool for Clostridium difficile
I & O
Tylenol 325 mg PO, 1 for mild pain, 2 for moderate pain

26. Clostridium difficile
C. difficile toxin, also known as pseudo-membranous colitis, is a spore-forming gram+ anaerobic bacteria producing toxins A & B, damaging the large intestine, causing diarrhea. Commonly seen in clients following chemotherapy, antibiotic treatment, invasive procedures, or who use stool softeners or laxatives. Most cases reported in clients older than 65. Most common cause of nosocomial infection for hospitalized clients.
Black J., & Hawks J., Medical-Surgical Nursing 8th Ed. 2009
CDC 2010

27. Nursing Process
What Potential/Actual Nursing Diagnosis would apply to Mrs. P?
What Goal or Outcome would you expect?

28. Nursing Process Focus: Clients Receiving Antidiarrheal Therapy
Potential Nursing Diagnosis
Fluid Volume, Imbalanced, Risk for : Less than Body Requirements, related to loss secondary to diarrhea
Injury (falls), Risk for, related to weakness, drowsiness secondary to drug therapy/electrolyte depletion
Infection, Risk for, related to bacterial, viral, or other infestation in the bowel
Deficient Knowledge (drug therapy)

29. Planning: Client Goals and Expected Outcomes
The client will:
Report relief of diarrhea
VSS and Laboratory values WNL
Demonstrate an understanding of the drug’s action by accurately describing side effects and precautions.
Report persistent diarrhea, constipation, abd. pain, blood in stool, confusion, dizziness, altered body temperature.

30. Implementation (Interventions/Rationales & Client Education/ Discharge Planning
Minimize risk of dehydration and electrolyte imbalance (secondary to diarrhea)
Encourage PO fluids
Instruct client about foods/fluids rich in electrolytes
Monitor frequency, character and amount of stool, Perform routine and PRN abdominal assessments
Client to report abd. cramping, fevers, increased fatigue and or lethergy

31. Implementation Monitor for dry mouth (side effect of medicine)
Hard candy, ice chips, chewing gum
Prevent over dosage of medication (can cause constipation).
Instruct client/significant other use of dropper/medicine cup, etc.

32. Implementation Fall Prevention
Instruct client to get up with assistance only
call bell in reach, client to use when need to get out of bed
Avoid driving/hazardous activities until effects of drugs are known
Avoid ETOH and other CNS depressants

33. Implementation
Monitor Electrolyte Levels (Imbalances may occur with diarrhea)
Monitor lab results
Client keep all laboratory appointments
Report any unusual muscle cramping or weakness

34. Evaluation of Outcome Criteria
Confirm that client goals and outcomes have been met
Client reports relief of diarrhea
Client demonstrates understanding of drug’s action by accurately describing proper use, side effects and precautions
Client verbalizes signs and symptoms to report to health care provider
Pearson Education, Inc. 2008

35. Mrs. P.
On the second hospital day, Mrs. P. reports she has no abdominal cramping and that her last loose BM was yesterday evening (which you confirmed in your chart review). Her VSS are WNL, she is taking adequate PO fluids, has no N/V, and is making adequate urine. Her IV has been slowed to 50 cc’s/hr. Both stool for C. difficile & urinalysis to rule out infection resulted negative. New orders: Lomitil 5 mg PO PRN loose stool, max 20 mg/daily.

36. Appetite Suppressants/Anorexiants
Drugs used to induce weight loss by suppressing appetite and hunger
Obesity defined as 20% above ideal body weight determined by BMI (kg Wt/meters Ht)
In the U.S. >$33 Billion/yr spent on weight-reduction products & services; >1 Million adults using these products are not overweight.
Pearson Education, Inc. 2008, 2011.

37. Appetite Reduction
1970’s-amphetamines/dextramphetamines (Dexadrine): highly addictive—Rarely prescribed now
1990’s-fenfluramine & phentermine
(fen-phen): heart valve defects from fenfluramine—removed from market

38. Appetite Suppressants
2000: phenylpropanolamine (OTC) removed from market due to increased incidence of CVA’s and cardiac events
2004: ephedra alkaloids, OTC weight loss products, removed from market – increased adverse cardiac events
Pearson Education, Inc. 2008, 2011.

39. Weight Loss
orlistat (Xenical) blocks lipid absorption in the GI Tract by binding to gastric and pancreatic lipases and inactivating them. Also blocks fat-soluble Vitamins and Coumadin. Small result in weight reduction compared to placebo.
Side Effects If medicine taken with diet high in fat content: flatus with discharge, oily stool, abd. pain
Available by Prescription & OTC
Pearson Education, Inc. 2008, 2011.
AHFS® Consumer Medication Information. © Copyright, The American Society of Health-System Pharmacists, Inc.,

40. Rx for Weight Loss Sibutramine (Meridia)
Action: Selective Serotonin Reuptake Inhibitor (SSRI) appetite suppressant for short term control (1 year) when combined with reduced calorie diet and exercise; results in 5-10% weight loss. Obesity (BMI >29 or BMI >26 for pt. with hx of HTN, DM, ↑Lipids).

41. Sibutramine (Meridia)
Initial Dose: 10 mg daily
Adverse Effects: H/A, insomnia, dry mouth. May have weight gain after drug discontinued.
Contraindications: Eating disorders, taking Monoamine Oxidase (MAO) Inhibitors.
Caution: patients with cardiac history, can cause tachycardia and elevate BP.
(other SSRI’s: Prozac and Zoloft)
Pearson Education, Inc. 2008, 2011.
Nursing 2008 Drug Book
Davis Drug Guide 2011

42. Pancreatic Enzymes
Pancrelipase (Pancrease) contains lipase, protease and amylase, of pork origin, to break down lipids, starches and proteins in the gut. Used as replacement therapy for clients with deficient pancreatic exocrine secretions (due to pancreatitis, cystic fibrosis).
Dose: 1-3 capsules before/with meals
Adverse Effects: uncommon but can cause N/V/D, hyperuricosuria.
Contraindications: allergy to the drug or pork products
Pearson Education, Inc. 2008
Davis Drug Guide 2011

43. Mrs. P.
Mrs. P. asks the Nurse to bring her two Dulcolax tablets. “Oh, I take them every day. It is the only way I stay comfortable!” The nurse asks Mrs. P. how long she has been taking Dulcolax and when was her last dose. As they are speaking, Mrs. P.’s son, John, walks into her room. “I’ve taken my Dulcolax for years, they help keep me regular. I think I took my last dose yesterday morning like always.” It becomes evident Mrs. P. had continued to take the Dulcolax after her episodes of diarrhea had occurred, exacerbating her condition.

44. Mrs. P. had not been thinking clearly, was forgetful and or did not understand the drug action. John had not been aware of his mothers habits. The nurse instructs and educates the patient and her son that a diet high in fiber (fresh fruits and vegetables, bran), adequate water, and moderate activity, or exercise, as tolerated, can minimize dependence upon laxatives. The nurse instructed them that the use of a laxative should not be taken when diarrhea occurs and that bowel stimulants are for a period of 1 week use only, not every day.

45. Mrs. P.
In addition, the nurse explains chronic use of the various bowel stimulants can effect the body’s salt balance, causing increased phosphate and Na+, and/ or decreased Ca++, Mg++, and K+. These conditions can cause confusion and disorientation, as well as heart and muscular dysfunction. Mrs. P. and her son John were grateful for the information. John stated he will now be more involved with his mother’s care and monitor her more closely now that he better understands her health habits and behaviors.

46. Antiulcer Drugs Indications: Peptic & Duodenal Ulcer Disease, & Gastroesophageal Reflux Disease (GERD)

47. Proton Pump Inhibitors
Reduces gastric acid secretion by binding to H+, K+ ATPase and prevents acid from being secreted.
Omeprazole (Prilosec). PO 20-60mg 1-2X daily for 4-8 weeks. Onset of action up to 2 hours after taking, duration up to 72 hours.
Pantoprazole (Protonix): 40mg PO/IV daily
Adverse Effects: H/A, n/d, rash, dizziness; rare serious effects.
Adams, P., Holland, L., Urban, C., 2011

48. H2-Receptor Antagonists
Activation of Histamine2 (H2) results in the secretion of stomach acid. H2-Receptor Antagonists suppress the release of acid by the parietal cells thereby raising the pH of the secretions in the stomach.
famotidine (Pepcid): 20 mg PO/IV BID or
40 mg PO QHS
Adverse Effects: H/A, nausea, dry mouth.
Rare: musculoskeletal pain, tachycardia, blood dyscrasias, blurred vision.
Adams, P., Holland, L., Urban, C., 2011

50. References
Adams, P., Holland, L., Urban, C., Pharmacology for Nurses, A Pathophysiological Approach, 2nd Ed., 2008, 3rd Ed., 2011, Pearson Education, Inc.
Nursing Drug Handbook 2008, Lippincott, Williams & Wilkins
Wilson B., Shannon, M., Shields, K., Nursing Drug Guide 2009, Prentice Hall
Basic And Clinical Pharmacology 10th Ed. Katzung, B., 2007
AHFS® Consumer Medication Information. © Copyright, The American Society of Health-System Pharmacists, Inc.,
Davis’s Drug Guide for Nurses 2011, Deglin, J., Vallerand, A., Sanoski, C., F.A. Davis Co., Philadelphia