Management of Diarrhea Lecture Notes PDF PHARM 345 2025

Management of Diarrhea PHARM 345 Dr. Rene Breault Slides adapted from Dr. Tara Leslie and Dr. Nese Yuksel 1 Resources Chapter: Diarrhea in Minor Ailments and Chapter: Diarrhea in Therapeutic Choices, CPS Chapter 53 – Diarrhea, Co...

Management of Diarrhea PHARM 345 Dr. Rene Breault Slides adapted from Dr. Tara Leslie and Dr. Nese Yuksel 1 Resources Chapter: Diarrhea in Minor Ailments and Chapter: Diarrhea in Therapeutic Choices, CPS Chapter 53 – Diarrhea, Constipation and Irritable Bowel Syndrome, Dipiro's Pharmacotherapy 12eth edition Chapter Diarrhea. Mahmoud ed. Patient Assessment in Clinical Pharmacy 2 Objectives By the end of the lecture you should be able to: Describe the etiology, pathophysiology and causes of diarrhea. Discuss the therapeutic approach to treating diarrhea including pharmacologic and lifestyle measures. 3 Definition of diarrhea Frequent passage of loose, watery stool (>3 per day) Normal stools – 100 – 300 gm/daily ○ >300 gm – diarrhea Classification of diarrhea Acute - 14 days Chronic - >30 days duration or repeated episodes 4 If you pass any stools, can you describe its consistency and colour? 5 Complications of diarrhea Fluid and electrolyte disturbances Dehydration ○Infants, young children, elderly ○Patients with chronic diseases such as renal failure and cardiovascular disease May also see: fever, abdominal pain, flatulence, weight loss/anorexia if severe. Depending on cause: blood, mucus, pus may be present in stools. Hemorrhoids 6 Types of Diarrhea Osmotic poorly absorbed substances draw water into the bowel lumen Secretory Derangement of fluid and electrolyte transport across the enterocolonic mucosa stimulating substance increases secretion or decreases absorption of water/electrolytes Exudative/inflammatory Inflammation Increased gut motility reduced contact time in small intestine premature emptying of the colon bacterial overgrowth 7 Common causes of acute diarrhea Infectious - one of the most common reasons for acute diarrhea ○ Bacterial – ie E. coli, Salmonella, Shigella, C. difficile etc ○ Viral – ie rotavirus, norovirus, etc ○ Food toxins ○ In developing countries could lead to chronic diarrhea 8 Drugs Commonly Associated with Diarrhea ⚫ Drug Laxatives ⚫ Antacids (magnesium) ⚫ Antibiotics ⚫ Cholinergic drugs ⚫ Promotility agents ⚫ Prostaglandins (e.g. misoprostil) ⚫ SSRI Antidepressants ⚫ Sulfasalazine ⚫ Antihypertensives (propranolol, ACE-I) ⚫ NSAIDs ⚫ Some chemotherapeutic agents 9  Medical Conditions Associated with Diarrhea Type of Diarrhea Description Examples Osmotic Poorly absorbed poorly or non-absorbed carbohydrates (sorbitol, mannitol) substances draw water lactose intolerance into bowel lumen malabsorption syndromes celiac disease medications (magnesium containing antacids) Secretory Derangement of fluid bacterial infections (toxins) and electrolyte excessive bile salts transport across the hormone producing tumours enterocolonic mucosa medications (some chemotherapy) Exudative/inflammatory inflammation inflammatory bowel disease (IBD) other types of colitis infections Increased gut motility increased gut motility irritable bowel syndrome (IBS) (dysmotility) hyperthyroidism medications (metoclopramide) 10 Clostridium difficile infections (CDI) Anaerobic bacteria – Clostridium difficile Associated with antibiotics: ○ Most common: fluoroquinolones, cephalosporins, clindamycin, carbapenems ○ Least common: aminoglycosides, TMP/SMX, tetracyclines, metronidazole Range of symptoms includes severe symptoms with watery diarrhea, abdominal pain/distension, fever etc to no symptoms (carrier state) 11 Traveller's Diarrhea Travel to developing countries with poor standards for hygiene/sanitation Onset usually 1 – 2 days of ingesting contaminated food – and up to 7 – 10 days after returning home. May be accompanied by abdominal cramping, fever or vomiting. Causes: bacteria (enterotoxigenic Escherichia coli, Campylobacter, Shigella or Salmonella), parasites (ie Giardia) and viruses (Norovirus, Rotavirus) Most cases are self-limiting (< 7 days) 12 Patient assessment: Diarrhea See Figure 2 of Chapter: Diarrhea, Minor Ailments, CPS 13 Approach to Diarrhea Three step approach: 1. Recognize consequences of the diarrhea (dehydration, electrolyte abnormalities) and correct or refer as appropriate. 2. Identify underlying cause for diarrhea Refer if “red flags” 3. Treat/manage underlying cause. 4. Self care (non-pharm, OTC), Prescription antidiarrheals 14 Patient Assessment Assess signs and symptoms SCHOLAR Gather additional patient information Medical history (acute and chronic) Medication history (new and ongoing), prescription, non-prescription, herbal Social history (including recent experiences) Allergies or intolerances (food & drug) Rule out Red Flags ○ refer if complications present (signs/symptoms of significant dehydration) ○ refer if etiology (cause) requires medical attention 15  SCHOLAR - Symptom Assessment Mnemonic SCHOLAR Questions What specific questions would you ask for diarrhea? Symptoms What are the main Other symptoms (fever, cramping, pain, N/V, signs of symptoms? dehydration) Are you passing gas? Characteristics What are the symptoms like? Stool frequency Stool consistency (soft vs fluffy vs liquid) Presence of blood, mucus, pus History What has happened in the Travel history, past? Ingestion of foods (food borne illness, food sensitivities) What has been done so far? Medications (eg: antibiotics, laxative use) Medical conditions (IBD, cancer, celiac, etc) Onset When did it start? When did the diarrhea start? How did it start? consider sudden onset vs ongoing vs periodic (acute/chronic) Location Where is the problem? n/a (unless other symptoms such as pain) Aggravating Factors What made it worse? Consider questions in history Remitting Factors What makes in better? Has anything been tried so far? For how long? What dose? How did it work? Any side effects? 16 Patient Assessment: Diarrhea Assess for “red flags” that should be referred. Features of Diarrhea: Fever (>38.5℃) Features of the Patient: Blood or abnormal mucus in stools Young children (6 loose stools Pregnancy per day for greater than 48 hours) Presence of multiple chronic conditions Diarrhea > 7 days (ie cardiovascular, CKD, DM) Signs of debilitating dehydration Immunocompromised (HIV, cancer) Clostridium difficile infections Chapter: Diarrhea, Minor Ailments Overflow diarrhea due to fecal (CPS) Chapter Diarrhea. Mahmoud ed. impaction (bowel obstruction) Patient Assessment in Clinical Pharmacy 17 Therapeutic Approach: Non-pharmacologic Discontinue medications/foods that could be causing diarrhea Adequate rehydration ○ Maintain electrolyte balance ○ Clear fluids for 24 hours ○ Oral rehydration therapy ○ Avoid fruit juice and carbonated drinks 18 Oral Rehydration Therapy Oral rehydration solutions (ORS) contain appropriate proportions of Na+, K+, glucose/dextrose and other electrolytes. Available products: ○ Gastrolyte, Pedialyte, WHO-ORS, Hydralyte Home ORS can also be made – however commercial products preferred Dose: 19 https://medicalguidelines.msf.org/viewport/EssDr/english/oral-rehydration-salts-ors-16684387.html ORS works because of the Sodium-Glucose Cotransport System http://www.h2ors.com/ors-science/ 20 Oral Rehydration Solutions Name mOsm/L CHO g/L WHO-ORS 245 20 Pedialyte Soln 250 25 Gastrolyte Pkts 240 18 Cola/Ginger Ale 550 50-150 Apple Juice 700 100-150 Chicken Broth 450 0 Tea 5 0 Gatorade 330 45+ mOsm/L – osmolality, CHO - 21 carbohydrates ORS Products Examples 22 Treatment approaches: Non-pharmacologic Diet: Stop ingestion of poorly absorbed carbohydrates (ie sorbitol, mannitol, etc) Complex carbohydrate diet – BRAT diet usually not recommended now. Regular diet in 1 – 3 days 23 Therapeutic Approach: Pharmacologic Options 24 Opiates and their derivatives Peripheral action: Loperamide (Imodium®) – OTC ○ Binds to opiate receptor in the gut wall ○ Inhibits release of acetylcholine + prostaglandins ○ Reduced peristalsis, increases intestinal transit time ○ Increased tone of anal sphincter - reducing incontinence and urgency Central + peripheral action: Diphenoxylate + atropine (Lomotil®) - Rx ○ Slows digestion/gut motility ○ Atropine added to prevent misuse 25 Loperamide Adult Dose: 4mg, then 2mg after each bowel movement (max 16mg/day) Duration: recommended not to be used for more than 2 days (however, can be used longer in some patients with chronic diarrhea) Role: moderate to severe diarrhea Children: ○ Avoid in children