Constipation

Lubricating Agent (MOA, Onset, Dose, Side Effects, Precautions,Advantage/Disadvantage, Recommended for, Counseling Point)

(mineral oil) MOA: decreases water absorption into colon, coats stool Onset: liquid is 6-8 hours, enema is 5-15 min Dose: 5-45 mL PO daily or 118 mL PR single dose Side Effects: Lipid Pneumonia (risk factors are pregnancy, children under 6, old, bed bound, difficulty swallowing) anal leakage/irritation, abdominal cramping, nausea, diarrhea, vomiting Precautions: Do not take with emollient and can cause aspiration Advantage: minimally absorbed Disadvantage: NO for pregnant women (decreases absorption of fat soluble vitamins), hypersensitivity in longterm use Recommended for: no one really :( Counseling Point: Take when sitting upright, do not take before bed, do not take with emollients, discuss decreased absorption of vitamins, take 2 hours before or after meals, decrease dose if anal leakage

6 Groups of Pharmacologic Treatment for Constipation

1. Bulk Forming Agents 2. Emollients 3. Lubricating Agents 4. Saline laxatives 5. Hyperosmitc Agents 6. Stimulant Laxatives

Nonpharmacologic treatments

1. increase fiber intake to 25-30 g: eat more veggies, fruits, oats, nuts, prunes!! 2. increase exercise 3. increase water intake 4. train bowel habits: 30 min after meals or soon after waking and do not ignore urge to go poo

4 Causes of Constipation

1. lifestyle: dehydration, lack of exercise, poor bowel habits, holding in poo, lack of fiber 2. medications: decreases GI motility: anticholinergics and opioid analgesics; Causes shrinking of tissues: divalent ions like Ca, Mg, Al, and iron; decreases GI contractility: Ca channel blocker 3. diseases: uncontrolled hypothyroidism and diabetes, stroke, psychological like depression and eating disorder 4. structural: issues with pelvic floor or external sphincter

Emollient (MOA, Onset, Dose, Side Effects, Precautions, Advantage/Disadvantage, Recommended for, Counseling Point)

AKA Docusate Sodium or Colace MOA: decreases surface tension of oil/water interface to form mush, aka stool softener Onset: 24-72 hours, up to 5 days Dose: 500 mg/day split to 1-4 doses or typically 100-200 mg once to twice/day Side Effects: abdominal cramping and diarrhea Precautions: if taken increased dose, sweating, cramps, arrhythmias, and weakness may occur Advantage: not absorbed and best prevention for constipation Disadvantage: may increase absorption of mineral oil!! and bitter Recommended for: patients who should not strain such as those who are post surgery, postpartum, hemorrhoids, terrible HTN, and arrhythmias; ALSO for opiate-induced constipation (often given with stimulant laxatives) Counseling Point: take with milk/water/food, hold for loose stools

Hyperosmotic Agent (MOA, Onset, Dose, Side Effects, Precautions, Advantage/Disadvantage, Recommended for, Counseling Point)

AKA PEG-3350 (Miralax), Glycerin (Fleet suppository) MOA: creates gradient to increase water absorption into colon, causing distention and evacuation Onset: PO: 24-72 hours; PR: 15-30 min Dose: PO: 17 g/day; PR: 3 g/day Side Effects: Rectal irritation, abdominal cramping/discomfort, diarrhea Precautions: Rectal irritation if used >2 times/day, chronic use might cause decreased [K+] Advantage: no known DDI, minimally absorbed, useful for idiopathic constipation Disadvantage: abdominal discomfort Recommended for: Idiopathic causes, bowel evacuation for lower GI procedures Counseling Point: Take with 4-8 oz of fluid, if have renal disease discuss with physician

Prevalence of Constipation

Age >65 years, children/infants, pregnant women, women>men, increased risk for patients who are low income and nonwhite

Stimulant Laxatives- Anthraquinone (MOA, Onset, Dose, Side Effects, Advantage, Precaution, Patient Counseling)

Anthraquinone: Senna MOA: metabolized by bacteria in gut to active form that simulates colonic motility: pushes (often prescribed with Colace for opioid induced constipation) Onset: 6-12 hours (up to 24) Dose: 8.6 to 17.2 mg PO daily Side Effects: Abdominal Cramping, urine discoloration, melanosis coli (reversible benign discoloration of colon) Advantage: minimal absorption; used as second line for simple constipation and bowel prep Precaution: electrolyte and fluid deficiencies, mal-absorption resulting from excess hypermotility, hypokalemia; do not use in patients with rectal bleeding, intestinal obstruction, appendicitis Patient Counseling: Bisacodyl warning: do NOT take w/in 1 hour of antacids, H2RAs, PPI, or milk and do NOT crush/chew

Names/Dose of Stimulant Laxatives

Anthraquinone: Senna (PO 8.6 to 17.2 mg PO daily) Diphenylmethane: Bisacodyl (5-30 mg PO daily) Castor Oil (15-60 mL PO daily)

Treatment of constipation in pregnant women

Cause: Uterus compresses colon Encourage to increase in fiber and fluid and physical activity Safe: Bulk forming agent, Docusate Sodium, maybe Senna (caution in near term or unstable pregnancy) NOT safe: mineral oil (interferes with vitamin absorption), Castor Oil (may induce laber) , saline laxative (systemic absorption)

Constipation in Children

Cause: emotional distress, dehydration, diet changes, medical conditions Increase water and fiber Treatment: Barley Malt extract (safe for infants); glycerin suppositories (<5 yrs ok), Miralax, milk of magnesia, magnesium citrate (>1 year old) Avoid: Mineral Oil, Stimulant Laxative, Sodium Phosphate Enemas

Constipation in Elderly

Cause: lifestyle, diet, medical conditions; chronic laxative use is common Concern: loss of fluid caused by aggressive laxative treatment. Shouldn't use stimulant laxative chronically except when on chronic opioids (prevention) Bulk-forming agents, Docusate sodium Treatment: glycerin suppositories, Miralax (safe for patients with cardiac/renal disease), Senna Avoid mineral oil

Stimulant Laxatives: Diphenylmethane (MOA, Onset, Dose, Side Effects, Advantage, Precaution, Patient Counseling)

Diphenylmethane: Bisacodyl MOA: stimulates bowel motility by local irritation of mucosa and increases secretion of fluids in bowel Onset: PO: 6-10 hours; PR: 15-60 min Dose: 5-30 mg/day Side Effects: Abdominal cramping (worse than Senna); burning sensation in rectum for PR Advantage: minimal absorption; used as second line for simple constipation and bowel prep Precaution: electrolyte and fluid deficiencies, mal-absorption resulting from excess hypermotility, hypokalemia; do not use in patients with rectal bleeding, intestinal obstruction, appendicitis Patient Counseling: Bisacodyl warning: do NOT take w/in 1 hour of antacids, H2RAs, PPI, or milk and do NOT crush/chew

Names/Dose of Emollients

Docusate Sodium (Colace) PO: 500 mg/day (divided to 1-4 doses) or 100-200 mg/day (once to twice/day)

Bulk Forming Agents (MOA, Onset, Dose, Side Effects, Precautions, Advantage/Disadvantage, Recommended for, Counseling Point)

MOA: increases water absorption to increase bulk, stimulating peristalsis Onset: 12 to 24 hours, max is 72 hours Dose: 2-3 g Side Effects: flatulence and bloating Precautions: inhalation, esophageal obstruction: risk is for those who have difficulty swallowing, have limited water intake (heart failure or kidney problems), or are bed bound taking opioids Advantage: not absorbed, natural, safe long term, and replaces fiber Disadvantage: space out 1-2 hours from other meds because ions can chelate with tetracycline antibiotics and fluoroquinolones Recommended for: pregnant women, those who are lacking fiber, first line for constipation Counseling point: take with 8 oz of water, space it out 1-2 hours from other meds, stay hydrated!

Saline Laxatives (MOA, Onset, Dose, Side Effects, Precautions, Advantage/Disadvantage, Recommended for, Counseling Point)

MOA: ions draw water into colon, which increases pressure and intestinal mobility Magnesium stimulates bowel motility and fluid secretion Onset: Oral is 30 min-3 hour; rectal is 2-5 min Dose: Oral: 15-45mL/day once before bedtime; rectal is 4.5 oz enema Side Effects: nausea, vomit, cramping, if have renal insufficiency: fluid overload, hypermagnesemia, hyperphosphatemia Precautions: avoid in patients with renal impairment or chronic kidney issues; no for patients who are on Mg/Phosphate restricted diets; and Mg may lower absorption of some meds like mycophenolate, doxycycline, cipro BLACK BOX WARNING ON ORAL SODIUM PHOSPHATE: acute kidney impairment due to accumulation of sodium/phosphate; risk: >55, preexisting renal dysfunction, bowel obstruction, colitis, dehydration Advantage: cheap and fast Disadvantage: may be absorbed systemically after PO; electrolyte imbalance w/ extended use Recommended for: acute constipation, acute evacuation (colonoscopy) Patient counseling: Drink 8 oz of clear liquids with each dose. separate other meds by 2-4 hours

Stimulant Laxative: Castor Oil (MOA, Onset, Dose, Side Effects, Precautions)

MOA: not well understood; metabolized in small intestine to ricinoleic acid Onset: 2-6 hours Dose: 15-60 mL PO daily Side Effects: abdominal cramps, diarrhea, electrolyte imbalance Precautions: NO FOR PREGNANT WOMEN- MAY STIMULATE CONTRACTIONS; may cause erosion of intestinal lumen

Names/Dose of Saline Laxatives

Magnesium hydroxide (Milk of Magnesia): PO 15-45 mL/day once daily before bedtime or in divided doses Magnesium Citrate: Evac-Q-Mag (PO 15-45 mL/day once daily before bedtime or in divided doses) Sodium Phosphate: Fleet Saline Enema (PR 4.5oz enema as single dose- 1 bottle)

Names/Dose of Bulk Forming Agents

Metamucil- Psyllium Citrucel: methylcellulose Fibercon: Calcium polycarbophil Dose: 2-3 g/day: follow instructions on package

Names/Dose of Lubricating Agents

Mineral Oil: PO: 118mL PR (rectal) single use or 5-45 mL PO daily

Names/Dose of Hyperosmotic Agents

Miralax: PEG-3350 (PO)- 17 g/day Glycerin: Fleet suppository- 3g/day

Exclusions for self treatment

Rectal Bleeding, >1 week use of laxatives, if laxatives do not result in loose stool, abdominal pain/cramp, nausea/vomiting, symptoms for over 2 weeks

Constipation Complications

Rectal Prolapse Hemorrhoids Blood Pressure surges Fecal Impaction

Chronic Constipation Criteria

Rome III Criteria: in past 6 months, at least 3 months you have experienced at least 2 of the following: >25% of BM: lack of evacuation, obstruction, straining, hard and lumpy poo, manual maneuvers to poo; <3 BM/week, need laxatives

Treatment for opiate-induced constipation

Take 100-250mg once to twice/day along with stimulant laxatives. (if opiate is taken AS NEEDED, remember to ask if patient is actually taking it during episode of constipation!!)

Caution for all laxatives

Use lowest effective dose, do not use for more than 1 week, and use only when constipated (stop when there is loose bowel)

Symptoms of Constipation

incomplete evacuation, obstruction, nausea, headache, fatigue, hard and lumpy poo, straining, lack of urgency, abdominal cramping/discomfort

Bowel movement summary

peristaltic movement to move poo from sigmoidal colon to rectum --> abdominal wall muscles tighten and internal sphincter relaxes (feel like pooing). Valsava maneuver to poo, relax external sphincter and pelvic floor elevates --> expel poo!