Antiemetic, Antidiarrheal, Laxatives

• Antiemetics


  Drugs that can be purchased over the counter and used to prevent motion sickness
• Antiemetics


  • dimenhydrinate (Dramamine)
  • cyclizine hydrochloride (Marezine)
  • meclizine hydrochloride (Benadryl)
• Prescription antiemetics


  • antihistamine
  • anticholenergics
  • benzodiazepines
  • cannabinnoids
  • dopamine antagonist
  • miscellaneous
  • serotonin antagonist
  • glucocorticoids
• Antiemetic (Antihistamine)


  Hydroxyzine HCl
• Antiemetics


  • Suppression of subcortical areas of the CNS
  • Antihistaminic, analgesic, antispasmodic, antiemetic, mild anti secretory
• Uncomplicated vomiting can contribute to Reye's syndrome
• Side effects of antiemetics


  • CNS: drowsiness
  • GI: dry mouth
  • Hypersensitivity: dyspnea
• Nursing implications for antiemetics

  • Give drug deep IM
  • Underlying cause of vomiting to identify
  • Monitor for adverse reactions such as dizziness, sedation, drowsiness
  • History of allergy to the drug to monitor
  • Assess for skin color, lesions, texture
  • Avoid alcohol which can increase drug effect
  • Report difficulty of breathing, tremors
• Anticholinergic (Scopolamine)


  • Mediates the interference with cholinergic impulses to the vomiting center
  • Unclear action to motion sickness
  • Has sedative effect
  • Blocks acetylcholine at muscarinic cholinergic receptors which depress salivary secretions and bronchial secretions
• Therapeutic uses of anticholinergics

  • Prevention and control of nausea and vomiting
  • Adjunct therapy with antacids & H2 antihistamines in peptic ulcer
• Contraindications for anticholinergics


  • Myocardial ischemia
  • Allergy to drug
  • Glaucoma
  • Ileus, intestinal atony
  • COPD
  • Caution use in Down's Syndrome
• Side effects of anticholinergics


  • CNS: pupil dilation, photophobia, headache, drowsiness, blurred vision
  • GI: dry mouth, urinary hesitancy, constipation
  • CV: palpitations, tachycardia
• Nursing implications for anticholinergics


  • Hx of allergy, glaucoma, obstruction to establish
  • Assess for skin color, lesions, bilateral grip strength, urine output
  • Avoid alcohol
  • Skin rash and other side effects to report 30 mins before meals intake
• Phenothiazines


  Depress parts of the brain involving wakefulness and emesis
• Therapeutic uses of phenothiazines


  • Control nausea and vomiting
  • Anti psychotic
  • Relief of pre-op restlessness and apprehension
• Contraindications for phenothiazines


  • Bone marrow depression
  • Antiemetic drug can mask s/s of Reye's Syndrome
  • Severe hypotension
  • Allergy
  • Respiratory disorders
  • Renal and prostate problems
• Side effects of phenothiazines


  • CNS: vertigo, insomia, drowsiness
  • GI: dry mouth, salivation, nausea vomiting
  • CV: orthostatic hypotension
  • Respi: brochospasm, laryngospasms
  • Hema: eosinophilia, leukopenia, leukocytosis
  • GU: urinary retention
  • EENT: photophobia
• Nursing implications for phenothiazines


  • Protect oral concentration from light
  • Do not allow to chew sustained release drug
  • Monitor CBC, refer if WBC is high
  • Dilute oral concentrate just before administration w/ 60 ml
  • Recumbent position for 1/2 hr. to avoid orthostatic hypotension
  • Aspiration precaution
  • Withdraw drugs gradually after use
  • Elderly are prone to dehydration and decreased sensation for thirst
  • Renal function test to monitor
• Benzodiazepine (Lorazepam)


  Potentiate the effects of GABA an inhibitory transmitter
• Contraindications for benzodiazepines


  • Hypersensitivity to the drug
  • Impaired liver
  • Narrow angle glaucoma
• Side effects of benzodiazepines


  • CNS: transient mild drowsiness, depression, lethargy
  • GI: constipation, diarrhea, dry mouth
  • CV: bradycardia, tachycardia, CV collapse, hypotension
  • Hema: elevated LDH, Alkaline phosphatase, Blood dyscrasias SGOT
  • EENT: visual and auditory disturbances
  • Derma: Urticaria, Pruritus
• Nursing implications for benzodiazepines


  • Do not stop prescribed drug without doctor consultation
  • Reports severe dizziness and drowsiness
  • Ambulatory patient to monitor while taking the drug
  • Monitor side effects
  • Narcotic analgesics to reduce on pt. taking the drug
• Serotonin Receptor Antagonist


  Indications: Chemotherapy induced nausea
• Cannabinoids


  Indications: Chemotherapy induced nausea
• Emetics


  Drugs used to induce vomiting
• Antidiarrheals


  Drugs for treating diarrhea and decreasing hypermotility
• Classification of antidiarrheals


  • Opiates / opiate related agents
  • Somatostatin Analog
  • Adsorbents
  • Miscellaneous Antidiarrheal
• Opiates and opiate-related agents


  • Decrease intestinal motility thereby decreasing peristalsis
  • Constipation is a common side effect
  • Codeine is an example
  • Opiates are frequently combined with other antidiarrheal agents
  • Opium antidiarrheals can cause CNS depression when taken with alcohol, sedatives, or tranquilizers
  • The duration of action of opiates is approximately 2 hours
• Diphenoxylate with atropine


  An opiate that has less potential for causing drug dependence than other opiates such as codeine
• Loperamide


  Structurally related to diphenoxylate but causes less CNS depression than diphenoxylate and difenoxin
• Adsorbents


  • Act by coating the wall of the GI tract and adsorbing bacteria or toxins that cause diarrhea
  • Adsorbent antidiarrheals include kaolin and pectin
  • Bismuth subsalicylate is considered an adsorbent because it adsorbs bacterial toxins
• Nursing interventions for antidiarrheals


  • Record vital signs
  • Report tachycardia or systolic blood pressure decreases of 10 to 15 mm Hg
  • Monitor respirations
  • Monitor frequency of bowel movements and bowel sounds
  • Notify a health care provider if intestinal hypoactivity occurs
  • Check for signs and symptoms of dehydration
  • Fluid replacement may be necessary
  • Check serum electrolytes with prolonged diarrhea
  • Administer antidiarrheals cautiously to pregnant patients and those with glaucoma, liver disorders, or ulcerative colitis
  • Recognize that a drug may need to be withheld if diarrhea continues for more than 48 hours or acute abdominal pain develops
• Laxatives


  Drugs used to eliminate fecal matter by softening the stool
• Cathartics


  Drugs that facilitate soft to watery stool with some cramping
• Types of laxatives


  • Stimulants (contact or irritants)
  • Emollients (stool softener)
  • Bulk forming
  • Osmotic (saline)
• Stimulant (contact) laxatives


  • Increase peristalsis by irritating sensory nerve endings in the intestinal mucosa
  • Types include those that contain bisacodyl, senna, and castor oil (purgative)
  • Bisacodyl is the most frequently used and abused laxative and can be purchased OTC
  • Bisacodyl and several others of these drugs are used to empty the bowel before diagnostic tests (barium enema)
• Nursing interventions for laxatives


  • Monitor fluid intake and output
  • Note signs and symptoms of fluid and electrolyte imbalances that may result from watery stools
  • Habitual use of laxatives can cause fluid volume deficit, electrolyte losses, and loss of the urge to defecate
• Emollients (stool softeners)


  • Lubricants and stool softeners (surface-acting or wetting drugs) used to prevent constipation
  • Decrease straining during defecation
  • Lubricants such as mineral oil increase water retention in the stool
  • Mineral oil absorbs the essential fat-soluble vitamins A, D, E, and K
  • Some of the minerals can be absorbed into the lymphatic system
• Bulk-forming laxatives


  • Natural fibrous substances that promote large, soft stools by absorbing water into the intestine, increasing fecal bulk and peristalsis
  • Nonabsorbable
  • Defecation usually occurs within 8 to 24 hours; however, it may take up to 3 days after drug therapy is started for the stool to be soft and well formed
  • Powdered bulk-forming laxatives, which sometimes come in flavored and sugar-free forms, should be mixed in a glass of water or juice, stirred, drunk immediately, and followed by a half to a full glass of water
  • Polycarbophil, polyethylene glycol, methylcellulose, and psyllium are examples
• Osmotic (saline) laxatives


  • Hyperosmolar laxatives that include salts or saline products, lactulose, and glycerin
  • Saline products consist of sodium or magnesium, and a small amount is systemically absorbed
  • Serum electrolytes should be monitored to avoid electrolyte imbalance
  • Osmotic laxatives contain electrolyte salts, including sodium salts (sodium phosphate or Phospho-Soda, sodium biphosphate) and magnesium salts (magnesium hydroxide [Milk of Magnesia], magnesium citrate)
  • Lactulose, another saline laxative that is not absorbed, draws water into the intestines to form a soft stool
  • Decreases the serum ammonia level and is useful in liver diseases, such as cirrhosis