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NR 565 Exam Final Study Guide, Exams of Nursing

A.T. Still University of Health Sciences (ATSU)Nursing

NR 565 Exam Final Study GuideNR 565 Exam Final Study Guide

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2022/2023

Available from 02/05/2023

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NR 565 Exam Final Study Guide
➢Antacids: weak bases that react with hydrochloric acid to form salt & water.
oUsed in the treatment of Hyperacidity, GERD, PUD, hyperphosphatemia, and calcium deficiency
oContain combinations of
▪metallic cation (aluminum, calcium, magnesium, and sodium)
▪and basic anion (hydroxide, bicarbonate, carbonate, citrate, and trisilicate)
➢Pharmacodynamics, Pharmacokinetics, Pharmacotherapeutics
oNeutralize Gastric Acidity (causes ^pH of the stomach and duodenal bulb)
oInhibit proteolytic activity of pepsin
oIncrease lower esophageal sphincter tone
oAcid-neutralizing capacity ANC varies between products expressed in mEqs
oIf ingested in a fasting state, antacids reduce acidity for approximately 20 to 40 minutes
oIf taken 1 hr after a meal, acidity is reduced for 2 to 3 hrs
oA second dose taken after a meal maintains reduced acidity for more than 4 hrs after the meal
oThe action of antacids occurs locally in the GI tract with minimal absorption, minimal metabolism
oALL antacids are contraindicated in the presence of severe abdominal pain of unknown cause, especially
if accompanied by fever
-HIGH SODIUM content: pts w/ HTN, CHF, marked renal failure, or on low-sodium diets need to use low sodium
preparation
-Concurrent administration with enteric-coated drugs, destroys the coating= alters absorption, ^ the risk for
adverse effects
-Administrations should be separated by at least 2 hours to decrease drug/drug interactions
1. Calcium based antacids: TUMS, Caltrate, Calcarb
•Prescribed to treat calcium deficient states, i.e. chronic renal failure, post-menopause, and osteoporosis
•Used to bind phosphates in CRF
•Require Vitamin D for absorption from the GI tract
•Excreted mainly in feces, 20% in urine
•ADR: Contraindicated in the presence of hypercalcemia and renal calculi
•Can cause constipation- increase bulk, fluids and mobility, stool softener
•Administered 30min- 1hr on empty stomach or 3hr after meals
•Should not be administered with food containing large amounts of oxalic acid (spinach, rhubarb),
or phytic acid (bran, cereals), they decrease the absorption of calcium
•Taking w/ foods containing phosphorus (milk, dairy) can lead to milk-alkali syndrome (N/V,
confusion, headache).
•Taking with acidic fruit juice improve absorption
2. Aluminum based: AlternaGEL, Amphojel, Mylanta
•Inhibit smooth muscle contraction and slow gastric emptying
•Used to bind phosphates in CRF
Aluminum is not easily
removed by dialysis b/c
it is bound to albumin
& transferrin = do not
cross dialysis
membrane
•Not absorbable with routine use
•Aluminum concentrated in the CNS
•Bind with phosphate and excreted in feces
•Prolonged use in patients with renal failure may result in dialysis osteomalacia
oAluminum deposits in bone and osteomalacia occurs
•Elevated aluminum tissue levels contribute to the development of dialysis encephalopathy
•Used to treat hyperphosphatemia in pts w/ renal failure & phosphate renal stone prevention
•Can cause constipation- increase bulk, fluids and mobility, stool softener
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NR 565 Exam Final Study Guide

➢ Antacids: weak bases that react with hydrochloric acid to form salt & water.

o Used in the treatment of Hyperacidity, GERD, PUD, hyperphosphatemia, and calcium deficiency

o Contain combinations of

▪ metallic cation (aluminum, calcium, magnesium, and sodium) ▪ and basic anion (hydroxide, bicarbonate, carbonate, citrate, and trisilicate) ➢ Pharmacodynamics, Pharmacokinetics, Pharmacotherapeutics

o Neutralize Gastric Acidity (causes ^pH of the stomach and duodenal bulb)

o Inhibit proteolytic activity of pepsin

o Increase lower esophageal sphincter tone

o Acid-neutralizing capacity ANC varies between products expressed in mEqs

o If ingested in a fasting state, antacids reduce acidity for approximately 20 to 40 minutes

o If taken 1 hr after a meal, acidity is reduced for 2 to 3 hrs

o A second dose taken after a meal maintains reduced acidity for more than 4 hrs after the meal

o The action of antacids occurs locally in the GI tract with minimal absorption, minimal metabolism

o ALL antacids are contraindicated in the presence of severe abdominal pain of unknown cause, especially

if accompanied by fever

  • HIGH SODIUM content: pts w/ HTN, CHF, marked renal failure, or on low-sodium diets need to use low sodium preparation -Concurrent administration with enteric-coated drugs, destroys the coating= alters absorption, ^ the risk for adverse effects -Administrations should be separated by at least 2 hours to decrease drug/drug interactions
  1. Calcium based antacids : TUMS, Caltrate, Calcarb
  • Prescribed to treat calcium deficient states, i.e. chronic renal failure, post-menopause, and osteoporosis
  • Used to bind phosphates in CRF
  • Require Vitamin D for absorption from the GI tract
  • Excreted mainly in feces, 20% in urine
  • ADR: Contraindicated in the presence of hypercalcemia and renal calculi
  • Can cause constipation- increase bulk, fluids and mobility, stool softener
  • Administered 30min- 1hr on empty stomach or 3hr after meals
  • Should not be administered with food containing large amounts of oxalic acid (spinach, rhubarb), or phytic acid (bran, cereals), they decrease the absorption of calcium
  • Taking w/ foods containing phosphorus (milk, dairy) can lead to milk-alkali syndrome (N/V, confusion, headache).
  • Taking with acidic fruit juice improve absorption
  1. Aluminum based: AlternaGEL, Amphojel, Mylanta
  • Inhibit smooth muscle contraction and slow gastric emptying
  • Used to bind phosphates in CRF Aluminum is not easily removed by dialysis b/c it is bound to albumin & transferrin = do not cross dialysis membrane
  • Not absorbable with routine use
  • Aluminum concentrated in the CNS
  • Bind with phosphate and excreted in feces
  • Prolonged use in patients with renal failure may result in dialysis osteomalacia o Aluminum deposits in bone and osteomalacia occurs
  • Elevated aluminum tissue levels contribute to the development of dialysis encephalopathy
  • Used to treat hyperphosphatemia in pts w/ renal failure & phosphate renal stone prevention
  • Can cause constipation- increase bulk, fluids and mobility, stool softener
  1. Magnesium based: Milk of mag, Maalox, Mylanta
    • Can be used to treat magnesium deficiencies from malnutrition, alcoholism, or mag-depleting drugs
    • Contraindicated in patients with renal failure & used with caution in pts with renal insufficiency The malfunctioning kidney cannot excrete magnesium= hypermagnesemia
  • Not absorbable with routine use
  • Excreted in the urine
  • Contraindicated in patients with renal failure, use with caution for patients with any degree of renal insufficiency o Malfunctioning kidney is unable to excrete magnesium and hypermagnesemia may result
  • Can cause diarrhea- increase fiber intake (Alkalosis may occur in renal impairment) Clinical Use and Dosing

➢ Antidiarrheals:

  • Diarrhea that lasts for less than 2 weeks is considered acute; if it lasts more than 2 weeks, it is considered chronic.
  • Pharmacodynamics, Pharmacokinetics
  • Three main classes absorbent preparations (kaolin and pectin (Kapectolin) and bismuth subsalicylate (Pepto- Bismol, Kaopectate Liquid), opiates (diphenoxylate with atropine (Lomotil), diphenoxin with atropine (Motofen), and loperamide (Imodium)) and anticholinergics (IBD)
  • Contraindications: Drugs that decrease gastric motility or delay intestinal transit time have induced toxic megacolon, especially in those with inflammatory bowel disease
  • All antidiarrheals (except Crofelemer) require cautious use in older adults and when there is r/f impaction
  • Older adults are especially sensitive to diphenoxylate or difenoxin r/t atropine and anticholinergic properties
  • Not recommended for children under 12, none of the antidiarrheals are safe for children under 2 years old
  • Antidiarrheals are contraindicated in the Tx of diarrhea in most children
  • Standard of care: oral rehydration therapy
  • ADRS Rebound constipation is the main adverse effect - Kaolin-pectin (kapectolin): Acute diarrhea
  • Kaolin is a clay-like powder that attracts and holds onto bacteria
  • Pectin thickens the stool by absorbing moisture
  • Used to treat simple diarrhea
  • Act locally in the bowel, not systemically absorbed
  • Pregnancy Category B - Bismuth subsalicylate (Pepto bismol): Acute diarrhea, travelers’ diarrhea ▪ Antisecretory and antimicrobial effects ▪ Also used as part of a multidrug regimen for H. pylori ▪ Undergoes chemical dissociation in GI, salicylate moiety is absorbed ▪ Salicylate is metabolized in the liver and more than 90% is excreted in urine ▪ Contraindicated in children or teenagers during or after recovery from chickenpox or flu-like illness ▪ Contraindicated for patients with ASA hypersensitivity ▪ For bismuth subsalicylate, additional reactions that all patients should be warned about are gray/black stools and black tongue, the results of the bismuth. Patients should be told to expect this reaction and that it does not indicate GI bleeding. ▪ Bismuth subsalicylate may potentiate the risk for toxicity if taken w/ aspirin ▪ R/f hypoglycemia in large doses with insulin or oral hypoglycemics
  • Crofelemer (fulyzaq): Symptomatic relief of noninfectious diarrhea in adult pts w/ HIV/AIDS on antiretroviral therapy ▪ Botanical blocking chloride secretion from the epithelial cells in the intestinal lumen, decreasing water loss and normalizing the flow of chloride and water in the intestinal tract ▪ Minimal absorption after PO administration ▪ Metabolism and excretion are not known ▪ In clinical trials more likely to have URI, bronchitis, and cough than placebo group ▪ Adverse GI effects flatulence, increased bilirubin, and nausea
  • diphenoxylate w/atropine (Lomotil): Acute diarrhea ▪ Constipating meperidine congener, lacks analgesic activity ▪ At high doses can produce euphoria and physical dependence ▪ Anticholinergics are useful only with inflammatory bowel disease ▪ Well absorbed from GI tract

▪ The atropine crosses the BBB (produces mild to moderate anticholinergic effects) ▪ Rapidly and extensively metabolized to diphenoxylic acid (it’s metabolite) ▪ Excreted in urine and feces ▪ The atropine component of diphenoxylate and difenoxin contraindicates their use in narrow- angle glaucoma and requires cautious use in prostatic hyperplasia. ▪ Children, especially those with Down syndrome have increased sensitivity to atropine ▪ Use with extreme caution in children, not recommended for use in children younger than 12 y/o ▪ Do not use with E. Coli, Salmonella, Shigella, or in pseudomembranous colitis ▪ ADRs: r/t atropine: anticholinergic effects (dry mouth, flushing, tachycardia, urinary retention) o Crosses BBB=dizziness, drowsiness, sedation, HA, euphoria, or depression ▪ Additive or potentiating CNS effects with other CNS depressants and additive anticholinergic effects with other drugs that share these effects

  • Difenoxin w/atropine (Motofen): Acute diarrhea9***** ▪ Anticholinergics are useful only with inflammatory bowel disease ▪ Rapidly metabolized to an inactive hydroxylated metabolite ▪ Excreted mainly as conjugates in urine and feces ▪ The atropine component of diphenoxylate and difenoxin contraindicates their use in narrow- angle glaucoma and requires cautious use in prostatic hyperplasia. ▪ Children, especially those with Down syndrome have increased sensitivity to atropine ▪ Use with extreme caution in children, not recommended for use in children younger than 12 y/o ▪ Do not use with E. Coli, Salmonella, Shigella, or in pseudomembranous colitis ▪ ADRs: r/t atropine: anticholinergic effects (dry mouth, flushing, tachycardia, urinary retention) o Crosses BBB=dizziness, drowsiness, sedation, HA, euphoria, or depression ▪ Additive or potentiating CNS effects with other CNS depressants and additive anticholinergic effects with other drugs that share these effects - Loperamide (Imodium): Acute diarrhea, travelers’ diarrhea, chronic diarrhea associated w/inflammatory bowel disease
    • Binds to opiate receptors of the intestinal wall, slows gastric motility
    • Reduces fecal volume, increases viscosity and bulk, diminishes loss of fluid and electrolytes
    • Does not cross BBB, limited CNS ADRs
    • Partially metabolized by the liver and undergoes enterohepatic recirculation to be completely metabolized
    • Eliminated in feces
    • ADRs: r/t atropine: anticholinergic effects (dry mouth, flushing, tachycardia, urinary retention) o To a lesser degree than diphenoxylate and difenoxin o Dizziness and drowsiness (less CNS effects than difenoxin or diphenoxylate
    • Additive or potentiating CNS effects with other CNS depressants and additive anticholinergic effects with other drugs that share these effects Pharmacotherapeutics
    • Precaution and contraindications
    • Drugs that reduce intestinal motility or delay intestinal transit time may cause toxic megacolon, especially in IBD
    • Diphenoxylate with atropine difenoxin with atropine, and loperamide should be used cautiously in IBD o D/C if ABD distension occurs
    • Use Diphenoxylate with atropine difenoxin with atropine, and loperamide use with caution in advanced hepatorenal disease and in all patients with abnormal LFTs (hepatic coma may occur)
    • Atropine: contraindicated in narrow-angle glaucoma and requires cautious use in prostatic hyperplasia
    • Children (especially those with Downs syndrome) have increased sensitivity to atropine
    • Clinical Use and Dosing
  • Drug interactions may occur, especially with diphenoxylate and loperamide
  • Do not take any OTC antidiarrheal before contacting your provider if taking digoxin, cephalosporin antimicrobials, warfarin or heparin, or CNS depressants (including ETOH)
  • R/f salicylate poisoning if taking ASA and bismuth subsalicylate
  • R/f rebound constipation
  • Stop drug when s/s of diarrhea are reduced
  • Bismuth subsalicylate can turn the tongue and stools gray/black
  • Drugs with atropine: dry mouth, flushing, tachycardia, and urinary retention
  • Loperamide also exhibits these reactions but to a lesser degree, add fiber and use oral rehydrating solutions
  • GHWT
  • Bland food diet, remove milk, could it be lactose intolerance?

➢ Cytoprotective Agents:

o Agents used to treat or prevent ulcer formation

o Two drugs sucralfate (Carafate) and misoprostol (Cytotec)

❖ Pt should report onset of black tarry stools or severe abdominal pain, which may indicate

treatment failure and GI bleeding Sucralfate (Carafate):

  • Pharmacodynamics- Basic aluminum salt that binds to necrotic ulcer tissue where it acts as a barrier to acid, pepsin, and bile salts. o Action is largely topical, no acid-neutralizing activity, little is absorbed o May directly absorb bile salts and stimulate endogenous prostaglandin synthesis (formation of protective mucosa)
  • Pharmacokinetics
  • Minimal absorption, action is largely topical
  • Essentially not absorbed, 90% excreted in feces
  • Pharmacotherapeutics
  • No specific precautions or contraindications
  • Pregnancy Category B
  • Safety in children not established
  • ADRs Minor and rare: constipation, dizziness, gastric discomfort
  • Drug/Drug interactions : Decrease absorption of other drugs
  • Misoprostol: less effective for Tx of duodenal ulcers from other causes o Off-label: in doses >400mcg/day, Tx for duodenal ulcers not responsive to H2Ras Rational Drug Selection
  • Sucralfate: drug of choice for women of childbearing age
  • Sucralfate preferred over misoprostol for treatment of active duodenal ulcers not caused by NSAIDs Monitoring
  • No specific monitoring parameters
  • Negative pregnancy test for misoprostol Patient Education
  • Take exactly as prescribed
  • Sucralfate on an empty stomach, Sucralfate is given for 4 to 8 weeks, increase fluid intake, dietary bulk, and exercise to reduce incidence of constipation
  • Misoprostol with food, Misoprostol given for the duration of NSAID therapy, can cause diarrhea, if persists x1WK notify provider
  • Continue therapy even if you feel better

➢ Antiemetics:

Drug classes with antiemetic properties: antihistamines, phenothiazines, sedative hypnotics, cannabinoids, 5-HT receptor antagonist, anticholinergics, and a substance P/neurokinin 1 receptor antagonist Antihistamines: dimenhydrinate (Dramamine), diphenhydramine (Benadryl), hydroxyzine (Vistaril), meclizine (Antivert)

  • Pharmacodynamics: Antihistamines with significant antiemetic activity have strong anticholinergic effects as well as histamine 1 blocking effects
  • MOA: Bind to central cholinergic receptors to produce antiemetic effects
  • especially with motion sickness due to the depression of conduction in the vestibulocerebellar pathway
  • Pharmacokinetics: All the antiemetic drugs (except for TD scopolamine) are well absorbed after PO administration
  • Pharmacotherapeutics: Cautious use in narrow-angle glaucoma, seizure disorders, pyloric obstruction, hyperthyroidism, CVD, and prostatic hypertrophy
  • Contraindicated in severe liver disease r/t extensive liver metabolism
  • Cautious use in the elderly, dose reductions may be needed
  • Dimenhydrinate and diphenhydramine are Pregnancy Category B and safe for use in children
  • Meclizine is pregnancy Category B (safety and efficacy in children less than 12 not established)
  • Hydroxyzine Pregnancy Category C, has been used safely during labor (safety in children or lactation not established) ADRs: Common adverse reactions : drowsiness, dry mouth, blurred vision & urinary retention
  • Paradoxical excitation may occur in children
  • Drug/Drug: additive CNS depression with other drugs that produce CNS depression and additive anticholinergic effects with other drugs that have anticholinergic effects or adverse reactions Phenothiazines: prochlorperazine (Compazine), perphenazine, promethazine (Phenergan)
  • Pharmacodynamics: block dopamine receptors in the chemoreceptor trigger zone (CTZ)
  • Also bind to and block cholinergic, alpha 1 adrenergic, and histamine 1 receptors
  • Use as antiemetics is limited due to sedating and EPM effects - Pharmacotherapeutics: Produce extrapyramidal reaction **Contraindicated in Parkinson’s Disease
  • Contraindicated in narrow-angle glaucoma, bone marrow depression, and sever CVD or hepatic disease**
  • Cautious use in respiratory impairment cause by acute pulmonary infection or chronic respiratory disorders (asthma or emphysema)
  • May lead to the development of “silent pneumonia”
  • Suppress cough reflex, aspiration of vomitus is possible
  • Use with caution in those with r/f aspiration
  • Pregnancy Category C
  • Children of all ages are more prone to developing extrapyramidal reactions
  • Prochlorperazine: avoided in children younger than 5 r/t extrapyramidal reactions
  • R/f respiratory depression and sudden death in children 2 years of age or older
  • Adverse reactions: drowsiness, (extrapyramidal reactions) dystonia, akathisia, tardive dyskinesia o Dry mouth, dry eyes, blurred vision, constipation, and urinary retention o ability to mask post-surgical and neurological conditions o potential for agranulocytosis and blood dyscrasias 4-10 weeks after initiation o can cause urine to turn pink to reddish brown (does not indicate hematuria)
  • Promethazine Black Box Warning: Fatal respiratory depression in children younger than 2 years old
  • Drug/Drug: additive CNS depression with other drugs that produce CNS depression and additive anticholinergic effects with other drugs that have anticholinergic effects or adverse reactions
  • Additive hypotensive effects with antihypertensive agents or acute ingestion of ETOH
  • Concurrent administration of lithium increases r/f extrapyramidal reactions
  • May mask s/s of lithium toxicity
  • Antithyroid agents increase r/f agranulocytosis Cabbabinoid: dronabinol (Marinol)

- Concurrent use of Aprepitant and pimozide, terfenadine, astemizole, or cisapride is contraindicated due to potentially life-threatening reactions Misc.: trimethobenzamide (Tigan)

  • Pharmacodynamics: Inhibits emetic stimulation of the CTZ Rational Drug Selection: Treatment of Nausea and Vomiting Due to Drugs or Gastroenteritis
  • Often improves with Tx using an antiemetic
  • 5-HT3 receptor antagonists: low side-effect profile and tolerance
  • Phenothiazines: also, a good initial and short-term treatment choice, not for children
  • Trimethobenzamide: also, effective
  • Antihistamines: can be used, less serious ADRs, better for longer term applications
  • Dronabinol: only approved for use in chemotherapy associated NV and appetite stimulation
  • Aprepitant: Approved for post-operative NV and in conjunction with other antiemetic agents for prevention of acute and delayed NV associated with initial and repeated doses of emetogenic CA chemo Motion sickness:
  • Antihistamines are useful r/t action on vestibular system and CTZ, rapid onset of action and prolonged effect
  • Dimenhydrinate and meclizine: the most used
  • Meclizine is also used to treat vertigo
  • TD scopolamine: indicated for prevention of NV associated with motion sickness in adults and is commonly used in patients on ships Monitoring:
  • When used as a single dose or very short-term, no specific monitoring required
  • If Tx for longer than a few days: following monitoring parameters are suggested
  • Promethazine has been associated with bone marrow depression (CBC prior to initiating therapy)
  • Phenothiazines associated with blood dyscrasias that occur between week 4-10 of therapy o CBC prior to initiating therapy and after 4 weeks Patient Education
  • Motion sickness: take 1 to 2 hrs prior to departure (except for ER-12 hrs prior)
  • ADRs: drowsiness, dry mouth, dry eyes, constipation, and urinary retention
  • Phenothiazines: turns urine pink to reddish brown: this is not hematuria

Do not inhibit ➢ Histamine-2 receptor antagonists: H2Ras

o Histamine 2 blockers aka histamine 2 antagonists (H2Ras)

acetylcholine, so they reduce gastric acid secretion by only 35%-50%

Cimetidine (Tagamet), Famotidine (Pepcid), Nizatidine (Axid), Ranitidine (Zantac)

  • Used to reduce gastric acid in NPO pts for prophylaxis and management of duodenal and gastric ulcers and GERD (not first-line treatment of GERD), if no esophageal erosive disease is present H2RA’s can be used for maintenance therapy for relief of GERD symptoms
  • Also used for heart burn, acid indigestion and “sour stomach”
  • Pharmacodynamics: MOA: Inhibit acid secretion by gastric parietal cells through a reversible blockade of histamine at H2 receptors
  • potent inhibitors of all phases of gastric acid secretion, including muscarinic agonists and gastrin
  • Effect volume and H ion concentration of gastric juice, gastric emptying, and lower esophageal sphincter pressure (each drug to varying degrees) o Cimetidine, ranitidine, and famotidine have no effect on gastric emptying o Cimetidine and famotidine have no effect on lower esophageal sphincter pressure o Ranitidine, nizatidine, and famotidine have little or no effect on fasting or postprandial serum gastrin o Ranitidine does not affect pepsin secretion or pentagastrin-stimulated IF secretion
  • Pharmacokinetics o All drugs are well absorbed with PO administration

o All are metabolized to differing degrees by the CYP450 system and excreted in differing percentages unchanged in urine

  • Pharmacotherapeutics
  • Caution: Renal impairment (dosage adjustments, r/f CNS ADRs), Elderly (due to decrease in renal function)
  • Contraindicated: Nizatidine and Ranitidine DO NOT rx for patients w. hx of liver disease (causes hepatocellular injury, hepatitis) elevated ALT AST
  • Pregnancy Category B, excreted in breast milk, use caution in breastfeeding mothers
  • Famotidine is labeled safe for infants & neonates (has caused agitation, stopped when drug d/ced)
  • Cimetidine can cause gynecomastia & impotence o CNS reversible reactions (mental confusion, agitation, psychosis, depression, and disorientation)
  • Hematological adverse reactions include agranulocytosis, granulocytopenia, thrombocytopenia, and aplastic anemia (rare)
  • Less Common side effects: drowsiness, dizziness, constipation (increase fiber and fluid intake), or diarrhea & nausea
  • Drug/Drug Interactions : Related to CYP450 system o Cimetidine is most problematic (metabolized by CYP1A2, CYP2C9, and CYP2D6) o Other drugs metabolism inhibited by cimetidine (r/f increased serum levels and toxicity
  • Clinical Use and Dosing GERD-most effective if used as on demand therapy for symptoms relief o Tachyphylaxis: Not first line therapy to treat GERD o If not erosive disease, may be used as maintenance therapy after PPI treatment o Infants and children have been successfully treated however no longer recommends H2Ras as empiric treatment in infants
  • Rational Drug Selection o No specific drug is preferred over another for effectiveness o Consider costs
  • Monitoring o LFTs r/t potential for hepatocellular damage o Renal impairment: renal function assessment prior to initiation of therapy
  • Patient Education
  • Should be taken w/ meals or immediately after & at bedtime, daily doses are best @ bedtime,
  • take 1 hour away from other drugs,
  • & two hours away from sucralfate
  • OTC preparations should not be taken for more than 2 wks without consulting healthcare provider
  • Report black tarry stools- may indicate GI bleeding.
  • Sore throat, diarrhea, rash, confusion, or hallucinations should be reported promptly (might need dosage adjustment or discontinuation),
  • advise pt to stop smoking (interferes with absorption of H2RA & increases gastric secretion)
  • Prokinetics: metoclopramide (Reglan) o AKA gastrointestinal stimulants o Do not stimulate gastric, biliary, or pancreatic secretions o Used to treat gastroparesis associated with DM, GERD, and emesis with chemotherapy Pharmacodynamics: MOA: Stimulates motility in the upper GI tract, ▪ increases tone and amplitude of gastric contractions, ▪ relaxes the pyloric sphincter and duodenal bulb, ▪ and increases peristalsis of the duodenum and jejunum, ▪ resulting in accelerated gastric emptying and increased speed of gastric transit - Improves gastroesophageal reflux disease symptoms by increasing lower esophageal tone - Also is a dopamine receptor agonist in the CNS, including the chemotherapy trigger zone leading to prevention of emesis - Actions similar to phenothiazines: Produces sedation and may cause tardive dyskinesia or EPS - Induces release of prolactin and transient increases of aldosterone Pharmacokinetics - Well absorbed after PO administration - Injectable formulation is available - High bioavailability, low protein binding - Widely distributed, crosses BBB and placenta, enters breast milk (greater than plasma) - Minimally Metabolized by the liver, liver function is not an issue - Excreted in urine (clearance is affected by renal function) - Renal impairment requires dose adjustment: dose cut in half CCr < Pharmacotherapeutics - BLACK BOX WARNING : risk for developing tardive dyskinesia and parkinsonian-like symptoms, the risk increases the longer it’s in use, treatment should not exceed 12 weeks and be discontinued immediately if signs of movement disorder, Report involuntary movement of the eyes, face, or limbs immediately - Contrindicated : in the presence of disorders in which stimulation of GI motility is dangerous (GI hemorrhage, mechanical obstruction, new surgery on the GI tract, or perforation), - dopamine- associated activity affects the CNS & can cause depression (mild- severe w. suicidal ideation), use with caution - Contraindicated in pt.s w. pheochromocytoma b/c the drug can cause hypertensive crisis - Safe to administer to pt .s with hx of impaired hepatic function if renal function is normal - Safety and effectiveness not established in infants and children o EPS is more common in children, use with caution ADRs - Most serious reaction is EPS (dystonic reaction and tardive dyskinesia and parkinsonian- like symptoms d/c in pt. exhibiting movement d/o - Neuroleptic malignant syndrome - More common: Depression, dizziness, diarrhea, and hypoglycemia in DM - Less common: galactorrhea, amenorrhea, gynecomastia, impotence secondary to hyperprolactinemia, and fluid retention r/t elevations in aldosterone - Incidence of ADRs correlated with the dose and duration of therapy Drug interactions : Largely related to its cholinergic and dopaminergic activity