N/V/C/D Flashcards
What are some causes of GI irritation? 9
GI irritation Motion sickness Vestibular disease Hormone disturbance Drugs and radiation Exogenous toxins Pain Psychogenic factors Intracranial pathology
How else to N/V present clinically besides N/V
*Dehydration can occur as a result of vomiting(Pinching skin takes longer to go down)
Increased thirst and dry mouth.
Less frequent urination
Tachycardia
What are 3 nonpharm therapies for NV
Rehydrate- Oral rehydration Solutions Avoid dairy BRAT diet- 24 hours after fluid diet Banana Rice Apple Sauce Toast (Dry)
What are the 4 types of pharm therapy for N/V?
5-HT3 Antagonists
Dopamine Antagonists
Antihistamines
Cannabinoids
Name 3 types of 5-HT3 antagonists and what is the drug of choice for NV?
Ondansetron (Zofran) - DOC
Granisetron (Kytril)
Dolasetron (Anzemet)
What is the MOA of 5-HT3 antagonist?
Antagonism of the 5-HT3 receptor in the chemo-receptor trigger zone (CTZ)
What are the ROA for 5-HT3 Antagonists?
Oral, rectal, IM, IV
What are the 2 Indications of 5-HT3 antagonists?
Treatment and prevention of postoperative N/V
Chemotherapy-induced N/V
What are the ADRs of the 4 5-HT3 antagonists?
HA
Dizziness
Diarrhea
Abdominal pain
What are 3 examples of DA antagonists?
Metoclopramide (reglan)
Trimethobenzamide (Tigan)
Phenothiazines - Prochlorperazine (Compazine
what are the 3 MOA of DA antagonists?
one is specific for high dose of Metoclopramide
Antagonist of D2 receptors in the CTZ
At higher doses metoclopramide also blocks 5-HT3 receptors
Also promote gastric emptying and small intestine peristalsis—prokinetic effects.
5 contraind for DA Antagonists
GI—hemorrhage, obstruction or perforation Cautiously in patients w/depression Pheochromocytoma Seizure Use very cautiously in children
ADRs of DA antagonists?
Extrapyramidal effects
Restlessness, anxiety, drowsiness, fatigue, hallucinations
CV—HTN, HPOTN, AV block, bradycardia
Agranulocytosis
What is one antihistamine used in NV?
Promethazine (Phenergan)
What are the ROA of Promethazine?
IV PO IM PR
What are 2 MOA of Promethazine?
Block H1 effectiveness appear to be with motion sickness and vestibulochochlear disease
Antagonist of D2 receptors in the CTZ
What are the ADRs of antihistamines?
dry mouth, dizziness etc.
Parkinsonian symptoms (dyskinesia, dystonias, akathisia)
Neuroleptic malignant syndrome
Blood dyscrasias
In what conditions should you use caution in with promethazine? 3
BPH
Urinary retention
glaucoma
What is a cannabinoid used in NV
Dronabinol (Marinol)
What is the MOA of Dronabinol
Not well definded
What are the 3 ADRs of Dronabinol?
Drowsiness. sedation, and increased appetite
What 2 things does normal motility do in the intestines?
Acts to mix bowel contents thoroughly
To propel them in a caudal direction
Regulation of normal intestinal motility is by? 2
Neuronal
Hormonal
What nerve influences motility and what does it do?
The vagus nerve of the intestinal (enteric) system
Stimulates peristaltic movements
Relaxes digestive sphincters
Promotes GI secretion
What are the 5 classes of drugs that effect GI motility?
Laxatives Antidiarrheal Agents Prokinetic Agents Antiemetic Agents Antispasmodics
What is the Medical Definition of Constipation?
2 or more of the following: Straining > 25% of time Lumpy or hard stools > 25% of time Feeling of incomplete evacuation > 25% of time 2 or fewer BM in 1 week
What Metabolic diseases may cause constipation? 4
Hypothyroid, hypercalcemia, hypokalemia, diabetes
What 3 GI d/o may cause constipation?
Tumors, IBS, Diverticulitis
what 3 neurogenic d/o may cause constipation?
Trauma to brain/spinal cord, CNS tumor, Parkinson’s
What 6 meds may cause constipation?
Opiates Ca and Al antacids Iron Calcium channel blockers Clonidine Anticholinergics (Antihistamines, antiparkinsonians, TCA)
what are the 3 best ways to prevent constipation?
Drink plenty of water and fluids (“P” juices (pear, prune, peach))
Adequate exercise (Do not hold it (water will be reabsorbed and stools will harder))
High fiber diet (insol and sol) -
What does insol fiber do for constipation? 2 ex
Insoluble-shorten intestinal transit time and increase stool bulk.
Whole grains
Bran
What does sol fiber due for constipation
more moist stool and less effect on transit time.
Fresh fruits
Fresh vegetables
what do laxatives do? (2)
Drugs used to hasten transit time in the gut and encourage defecation.
Drugs are also used to clear the bowel prior to medical and surgical procedures.
what are 6 types of laxatives?
Bulk-Forming Laxatives Emollients and Lubricants Saline Cathartics Osmotic Laxatives Stimulant Laxatives
what are 3 times of bulk-forming laxatives?
Psyllium (Metamucil), Methylcellulose (Citrucel), Polycarbophil (Fibercon)
when is bulk-forming laxative onset time?
2-3days
what is the MOA of bulk-formong laxatives? (what is very imp to do along with these)
Increases the volume of the non-absorbable solid residue with water, distending the colon and stimulating peristaltic activity increasing the rate of colonic transit
(Adequate fluid intake is very important with these agents)
what is the 1st line for bedridden or geriatric with chronic constipation, and in Pregnancy?
bulk forming laxatives
What are the 3 contraindications for bulk-forming laxatives?
Patients with stenosis
Ulceration or adhesions
Fecal obstruction
what are the ADRs of Bulk forming laxatives? 3
flatulence, abdominal distension, gastrointestinal obstruction
What are drug interactions with bulk forming laxatives? what is the proper way to take other meds and bulk-forming lax?
Binds drugs & reduces absorption—separate from other medication administration.
take med 1st-wait 2 hrs then lax
take lax 1st-wait 4 hrs to take med
What are 3 other uses of bulk forming laxatives?
The ability of these agents to absorb water makes them useful for relieving symptoms of mild diarrhea.
Several months use can relieve symptoms of irritable bowel syndrome
Lowering cholesterol
what is one example of an emollient?
Docusate sodium (Colace)
what are the indications for emollients? DOC for?
To avoid straining
After MI, rectal surgery, opiates
1st line Pregnant women (along with bulk forming)
Onset of emollient is?
1-3 days
What is the MOA of emollients?
surfactant brings water into stool, facilitates mixing of aqueous and fatty materials within intestine, increase H20 and electrolyte secretion in small/ large bowel
what are contraindications for emollients?
Fecal Impaction
Signs and symptoms of appendicitis
What is an example of Lubricant used for constipation?
Mineral Oil
What is discouraged for mineral oil?
Chronic Use
What is Mineral Oil used for?
mainly for prevention
To avoid straining
After MI, rectal surgery
What is the Onset of mineral oil?
6hr-3days
what is the MOA of mineral oil?
coats stool (allows easier passage), inhibits colonic absorption of water
what are the cautions of mineral oil use? 4
Avoid in elderly, aspiration risk and decrease absorption of fat-soluble vitamins (DEAK)
May leak from anal sphincter
What are 2 examples of osmotic agents used for constipation?
Lactulose and sorbitol
What is lactulose’s MOA
disaccharide that is metabolized by bacteria in the colon to low-molecular weight acids = osmotic effect
what is lactulose NOT considered?
1st line agent in constipation
What are ADRs of lactulose?
May result in flatulence, cramps, electrolyte imbalances
What is lactulose more commonly used for (other than const)
More commonly used in patients with hepatic encephalopathy
what is the onset of lactulose
Oral dose softens stool in 1-3 days
what is sorbitols MOA
monosaccharide creates an osmotic gradient when used as a 70% solution
what is an ADR of sorbitol
hyperglycemia
what is the onset for sorbitol?
1-3days
What are 4 examples of saline cathartics used for diarrhea?
Magnesium hydroxide (Milk of Magnesia), magnesium sulfate (Epsom salts), sodium phosphate (Fleets Enema), magnesium citrate (Citrate of Magnesia)
What is the onset of saline cathartics?
30min-6hr (oral), 5-30min (rectal)
What is the MOA of cathartics?
Mg++ or Na+ salts are poorly absorbed; they increase the water content of the bowel through osmosis
What are 3 contraindications for cathartics
impaired renal function Mg and Na accumulation, CHF, no sodium for HTN pts
What is the MOA of glycerin suppository?
osmotic cation in rectum
Onset of glycerin suppository?
<30mins
What might glycerin suppository cause?
Rectal irritation
Indications for glycerin suppository
Very safe laxative/ Can be used in children
Intermittent use
Example are 2 ex of glycerin/hyperosmotic?
Polyethylene glycol (Miralax) (PEG, GoLYTELY)
How do you use Miralax
17g mixed in water or juice, usually 2 weeks duration, chronic use OK
what is the onset of miralax?
1-3days
what is the MOA of miralax?
osmotic
what is the indication for miralax?
Relatively safe and OK in children
What is the indication for PEG, GoLYTELY
for colonic cleansing before diagnostic procedures
what is the onset of action of PEG, GoLYTELY
1hr after initiation
what is the MOA of PEG, GoLYTELY
osmotic agent that causes retention of water resulting in softer stool and more frequent defecation
how do you take PEG, GoLYTELY
4 liters over 3 hrs (8oz glass every 10 minutes), not for chronic use
what pts should avoid use of PEG, GoLYTELY
Avoid in patients with intestinal obstruction
what are 2 stimulant laxatives?
Diphenelymethane deriv (bidacodyl (dulcolax)) Anthraquinone lax (senna (senokot))
what is the MOA of Bisacodyl (Dulcolax)
MOA stimulate nerve plexus of colon
who may take Bisacodyl (Dulcolax)
> 12y/o
what is the onset of Bisacodyl (Dulcolax)
Onset: 6-8hr (PO); 1-6h (PR)
when should you not take Bisacodyl (Dulcolax)
Should not take within 1 hour of antacids, milk or milk products
what are 3 ADRs of Bisacodyl (Dulcolax)
Intestinal cramps
Can cause fluid and electrolyte inbalance.
Pink colored urine and feces
what can long term use of Bisacodyl (Dulcolax) cause?
Could cause damage to the nerve plexi
Resulting in deterioration of intestinal function
Atonic colon
what is Senna (Senokot)?
Anthraquinone laxative
what is the MOA of Senna (Senokot)
Increased peristalsis
what is Senna (Senokot) coformulated with
docusate
who can take Senna (Senokot)
> 12y/o
what is the onset of Senna (Senokot)
6-12 hr
what are the ADRs of Senna (Senokot) 2
Yellow-brown to red colored urine
Large doses can produce nephritis
what can long term use of Senna (Senokot) cause?
Could cause damage to the nerve plexi
Resulting in deterioration of intestinal function
Atonic colon
what are the contraind of Senna (Senokot) -2
Pregnancy and acute intestinal inflammation
what is the MOA if Lubiprostone (Amitiza)
chloride-channel activator…works by increasing fluid secretion locally in the small intestine by activating the ClC-2 chloride channel
what are the ADRs of Lubiprostone (Amitiza)
Nausea and diarrhea
what is the onset of Lubiprostone (Amitiza)
1d-1wk or more
what are the contraind of Lubiprostone (Amitiza)
Intestinal obstruction, Pregnancy
what is the MOA of Methylnaltrexone
Peripherally acting antagonist of mu
Reduces effects of opioids peripherally- Not centrally
what do you need to do if CrCl <30 for Methylnaltrexone
renal dose adj
does Methylnaltrexone cross the BBB?
No
who gets constipation
Diabetics, pregnant, opiate users
how do you treat diabetic related constipation?
Sugar-free products (Metamucil)
how do you treat pregnancy constipation?
bulk formers or emolients
what is contrind for preg constipation
mineral oil, castor oil, and osmotics
how do you treat opiate related constipation
exersice, adequate fluid, fiber, methylnaltrexone
what is best to use in elderly with constipation
Bulk-forming laxatives, enemas, glycerin, lactulose (especially good for bed-ridden patients)
“P” juices (peach, pear, prune)
what is best to avoid in elderly with constipation
Best to avoid saline laxative due to potential changes in electrolytes
how do you treat kids with constipation
“P” juices (peach, pear, prune)
<5yrs: glycerin suppositories, malt soup extract (mix with juice or breast milk), dark corn syrup, MOM, bisacodyl
Senna or mineral oil
what should you avoid using in kids with constipation?
stimulants and excessive use of enemas
why do kids get constipated?
diet and habits
how many days is considered acute diarrhea? Chronic
14 days is chronic
when should try not to use antimotility agents for diarrhea? why>
NO ANTIMOTILITY AGENTS IN DYSENTERY OR IF C.Diff IS POSSIBLE
Diarrhea is usually a healthy response
what does rotavirus cause?
Watery diarrhea lasting 3-7 days, 1/3 have fever
what are the 4 types of diarrhea?
secretory, osmotic, exudative, altered intestinal transit
what is secretory diarrhea? Does fasting help? whats the characteristic of stool?
excess H2O and electrolytes
NO
Clinically recognized by large stool volume > 1L/day with normal ionic contents/osmolality
what is osmotic diarrhea?
does fasting help?
substances that draw intestinal fluids
Poorly absorbed substances lead to retention of intestinal fluids = diarrhea
Clinically recognized if diarrhea stops when patient does not eat
what is exudative diarrhea?
d/t inflammatory disease of GI that discharge mucus, serum proteins, and blood into gut
3 alterations of the transit of colon
Reduced contact time in small intestine
Premature emptying colon
Bacterial Overgrowth
what causes reduced contact time in sm int
Intestinal Resection or Bypass Surgery
what causes premature emptying of the colon?
Metoclopramide
Erythromycin
what can lead to bacterial overgrowth in the colon?
Increased time of exposure can lead to bacterial overgrowth
drugs that induce diarrhea? lots…
Laxatives Antacids containing Mg Antineoplastics Colchicine NSAIDs Orlistat Antibiotics: Clindamycin, Broad spectrum ABX Antihypertensives- ACEI, Cardiac Agents-digoxin Cholinergics PPIs-esomeprazole H2-Blockers-famotidine
how does diarrhea present?
N/V, abdominal pain, HA, fever, chills, malaise
Weight Loss
Dehydration
4 ways to treat diarrhea nonpharmacologically
Discontinue consumption of solids and dairy for 24 hours (osmotic)
With N/V: mild low residue diet, as BM decrease begin bland diet
Rehydrate: Oral Rehydration Solutions, LR, D5W, NS
Maintain electrolytes
4 examples of antimotility agents
Diphenoxylate
Loperamide
Paregoric
Difenoxin
3 examples of absorbents used in diarrhea
Kaolin-pectin mix
Polycarbophil
Attapulgite
example of antisecretory used in diarrhea?
Bismuth susalicylate
anticholinergic used in diarrhea
atropine
what is a bacterial replacement used in diarrhea
Lactobacillus
enzymes used in treatment of diarrhea
lactase
antibiotics to treat diarrhea
metronidazole and vancomycin
what is the MOA of antimotility drugs in diarrhea?
Slow intestinal transit
Prolong contact and absorption
Increase gut capacity
what can antimotility agents do if diarrhea is infectious?
Make it worse
what is lomotil?
diphenoxylate
what is the onset of lomotil and when should you change if not working?
Clinical benefit usually within 48 hours
If no benefit within 10 days, change therapy
what is the contraindications for lomotil?2
Cdiff or entertoxin-producing bacteria
what is the MOA of loperamide?
Acts directly on intestinal muscles to inhibit peristalsis, prolonging transit time
what is the onset of loperamide?
w/in 48 hrs
what are the contraind of loperamide? 4
Patients w/a fever exceeding 101 F (38.3C)
Acute ulcerative colitis
Antibiotic associative colitis
Children under
what is the MOA of absorbents?
absorb nutrients, toxins, drugs, and digestive juices
what is Cholestryamine (questran)
An absorbent for bile salts and C.diff
what is the MOA of pepto-bismol
Stimulates Absorption of Fluid and Electrolytes Across the Intestinal Wall
Antisecretory, anti-inflammatory, and antibacterial effects
what can pepto-bismol cause in kids under 12
reye’s syndrome
what are the ADRs of pepto-bismol - 3
Blackened stools and tongue
Salicylism
Can induce gout attacks in susceptible patients
what are the drug int with pepto-bismol? 3
Anticoagulants and tetracycline; May interfere with radiologic studies
what is the onset of pepto-bis
<48 hrs
what is octreotide (sandostatin)
an antisecretory for diarrhea
what is the moa of octreotide (sandostatin)
Blocks the release of serotonin, Direct inhibitory effects
Reduces motility and facilitates water absorption from the gut
what is the official indication of octreotide (sandostatin)
control symptoms in pts with metastic vasoactive intestinal peptide-secreting tumor associated diarrhea
what is the offlabel use of octreotide (sandostatin)
Treatment of refractory diarrhea
what is the onset of octreotide (sandostatin)
1-3 days up to a week
what are the 2 adr’s of octreotide (sandostatin)
bradycardia, hyperglyc
what is the MOA of atropine in diarrhea
blocks vagal tone and prolongs gut transit time
what is ADR of atropine
anticholinergic
contraindications of atropine
Glaucoma, prostatic hypertrophy
what is the MOA of lactobacillus
Restores normal flora and intestinal function
what is the contraindication for lactobacillus
immuno-compromised pts
what is the lactase enzyme used for?
lactose intolerance
what is Zn used for in diarrhea?
adjunct to ORS
Reduction of stool output
Reduction of diarrhea duration
what is the proposed MOA of Zn
possibly action on intestinal ion transport
what is travelers diarrhea typically?
4-5 loose/watery stools per day with cramping, +/- fever, lasting 3-4 days without treatment
>80% bacterial
>90% occur in 1st two weeks of travel
what are risks associated with travelers diarrhea?
Ingestion of contaminated food or drink
meals eaten at home<restaurants
Age: small children and 21-29 yr olds
Type of infection correlated with destination, season, type of travel
what foods are at risk and may cause traveler’s diarrhea?
undercooked veggies, unpeeled fruit, raw/undercooked meat
3 prophylaxis for traveler’s diarrhea?
Dietary counseling
Bismuth subsalicylate (PeptoBismol)
Antibiotics
-Effective but irresponsible prophylaxis
what is problem with prophyl and abx
-Gives false sense of security
Resistance huge problem
Cipro 500mg daily is 95% effective in some areas
Campylobacter in Thailand 84% resistance within 4 year
if someone traveled to thialand and got diarrhea what might they have been infected with?
campylobacter
how do we treat travelers diarrhea - 2
Rehydration is key
Antibiotics
Cipro 500mg BID X 3 days
Azithromycin 1gm X1 or 500mg daily x 3 days
who gets C.Diff
Hospitalized or recently on abx
how do we treat c.diff?
metronidazole and vanco
