GI Medications Flashcards
(31 cards)
1
Q
Prototype PPI: omeprazole (Prilosec)
General information
A
- How to take PPI- activated by food intake, so should take 20-30 minutes before the first major daily meal. This way peak serum drug levels coincide when PPI activated
- PPI half life short at 1.5 hours, *yet continue to suppress acid for ~24 hours. They are able to do this as they are produced in a delay-released form
- Several days of PPT treatment needed before achieving maximal acid inhibition
- Long-term use: increased risk for osteoporotic fractures
- Precautions in patients with: pregnancy, lactating or have liver impairment
2
Q
Prototype PPI: omeprazole (Prilosec)
A
- Drug interactions:
- Coadministration of omeprazole and clarithomycin has been shown to increase plasma levels of both
- Potential to affect bioavailability of medications that depend on a lower pH for absorption
- Mineral deficiencies could occur with long-term use
- Decreased B2 absorption may occur
- Ginkgo and St. John’s wort may decrease plasma concentration
3
Q
Prototype PPI: omeprazole (Prilosec)
Side effects
A
Adverse effects include: headache, nausea, diarrhea, rash, and abdominal pain
•Serious adverse effects: blood disorders may occur, causing unusual fatigue and weakness
•Potential effects of taking long-term PPIs due to alteration in acidity:
•Increased risk for osteoporosis (due to interference with calcium absorption)
•increased risk of infection (due to changing the acidity of the stomach which is a natural barrier for bacterial infections); evidence suggests a possible link to developing pneumonia, clostridium difficile
4
Q
Prototype PPI: omeprazole (Prilosec)
Nursing responsibilities
A
- Nursing responsibilities
- Monitor liver function tests or ordered serum gastrin during prolonged drug use
- Monitor for vitamin B12 and folic acid malabsorption
- Teach the patient:
- Take 30 minutes before meals
- Eat foods with beneficial bacteria
- Sleep with a foam wedge or risers under the head of the bed frame
- Do not crush, break, or chew the tablets or capsules
- Avoid smoking, alcohol use, and foods that cause acid production and gastric discomfort
- Report GI bleeding, severe diarrhea, abdominal pain, nausea, vomiting, heartburn, pain with urination, or blood in urine to health care provider
5
Q
Prototype: ranitidine (Zantac)
General information
A
- Rapid absorption from small intestine
- 30-minute onset of action
- Not affected by food
- Half-life from 1 to 4 hours
- No known effects on the fetus
- Adverse effects if higher doses, renal disease (half the dose), or older adults:
- Confusion
- Restlessness
- Hallucinations
- Depression
6
Q
Prototype: ranitidine (Zantac)
Contraindications
Drug interactions
A
- Contraindication: NO antacids with H2 receptor antagonist, diminishes absorption
- Drug interactions:
- May decrease absorption of cefpodoxime, ketoconazole, and itraconazole
- Concurrent use can increase effects of alcohol, sulfonylureas, salicylates, and warfarin
- Antacids should not be given within 1 hour of H2-receptor antagonists
- Smoking decreases effectiveness
- Vitamin B12 deficiency may occur, and iron is better absorbed in an acidic environment
7
Q
Prototype: ranitidine (Zantac)
Side effects
And serious side effects
A
- Side effects: uncommon
- Serious adverse effects
- Blood dyscrasias neutropenia (decreased WBC) and thrombocytopenia (decreased platelets)
- Confusion may occur rarely, usually in elderly or with IV dosing
- With high doses - gynecomastia, impotence, or loss of libido in men
8
Q
Prototype: ranitidine (Zantac)
Nursing responsibilities
A
- Nursing responsibilities:
- Monitor gastric pain.
- Administer IV form of this medication slowly over several minutes to prevent bradycardia and hypotension
- Teach the patient taken with or immediately after meals.
- Share with the patient that antacids should be taken 2 hours before or after meals with a full glass of water
- Monitor kidney and kidney function
- Monitor elderly patients closely
- Inform the patient to take other prescription or nonprescription drugs, dietary supplements, or herbal products with approval of health care provider
- Nursing Responsibilities:
- Do not use OTC ranitidine for longer than 2 weeks
- Immediately report fever, excessive bruising, vomiting of blood, or black-colored stools to health care provider
- Teach the patient to avoid alcohol or smoking
- Instruct the patient to not breast-feed while taking it
- Tell the patient to immediately notify health care provider of any known or suspected pregnancy
- Low-dose OTC preparation is available
- Famotidine (Pepcid) is an alternative; it is the most potent H2 Receptor antagonist
9
Q
What are antacids?
A
- Antacids are alkaline substances that:
- Neutralize stomach acid to treat symptoms of heartburn
- Inactive pepsin
- Stimulates prostaglandin production in the mucosa and increase LES tone, which reduced gastric reflux
- Promote relief from heartburn; do NOT promote ulcer healing or eliminate H. pylori
- Do NOT coat the stomach
10
Q
How do antacids work?
A
- To work, the antacid needs to raise the gastric pH to at least 3.5
- *Frequently used in combination with other antiulcer drugs for symptomatic relief of heartburn due to PUD or GERD
- OTC medications safe if package directions followed
- Start working usually within 10-15 minutes; duration of action only 2 hours
- Rule of thumb:
- Antacids contain aluminum cause constipation
- Antacids that contain magnesium may cause diarrhea
11
Q
Types of antacids and possible disadvantages
A
- Types of antacids and possible disadvantages
- Bicarbonate
- Metabolic alkalosis (fatigue, mental status changes, twitching muscles, decreased RR)
- Gastric acid + bicarbonate causes bloating and belching
- Sodium
- Fluid retention; avoid if patient on a sodium restricted diet or if HTN, HF or renal impairment
- Magnesium
- Fatigue, hypotension, dysrhythmias (Sx of hypomagnesemia); diarrhea (laxative-effect)
- DO NOT TAKE IF YOU HAVE KIDNEY DISEASE
- Calcium
- Constipation, aggravated kidney stones, milk-alkali syndrome; renal failure may occur at high doses
- Carbonate antacids with milk or vitamin D can cause milk-alkali syndrome (HA, urinary frequency, anorexia, nausea, fatigue, permanent renal damage)
12
Q
Antacids
Drug interactions
A
- Drug interactions:
- Antacids increase stomach pH; so they affect the solubility and absorption of oral medications
- Acidic drugs may be less therapeutic; examples are NSAIDs, sulfonylureas, salicylates, warfarin, digoxin
- Basic drugs may have a greater effect; examples are morphine, antihistamines, TCA, amphetamines
- Enteric coated or delayed release drugs dissolve when reach more alkaline environment; earlier release may aggravate stomach lining and cause symptoms of N&V
- Form complexes with tetracyclines, prevents antibiotic from working; interferes with digoxin to
- Alters urine pH and increases excretion of acidic drugs and inhibits basic drug excretion like amphetamines
13
Q
Antacids
Nursing responsibilities or patient teaching
A
- Nursing responsibilities or patient teaching:
- Antacids are for occasional use only; seek medical attention if symptoms persist or recur
- Keep all scheduled laboratory visits
- Do not take antacids with magnesium if you have kidney disease
- Do not take antacids with sodium if you have heart failure or high blood pressure, or are on a sodium-restricted diet
- Take antacids at least 2 hours before other PO medications
- Report any increase in abdominal pain, diarrhea, or constipation
- Shake liquid preparations thoroughly before dispensing, and thoroughly chew antacid tablets until wet before swallowing
- Follow the label instructions carefully and keep within the recommended dosage range
14
Q
Miscellaneous Drugs to Treat PUD and GERD
Sucralfate
A
- Stimulates mucus, bicarbonate, and prostaglandin secretion that enhance mucosal defenses
- Acts locally and provides thick protective barrier that coats and binds to the ulcer preventing further erosion and a chance to heal.
- Effective in preventing NSAID ulcers
- May cause constipation
- Requires acid environment so do not take at same time as antacid, H2 receptor antagonist or PPI
- Needs to be taken four times daily
15
Q
Miscellaneous Drugs to Treat PUD and GERD
Simethicone
Bismuth
A
- Simethicone- antiflatulent, reduces gas
* Reduce bloating, discomfort or pain caused by excessive gas in the stomach or intestines
* Regular tablets, chewable tablets, capsules, and liquid to take by mouth
* Usually taken four times a day, after meals and at bedtime
* OTC examples- Maalox, Mylanta, Gas X - Bismuth subsalicylate (kaopectate, Pepto-Bismol):
* Stimulates mucosal bicarbonate and prostaglandin production and inhibits H. pylori by causing cell wall death to bacterium
* May be used to treat dyspepsia, heartburn and diarrhea
* SE: tinnitus, HA, N&V, dizziness
16
Q
Miscellaneous Drugs to Treat PUD and GERD
Metoclopramide (Reglan)
A
- Used for short-term (4-12 weeks) symptom management of GERD or PUD who fail to the other 1st line drugs
- Also treats for post-op or chemo-related N&V
- Route- PO, IM, IV
- MOA: faster emptying of stomach due to upper intestinal muscle contraction it causes
- SE: symptoms of Parkinsonism
17
Q
What is copnstipation?
A
- Constipation is a decrease in the frequency of bowel movements
- Diagnosis requires at least two symptoms:
- Two or fewer bowel movements per week
- Lumpy or hard stools at least 25% of time
- Straining to pass stools at least 25% of time
- Feeling of incomplete evacuation at least 25% of time
18
Q
What do laxatives do and what are the types?
A
- Laxatives are used to increase the frequency and quality of bowel movements; promote defecation; use to treat constipation
- Laxative types:
- Bulk-forming
- Stimulant
- Surfactant
- Osmotic
- Mineral oil
19
Q
Bulk - forming laxatives
A
- Bulk-forming laxatives:
- MOA: absorb water, adding to size of fecal mass
- Agents of choice taken to treat and prevent chronic constipation
- Onset of action: 24-48 hours
- SE: psyllium muciloid (Metamucil) if taken with insufficient water may swelling esophagus and cause obstruction
- Contraindications: undiagnosed abdominal pain, intestinal obstruction
- Drug interactions: warfarin, digoxin, antibiotics and salicylates
- Overdose: unlikely
- Patient teaching: contains sugar and sodium; may contain artificial sweeteners which is a problem for patients with PKU; do NOT breast feed
20
Q
Stimulant laxatives
A
- Stimulant laxatives:
- Promote peristalsis by irritating the bowel
- Rapid acting and Not be used routinely
- Indicated for “bowel pre” prior to bowel exams or surgeries
- Rapid acting; onset of action 6-12 hours PO or 1-6 hours rectally
- SE:
- Diarrhea and cramping, electrolyte imbalances; may alter vitamin K absorption so monitor patient closely if concomitantly taking anticoagulants
- Example: bisacodyl (Dulcolax)
- Example: Castor oil (Emulsoil, Neoloid)
- One of oldest and worst-tasting laxatives approved by FDA
21
Q
Surfactants laxatives
A
- Surfactant:
- Commonly called stool softeners
- MOA: cause more water and fat to be absorbed into the stools
- Onset of action 24-48 hours
- Do NOT treat constipation, rather it helps prevent it
- Indicated for patients with recent surgery or when the patient should not strain such as after a MI or delivering a baby
- SE:
- mild abdominal cramping, diarrhea, bitter taste
- Drug interactions:
- Do not take with mineral oil; increased absorption
- Example: docusate or Colace
22
Q
Osmotic laxatives or saline cathartic
A
- Osmotic laxative or saline cathartics:
- Increase fecal water content
- Examples- GoLYTELY, sorbitol, glycerin, lactulose
- Frequently used as bowel prep before surgery
- Saline- increases water & electrolyte secretion, watery stool distends.
- Examples- enemas
- Onset of action: 1-6 hours
- SE:
- patients with diarrhea for F&E imbalances
- Teach the patient that overuse leads to laxative dependency
23
Q
Mineral oil “lubricant laxatives”
A
Mineral oil “lubricant laxatives”:
•Lubricates & prevents reabsorption, water softens & distends bowel
•Should be discouraged as it interferes with absorption of fat-soluble vitamins
•Onset of action: 24-48 hours
•SE: diarrhea, nausea
•Example: lubiprostone indicated for the constipation form of irritable bowel syndrome
•Example:methylnaltrexone- for patients with advanced illness experiencing constipation from opioid use
24
Q
Antiadarrheals
Anti cholinergic
Opioids
Probiotics
A
- Antidiarrheals:
- Adsorbants-coat the walls of the GI tract, bind the cause & eliminate through the stool
- e.g. bismuth subsalicylate (form of aspirin),Pepto Bismol, Kaopectate
- Anticholinergics- lomotil; slows peristalsis; anti-motility
- Opioids- slows peristalsis allowing for more fluid and electrolyte absorption in the large intestine; scheduled V drug; short-term use only
- Probiotics- lactobacillus a normal inhabitant of gut and vagina; sometimes taken to correct altered GI flora following a serious diarrheal episode
25
Drugs for nausea and vomiting
* Anti-emetics are prescribed to treat nausea and vomiting
* Treatments:
* Anticholinergic agents and antihistamines
* Phenothiazines - prototype
* Benzodiazepines
* Cannabinoids
* Corticosteroids
* Serotonin (5-HT3) receptor antagonists
26
Nausea and vomiting
Anti cholinergic agents and antihistamines
Benzodiazepines
Cannabinoids
Anticholinergic agents and antihistamines:
•Agents for treating simple nausea due to motion sickness (disorder of the inner ear)
•Examples- scopolamine (Trans-der Scop), Dramamine
•Take drug 20-60 minutes before travel
•Benzodiazepines:
•Treat anxiety associated with chemotherapy anticipation of severe nausea and vomiting
•Not monotherapy for antiemetic
•Cannabinoids:
•Contain same drug as marijuana produces antiemetic effect and relaxation, but not the euphoria associated with marijuana
27
Nausea and vomiting
| Phenothiazines
* Phenothiazines (dopamine antagonists):
* Usually treated for psychoses, yet also effective antiemetic
* Inhibits dopamine receptors and the severe nausea associated with antineoplastic treatments
* Stimulates peristalsis in the GI tract, emptying stomach
* SE: sedation, extra-pyramidal symptoms
* Older example- promethazine (Phenergan) P), rectal and parenteral; metoclopramide (Reglan), prochlorperazine (Compazine)
28
Phenothiazine Prototype: Compazine
| Drug interactions
* Use with tricyclic antidepressants, antihistamines, and other agents with anticholinergic activity may produce increased anticholinergic and hypotensive adverse effects
* Concurrent use with SSRIs will slow metabolism of phenothiazine and raise serum concentrations
* Interacts with alcohol and other CNS depressants to cause additive sedation and respiratory depression
* Antacids and antidiarrheals inhibit absorption
* When taken with phenobarbital, metabolism of prochlorperazine is increased
29
Phenothiazine Prototype: Compazine
| Nursing responsibilities
* Place nauseated patients with altered consciousness in a side-lying position to prevent aspiration of vomitus
* Withhold foods and fluid until nausea subsides
* Do not drive or perform other hazardous activities until effects of drug are known
* Avoid alcohol
* Do not take if tardive dyskinesia has previously occurred when taking other medications
30
Nausea and vomiting
Corticoids
Serotonin receptor antagonists
* Place nauseated patients with altered consciousness in a side-lying position to prevent aspiration of vomitus
* Withhold foods and fluid until nausea subsides
* Do not drive or perform other hazardous activities until effects of drug are known
* Avoid alcohol
* Do not take if tardive dyskinesia has previously occurred when taking other medications
31
Nausea and vomiting
| Nursing responsibilities/teaching for anti - emetics
* Nursing responsibilities/teaching for anti-emetics:
* Monitor F&E status, I&O, skin turgor, VS
* Most cause drowsiness
* Some cause hypotension
* Avoid alcohol & CNS depressants
* Scopolamine patches, behind ear, rotate sites, wash hands after handling
