Exam 2: GI disorders Flashcards Preview

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Flashcards in Exam 2: GI disorders Deck (55):

What are Antacids and what is their action?

- Weak bases that interact with stomach acid to form water and salt
- They act locally to treat excess acidity and raise gastric pH.


At what pH is pepsin maximally active?

- pH = 2
- When pH > 4, pepsin activity decreases


At what pH do best antacids buffer to?

pH of 3-4


Do Antacids inhibit HCl production by parietal cells?

- No
- Need HCl for digestion


Side effect of Antacids?



Name the 3 primary compounds used alone or in combination in antacid products

1. Aluminum salts
2. Magnesium salts
3. Calcium carbonate


Which of the primary compounds used in antacids are poorly absorbed?

Calcium and Magnesium


Which of the primary compounds used in antacids are not absorbed at all?



Which of the primary compounds in antacids form compounds in the small intestines that may lead to constipation?

Calcium carbonate


How does Milk of Magnesia work?

Hydroxide ions bind with HCl in stomach = neutralizes


How does Maalox work and what is its onset of action time?

- Coats ulcerated area and protects ulcers from HCl
- Reacts with gastric acid to form silicon dioxide in stomach (silica absorbs H+)
- Neutralizes gastric pH
- Slow acting


Explain the action of Amphojel

- Aluminum is astringent to stop bleeding
- Coats and protects ulcers from H+
- Interferes with absorption of tetracyclines


How much milk can neutralize one volume of acid?

One volume of milk


Describe the action of sucralfate (Carafate)

- Forms complexes with albumin, fibrinogen and globulin on ulcer surface, thus creating protective barrier to acid and pepsin
- Interfers with the absorption of many medications
**Not absorbed


When is Sucralfate indicated?

First choice therapy in the management of acid-related diseases during pregnancy


Name the Histamine H2 Receptor Antagonists used for acid control?

- Tagamet
- Pepcid
- Axid
- Zantac


Which of the Histamine H2 Receptor Antagonists are preferred by gastroenterologists?



What is Tritec and when is it indicated?

- It is a prescription with antibiotics (clarithromycin) that is used to treat ulcers
Histamine H2 Receptor Antagonist


How do Proton Pump Inhibitors work?

- Bind to H+/K+-ATPase (Proton pump) enzyme system in parietal cells
- This is the final common pathway for acid secretion.


What are the effects of Proton Pump Inhibitors on acid secretion?

1. Reduces gastric secretions
2. Neutralize gastric acid after release
3. Protect gastric mucosa from damage


Which have better nocturnal acid control, Proton Pump Inhibitors or Histamine H2 Receptor Antagonists?

- Histamine H2 Receptor Antagonists have nocturnal acid control
- PPI's have poor nocturnal acid control


Name the 5 available Proton Pump Inhibitors

1. Nexium
2. Prevacid
3. Prilosec
4. Protonix
5. Aciphex


Which of the Proton Pump Inhibitors are sold over the counter?



What are the indications for Nexium?

- Indicated for use for prevention and treatment of NSAID-induced gastrointestinal lesions
- Better at healing erosive lesions than Prilosec


5 Dental Treatment Planning Considerations

1. Drug interactions with antacids
2. Histamine antagonists decrease antifungals
3. Histamine antagonists alter warfarin
4. Tagamet = increases serum concentration
5. PPI's decrease absorption of systemic antifungals


Define in more detail what occurs with drug interactions and antacids

1. Binding of drugs in stomach = metals
2. Antacids neutralize pH = interferes with absorption of many drugs = wait 2 hours
3. Interferes with bioavailability and elimination of many drugs


Oral complications of GI medications

- Xerostomia
- Taste alteration (metallic)
- Aphthous stomatitis
- Candidiasis (esophageal)
- Excessive salivation


Peak prevalence of peptic ulcer disease (age)

- Young adulthood (30 years to 50 years of age)
- First degree relatives threefold higher risk


There is a higher prevalence of peptic ulcer disease in what patients?

1. Smokers
2. Heavy Drinkers
3. Hyperparathyroidism
4. Renal dialysis patients
5. Use of NSAIDS (chronic use)


Death from peptic ulcer disease is more likely in what age group?



What is the etiology of peptic ulcer disease?

- Helicobacter pylori infection
- *Humans are only known hosts of H. pylori
- *Organism resides in oral cavity
Present in 90% of cases


Name the contributing factors to peptic ulcer disease

1. Acid hypersecretion
2. Smoking
3. Stress = increases acid secretion
4. Use of NSAIDS for > 1 month


Name 3 complications of peptic ulcer disease

1. H Pylori associated with cancer of gastric mucosa = lymphoma
2. Peptic ulcers rarely undergo transformation to carcinoma
3. Atrophic gastritis caused by chronic use of proton pump inhibitors increases risk for stomach cancer


Treatment of peptic ulcer disease if it is an uncomplicated ulcer:

Antisecretory drugs


Treatment of peptic ulcer disease if H. pylori is present

Antisecretory drugs + antibiotics


What combination therapy can be used to treat peptic ulcer disease with H. pylori present?

Antibiotics + proton-pump inhibitor or Pepto Bismol


Antibiotics are used in combination with what other two acid drugs to treat ulcers caused by H. pylori

1. Proton pump inhibitors
2. H2 receptor blockers


What antiboitics are used to treat H. pylori?

1. Amoxicillin
2. Metronidazole
3. Clarithromycin
4. tetracycline


What is the normal procedure once H. pylori is detected in patients with a peptic ulcer?

- Eradicate it and allow the ulcer to heal
- Standard first-line therapy is a one week triple therapy consisting of the antibiotics:
○ Amoxicillin
○ Clarithromycin


What is used to treat clarithromycin-resistant strains of H. pylori?

Levofloxacin (Levaquin) is added as part of the therapy


What drugs should be avoided when a patient has peptic ulcer disease?

- Avoid aspirin, NSAIDS
**Use acetaminophen or COX-2 inhibitor


Name the oral manifestations of peptic ulcer disease

- Vascular malformations of lip
- Enamel erosion


Name the 2 dental treatment planning considerations for a patient with Peptic Ulcer disease

1. Macrolide antibiotics (erythromycin) cause GI distres and diarrhea
a. Caution in patients with IBS
b. Antibiotics: macrolides, cephalosporins, clindamycin = pseudomembraneous colitis
2. Avoid aspirin/NSAIDS in patients with Hx of stomach ulcers


Name the two distinct conditions of IBS

1. Ulcerative Colitis
2. Crohn's disease


Etiology of IBS:

- Unknown
○ Allergy
○ Destructive enzymes
○ Bacterial and viral infections
○ Stress
○ Immunologic factors
- Atypical mycobacteria in minority of Crohn's patients


Name the 3 lines of treatment of IBS

1. Anti-inflammatories; corticosteroids
2. Immunosuppressive agents; Antibiotics
3. Monoclonal antibody; Surgical resection
**Supportive Therapy = rest, dietary changes, nutritional supplementation


3 drugs to have caution with in a patient with IBS

1. Use of Corticosteroids
a. Risk for adrenal suppression
2. Immunosuppressive drugs
a. Blood dyscrasias = order blood tests
b. Damage liver = order liver function test
3. Caution with analgesics
a. Avoid aspirin and NSAIDS


T or F, in patients with acute episodes of IBS, it is ok to perform elective dental procedures as well as urgent, emergency dental procedures

- False, only urgent, emgerceny dental care during acute episodes
Elective procedures done during remission


Name the oral manifestations of Crohn's

- Atypical mucosal ulcerations, diffuse swelling of lips and cheeks, cobblestone mucosal lesions
- Aphthous ulcerations


Name the 3 Antidiarrheal agents

1. Absorbents
2. Opioids - paregoric
3. Ioperamide (Imodium)


Describe the absorbent antidiarrheal agents

- Bismuth subsalicylate (pepto-bismol)
- Caution with salicylate allergy


Describe the opioids - paregoric antidiarrheal agents

- Codeine and diphenoxylate (in Lomotil) = prescription drug
- Remember that codeine causes constipation as a side effect.


What is Imodium?

- Muscle relaxant
- Relieves spasm and decreases gut motility


Patient considerations with laxatives

- Inactivity
- Inadequte water intake
- Motility problems
- Medication-induced constipation
- Dependency upon these products
- Eat more fiber-containing foods


Name the 4 types of laxatives

1. Bulk - Carboxymethyl cellulose with psyllium
a. Absorb water to form softened stools by increasing bulk of intestinal contents
2. Osmotic - magnesium salts (OTC)
a. Used as prep for colonoscopy
3. Contact - bisacodyl
a. Bisacodyl also used in high doses as colonoscopy prep
4. Lubricants - mineral oil, glycerin
a. Act as emollients