Gastrointestinal Pharmacology Quiz

Drugs Affecting the Digestive and Endocrine Systems

• Digestive System Overview: The digestive system breaks down food, absorbs nutrients, and eliminates waste. Organs involved include the mouth, pharynx, esophagus, stomach, liver, gallbladder, small intestine, large intestine, and rectum/anus. Different enzymes and hormones aid in these processes.

Learning Objectives

• Students should understand gastric ulcers and GERD (Gastroesophageal Reflux Disease).
• Students should describe the mechanism of action of drugs for gastric ulcers and GERD.
• Students should describe the mechanism of action of different types of laxatives.

Natural Defenses Against Stomach Acid

• Stomach lining has a bicarbonate barrier to neutralize acid.
• Mucus layer protects stomach lining from gastric juice (pH ~2).
• Gastric mucosa cells and capillaries are also involved in the protection process.

Peptic Ulcer Formation

• Normal: Damaging factors (gastric acidity, peptic enzymes), protective factors (mucus, bicarbonate secretion, etc.) balance.
• Injury: Stressors such as H. pylori infection, NSAIDs, alcohol, gastric hyperacidity or reflux upset the balance, increasing damage.
• Ulcer: Tissue damage occurs when injurious factors exceed or impair protective factors, leading to ulcers.

Functions of Stomach Acid

• Creating an acidic environment to inactivate pathogens.
• Protect against infections.
• Aid in protein digestion through activation of pepsin.

Gastric Acid Formation

• Parietal cells are responsible for stomach acid production.
• Histamine and other factors play a role in stimulating the proton pump, which transports acid into the stomach.

Gastric Ulcers

• Characterized by gnawing or burning pain in the upper abdomen.
• Progression can lead to bleeding and perforation if the erosion gets deeper.
• Helicobacter pylori (H. pylori), a bacteria, is a common cause of stomach ulcers.

Gastroesophageal Reflux Disease (GERD)

• A condition where stomach acid moves upwards into the esophagus.
• Causes intense heartburn and may lead to esophageal ulcers.
• Stomach sphincter plays a role in preventing reflux.

Drug Therapy

• Proton pump inhibitors (PPIs): Potent acid inhibitors that reduce stomach acid by irreversibly binding to the acid producing enzyme (H+, K+, ATPase).
• H2 receptor blockers: Reduce acid production by blocking H2 receptors.
• Antacids: Rapidly neutralize stomach acid using compounds of aluminum, magnesium, or calcium.
• Antibiotics: Used to eliminate H. pylori to treat infection-related ulcers and other problems.

Specific Drug Discussion (PPIs)

• Mechanism of Action: Block H+, K+, ATPase enzyme, reducing stomach acid secretion.
• Use: Treating peptic ulcer disease, GERD, H. pylori infection.
• Drugs: Omeprazole, Lansoprazole, etc.

Specific Drug Discussion (H2 Receptor Blockers)

• Mechanism of Action: Block H2 receptors to lower acid production.
• Use: Ulcers, GERD
• Drugs: Famotidine, Ranitidine

Specific Drug Discussion (Antacids)

• Mechanism of Action: Neutralize stomach acid.
• Use: Reduce symptoms of peptic ulcers ,GERD
• Drugs: Aluminum Hydroxide and Magnesium Hydroxide combinations (e.g. Triact

Specific Drug Discussion (Antibiotics)

• Mechanism of Action: Eliminate H. pylori infection, which causes ulcers.
• Use: Use in combination with other drugs to treat ulcers..
• Drugs: Amoxicillin, Clarithromycin, and Metronidazole, Tetracycline.

H.pylori Eradication Therapies

• Triple therapy: PPI, Clarithromycin, Amoxicillin (14 days).
• Quadruple therapy: PPI, Bismuth, Tetracycline, Metronidazole (14 days).
• Sequential therapy: combination regimens (variable time periods for each).

Constipation

• Characterized by infrequent bowel movements, difficult stool passage, and persists for several weeks or longer.
• When stool moves too slowly through the digestive tract.

Laxatives

• Bulk-forming: Absorb water, increasing fecal mass and stimulating bowel activity.
• Osmotic: Increase osmotic pressure in the colon, drawing water into the stool and softening it.
• Stool softeners/Surfactants: Reduce surface tension of stool to allow penetration of water inside stool for better pass.
• Stimulants: Irritate the bowel, stimulating bowel muscle contractions

Nursing Considerations for Drugs

• PPIs: Take 15-30 minutes before food, do not chew.
• H2 Receptor Blockers: Take with food.
• Antacids: Can be chewed, taken with or after food.
• All drugs: Administer separate from other medications to avoid interactions.

Lifestyle Changes for GERD

• Quit smoking
• Eat small meals often;
• Chew food slowly
• Avoid heartburn triggers (caffeine, alcohol, etc)
• Maintain good posture - sitting up straight; no lying down after meals.
• Sleep with elevation of your head and shoulders.

Endocrine System Overview

• The endocrine system is a network of glands that regulate the body's functions using hormones.
• The endocrine glands produce and secrete hormones that control various bodily processes.

Learning Objectives for Endocrine System

• Students should understand feedback mechanisms in endocrine systems.
• Students should describe the mechanism of action of drugs for diabetes mellitus.

Hormones: Role in Homeostasis

• Chemical messengers for communication in the body.
• Feedback mechanisms: Positive feedback amplifies responses, while negative feedback opposes them.

Hormones Associated with Hypothalamus and Pituitary

• Releasing and inhibiting hormones regulate the release of other hormones.
• Hypothalamus and pituitary gland regulate various bodily functions.

Hormone Replacement Therapy

• Hormones are administered to compensate for insufficient endogenous hormones.
• Use in cancer treatment therapies to shrink size of hormone-sensitive tumors.
• Example: Tamoxifen for breast cancer treatment.

Thyroid Gland

• Regulates the basal metabolic rate.
• Produces hormones (T3, T4) which control many bodily functions, including metabolism.
• The Hypothalamus and Pituitary gland regulate thyroid function through negative feedback.

Hypothyroidism

• Insufficient thyroid hormone production.
• Symptoms include: weakness, muscle cramps, weight gain, slow metabolism, cold intolerance.
• Treated with Levothyroxine (synthetic thyroid hormone).

Hyperthyroidism

• Excess thyroid hormone production.
• Symptoms include: goiter, nervousness, tremors, weight loss, heat intolerance.
• Treated with anti-thyroid drugs, surgery, or radioactive iodine.

Diabetes Mellitus

• A metabolic disorder characterized by high blood glucose levels.
• Types: Type 1 (insulin deficiency) and Type 2 (insulin resistance).

Diabetes Mellitus Signs and Symptoms

• High fasting blood sugar (2 readings)
• Polyuria (frequent urination)
• Polyphagia (increased hunger)
• Polydipsia (increased thirst)
• Glycosuria (glucose in urine)
• Weight loss
• Fatigue

Diabetic Drugs (Oral and Parenteral Hypoglycemics)

• Sulfonylureas: Increase insulin secretion from beta cells.
• Biguanides: Reduce glucose production, increase its uptake.
• Alpha-glucosidase inhibitors: Slow carbohydrate digestion.
• Dipeptidyl peptidase-4 (DPP-4) inhibitors: Increase incretin activity, potentially lowering blood glucose.

Insulin

• Naturally produced hormone for blood sugar control.
• Types: Rapid-acting, short-acting, intermediate-acting, long-acting and combinations.
• Delivery method: injections.

Nursing Considerations for Drug Therapies

• Insulin: Monitor blood glucose levels, give before meals, keep carbs available, rotate injection sites.
• Sulfonylureas: Monitor blood glucose levels, give 15 minutes before meals.
• Biguanides: Administer with meals; monitor glucose levels carefully; avoid in kidney patients.
• Alpha-glucosidase inhibitors: Administer at the start of a meal, monitor glucose levels.

General Notes

• Always check with a medical professional for specific instructions regarding drug use.
• Lifestyle modifications (diet, exercise) are crucial for managing diabetes, in addition to prescription drugs.
• Be sure to follow healthcare providers' instructions carefully.

Test your knowledge on gastrointestinal pharmacology and the treatment of issues like gastric ulcers and GERD. This quiz covers drug mechanisms, Helicobacter pylori treatment, and the effects of various gastrointestinal medications. Expand your understanding of how these treatments function within the digestive system.