NURS 1102 – Applied Pharmacology Classification: General Exam 3 Review

Module 11: Endocrine Agents

  • Thyroid Replacement Therapy

    • Thyroid replacement therapy is primarily used to treat hypothyroidism. It functions by replacing missing thyroid hormones (Thyroxine/T4 or Triiodothyronine/T3), thereby restoring normal metabolic rate, body temperature, and growth/development in patients with deficient thyroid function.

    • Side Effects of Thyroid Agents (e.g., Levothyroxine): Most side effects result from excessive dosage (hyperthyroidism). These include tachycardia, palpitations, cardiac arrhythmias, nervousness, insomnia, irritability, weight loss, heat intolerance, and tremors.

    • Thyroid Storm: This is a life-threatening health condition associated with untreated or undertreated hyperthyroidism. Symptoms include a high fever, extreme palpitations (tachycardia), vomiting, diarrhea, and severe agitation or mental confusion.

    • Hyperthyroidism Treatment: Medications include thioamides such as Propylthiouracil (PTUPTU) and Methimazole. Other treatments include radioactive iodine therapy to destroy thyroid tissue or surgical removal of the gland.

  • Glucocorticoids

    • Therapeutic Uses: Glucocorticoids are used to manage inflammation, suppress the immune system (e.g., after organ transplants), and treat autoimmune disorders, allergic reactions, and adrenal insufficiency.

    • Adverse Reactions and Side Effects: Risks include hyperglycemia, weight gain, fluid retention, hypertension, osteoporosis, peptic ulcers, muscle wasting, increased susceptibility to infection, and delayed wound healing.

    • Tapering and Adrenal Crisis: Patients must be tapered off glucocorticoids slowly because the administration of exogenous steroids suppresses the body's natural production of cortisol via the hypothalamic-pituitary-adrenal (HPAHPA) axis. Abrupt withdrawal can lead to an adrenal crisis, characterized by profound hypotension, dehydration, and electrolyte imbalances.

  • Mineralocorticoids

    • Main Mineralocorticoid: Aldosterone is the primary mineralocorticoid produced by the adrenal cortex. It works by promoting sodium and water retention and potassium excretion in the kidneys to maintain blood volume and pressure.

    • Clinical Syndromes:

      • Addison\'s Disease: Caused by too little corticosteroid production.

      • Cushing\'s Syndrome: Caused by excessive levels of corticosteroids, often due to exogenous medication or adrenal/pituitary tumors.

  • Corticosteroid Interactions

    • Antidiabetic Drugs: Corticosteroids can increase blood glucose levels, effectively antagonizing and decreasing the efficacy of antidiabetic medications (insulin and oral agents).

    • Blood Pressure: These drugs cause sodium and water retention, which typically leads to an increase in blood pressure.

  • Insulin Management

    • Classifications and Examples:

      1. Rapid-Acting: e.g., Lispro (Humalog), Aspart (Novolog).

      2. Short-Acting/Regular: e.g., Humulin R, Novolin R.

      3. Intermediate-Acting: e.g., NPH (Humulin N).

      4. Long-Acting: e.g., Glargine (Lantus), Detemir (Levemir).

    • Adverse Effects: The most common and dangerous adverse effect is hypoglycemia, which is most likely to occur at the peak action time of the insulin.

    • Mixing Insulin: Regular (Short-acting) insulin can be mixed with NPH (Intermediate-acting) insulin. The mnemonic \"Clear before Cloudy\" dictates that the regular (clear) insulin should be drawn into the syringe first.

    • Pharmacokinetics: Knowledge of onset, peak, and duration is critical to ensure that peak glucose-lowering effects coincide with food intake to maintain normoglycemia.

  • Diabetes Mellitus (DM)

    • Type I vs. Type II: Type I is an autoimmune destruction of beta cells leading to an absolute lack of insulin, requiring lifelong insulin therapy. Type II involves insulin resistance or relative insulin deficiency, often managed with oral antidiabetics (e.g., Metformin), lifestyle changes, and potentially insulin later in the disease progression.

    • Timing of Regular Insulin: Ideally, food should be ingested within 3030 minutes after administering regular insulin to avoid hypoglycemia.

    • Acute Illness Impact: Infections, trauma, or surgery increase metabolic stress and cortisol levels, which raises blood glucose. Patients who are normally stable may require temporary insulin during these episodes.

    • Diagnostic and Monitoring Tests: DM is diagnosed via Fasting Plasma Glucose (geq126 mg/dL\\geq 126\,mg/dL) or Hemoglobin A1CA1C (geq6.5%\\geq 6.5\%). Monitoring involves frequent capillary blood glucose checks and periodic A1CA1C tests to assess long-term control (average blood sugar over the past 33 months).

    • Hypoglycemia Signs: Nervousness, tremors, sweating, tachycardia, palpitations, hunger, confusion, and dizziness.

  • Reproductive Health

    • Oral Contraceptives: Side effects include nausea, breast tenderness, breakthrough bleeding, and risk of thromboembolic events. Contraindications include smoking (especially in women over 3535), a history of blood clots, or estrogen-dependent cancers.

    • Other Uses: Prescribed for cycle regulation, reduction of menstrual cramps (dysmenorrhea), and acne treatment.

    • Alternate Routes: Include the transdermal patch, vaginal ring, injectable depot shots (Depo-Provera), and intrauterine devices (IUDsIUDs).

    • Menopause: Characterized by hot flashes, night sweats, and vaginal dryness. Pharmacologic management often involves Hormone Replacement Therapy (HRTHRT) using estrogen (and progestin if the patient still has a uterus).

    • Impotence (ED) and BPH: Phosphodiesterase type 5 inhibitors (e.g., Sildenafil) are used for ED; patients must not take these with organic nitrates (e.g., nitroglycerin) due to severe hypotension risk. Benign Prostatic Hypertrophy (BPHBPH) is an enlargement of the prostate treated with Alpha-1 blockers or 5-alpha reductase inhibitors.

Module 12: Gastrointestinal Tract Agents

  • Acid Control

    • H2 Receptor Antagonists: Used to treat GERD and peptic ulcers by reducing gastric acid secretion. Patients should be taught to avoid smoking and substances that irritate the gastric mucosa.

    • Proton Pump Inhibitors (PPIs): These block the H+/K+H^+/K^+ ATPase enzyme system (the proton pump) in the stomach, providing more potent acid suppression than H2 blockers.

    • Peptic Ulcer Disease (PUD): Primarily caused by H. pylori bacteria or chronic use of NSAIDSNSAIDS. NSAIDSNSAIDS are contraindicated because they inhibit prostaglandins that protect the gastric lining.

  • Antiemetic Agents

    • Chemotherapy Support: Serotonin antagonists (e.g., Ondansetron/Zofran) are typically given before chemotherapy because they are highly effective at blocking the nausea signals triggered by cell-destroying drugs.

    • Drug Mechanisms:

      • Anticholinergics/Antihistamines: Block signals from the inner ear and vestibular tract; side effects include dry mouth, blurred vision, and drowsiness.

      • Dopamine Antagonists: Block dopamine receptors in the CTZ (chemoreceptor trigger zone); side effects include extrapyramidal symptoms (EPSEPS) and sedation.

  • Laxatives and Antidiarrheals

    • Antidiarrheals: Opiates (e.g., Loperamide or Diphenoxylate/Atropine) slow intestinal motility. Nurses assess effectiveness by monitoring stool frequency and consistency. Teaching includes increasing fluid intake to prevent dehydration.

    • Laxative Categories:

      • Bulk-forming: Fiber-based, safe for long-term use.

      • Stimulant: Irritate the bowel to stimulate peristalsis.

      • Osmotic: Pull water into the colon.

    • Absorption Issues: Laxatives and antacids can speed up transit or change pH, which may decrease the absorption of other medications.

    • Constipation Prevention: High-fiber diets, adequate hydration, and regular physical activity.

    • Adsorbents: Often used to prevent travel-related diarrhea or bind specific toxins.

Modules 13 & 14: Antibacterial and Antiviral Agents

  • General Concepts

    • Antiinfectives: A broad class of drugs that kill or inhibit organisms including bacteria, viruses, fungi, and parasites.

    • Microbiology Testing: A Culture and Sensitivity (C&SC\&S) test identifies the specific pathogen and which drugs it is susceptible to. It must be collected before starting antibiotics to ensure accuracy.

    • Antibiotic Guidelines: Patients must complete the full course to prevent bacterial resistance. Automatic stop dates are used (especially for strong meds) to prevent superinfections or toxicity.

  • Classification and Resistance

    • Bactericidal: Kills the bacteria directly.

    • Bacteriostatic: Inhibits the growth/reproduction of bacteria, allowing the immune system to finish the job.

    • Nosocomial Infection: An infection acquired within a healthcare setting (hospital-acquired).

    • Opportunistic Infection: Occurs when the body\'s normal flora is disturbed, allowing usually harmless organisms to cause illness.

    • Superinfection: A new infection that appears during the treatment of a primary infection (e.g., C. diff or oral thrush).

  • Specific Antibiotic Risks

    • Penicillin Allergy: Patients allergic to penicillin may have a cross-sensitivity to cephalosporins (e.g., Cephalexin, Cefazolin). They must avoid all penicillin derivatives (Amoxicillin, Ampicillin).

    • Aminoglycosides (e.g., Gentamicin): Major side effects include ototoxicity (hearing loss/vertigo) and nephrotoxicity (kidney damage). Monitoring through peak and trough levels is essential.

    • Macrolides (e.g., Erythromycin): Inhibit protein synthesis and serve as a safe alternative for patients allergic to penicillin.

    • Tuberculosis Treatment: Usually involves a multi-drug regimen (e.g., RifampinRifampin, IsoniazidIsoniazid) taken for 66 to 1212 months to prevent the development of resistant strains.

  • Viruses and Fungi

    • Meningitis: Viral meningitis is usually self-limiting and managed with supportive care, whereas bacterial meningitis involves intensive antibiotic treatment.

    • Herpesviruses: Treated with antivirals like Acyclovir, which inhibit viral DNADNA replication.

    • Antifungals: Work by disrupting the fungal cell membrane; common pathogens include Candida albicans (yeast) and Tinea (ringworm). Fungi are eukaryotic and have more complex structures than the simpler prokaryotic bacteria.

  • Immunizations

    • Active Immunity: The body produces its own antibodies in response to an antigen (vaccine or illness).

    • Passive Immunity: Antibodies are transferred from another source (e.g., breast milk or immune globulin) providing temporary protection.

    • Travel Vaccines: Required due to endemic diseases in specific geographic regions that the traveler\'s immune system hasn\'t encountered.

Module 15: MSK, Eye, Ear, and Skin Agents

  • Bone and Joint Health

    • Hypocalcemia: Causes include Vitamin D deficiency, hypoparathyroidism, or high phosphate levels.

    • Osteoporosis: Characterized by low bone density. Risk factors include aging, female gender, smoking, and long-term steroid use.

    • Bisphosphonates: Act by inhibiting bone resorption. Patient teaching includes taking the drug with a full glass of water first thing in the morning and remaining upright for at least 3030 minutes to prevent esophageal erosions.

    • Arthritis: Osteoarthritis is degenerative (wear and tear); Rheumatoid Arthritis is an autoimmune inflammatory condition. DMARDsDMARDs (Disease-Modifying Antirheumatic Drugs) are used for RA to slow joint destruction.

    • Gout: A build-up of uric acid crystals in joints. Colchicine is used for acute attacks; Allopurinol is used for chronic management. Avoid high-purine foods (organ meats, red meats, alcohol).

  • Eye and Skin

    • Glaucoma: Treated with Cholinergic agonists (increase outflow) or Prostaglandins. Beta-adrenergic blockers (e.g., Timolol) can cause systemic bradycardia or bronchospasm if systemic absorption occurs; patients should be taught to apply pressure to the lacrimal duct for 11 minute after administration.

    • Acne Vulgaris: Treated with topical agents (benzoyl peroxide), antibiotics, or retinoids like Isotretinoin (which requires strict pregnancy prevention).

Module 16: Contrast Agents

  • General Use

    • Main types are Iodinated (highest allergy risk), Barium (for GI studies), and Gadolinium (for MRIMRI). These agents enhance visualization of internal structures during diagnostic imaging (CTCT, X−rayX-ray, etc.).

    • Extravasation: Leakage of contrast into the tissue around an IV site. Nurses assess for pain, edema, and coolness at the injection site.

  • Contraindications and Kidney Risks

    • Metformin/Biguanides: Must be held for 4848 hours before and after contrast administration because the combination of contrast and Metformin increases the risk of lactic acidosis if kidney function is impaired.

    • Kidney Assessment: Kidney function (Creatinine and GFRGFR) must be assessed prior to administration because contrast is nephrotoxic. Signs of failure include oliguria, edema, and elevated laboratory markers like BUNBUN and Creatinine.