Pharmacology Review – High-Yield Medications

Smoking-Cessation Agent

• Varenicline (Chantix) – partial nicotinic receptor agonist/antagonist.
  • Mechanism: occupies α4β2 nicotinic ACh receptors → blocks nicotine-induced dopamine surge → smoking becomes unrewarding.
  • Dosing & timing
  • Begin 1 week before target quit date.
  • Typical total course 12 weeks; may repeat if relapse.
  • Adverse effects
  • Nausea, anorexia/↓weight
  • Vivid/unusual dreams
  • Mood change, depression, suicidal ideation – educate family to monitor.
  • Patient education
  • Continue smoking during titration week, then stop.
  • Take after food with full glass water to limit nausea.
  • Report mood changes immediately.

Loop Diuretic

• Furosemide (Lasix) – inhibits Na⁺/K⁺/2Cl⁻ cotransporter in ascending loop of Henle.
  • Uses: pulmonary oedema, CHF, renal failure, HTN with CKD.
  • Forms & kinetics
  • IV onset ≈ 5 min ("rapid Lasix").
  • Oral onset ≈ 60 min.
  • Also IM, sub-lingual.
  • Side effects / monitoring
  • \text{Hypokalemia},\; hyponatremia,\; hypocalcemia
  • Ototoxicity → tinnitus if IV pushed too fast; obtain baseline hearing & avoid rapid bolus.
  • Sulfa cross-allergy – confirm history.
  • Nursing
  • Expect ↑urine within drug-specific onset; no output → check catheter patency, then reassess.
  • Daily weight, electrolytes, orthostatic BP.

Fluoroquinolone Antibiotic

• Levofloxacin (Levaquin)
  • Broad use: CAP, sinusitis, skin & soft tissue infections.
  • Key toxicities
  • Tendinitis, risk of Achilles tendon rupture (↑ with steroids, elderly).
  • Photosensitivity – sunscreen, protective clothing.
  • If joint pain appears
  • Stop drug immediately, place patient on bed rest, notify provider.

HMG-CoA Reductase Inhibitor (Statin)

• Atorvastatin (Lipitor)
  • Lowers total cholesterol, LDL; modest ↓triglycerides, slight ↑HDL.
  • Dangerous adverse effects
  • Hepatotoxicity – monitor AST/ALT (LFTs).
  • Rhabdomyolysis – check CK, monitor for myalgia, dark urine, weakness; UA for protein.
  • Avoid grapefruit (CYP3A4) & alcohol (added liver strain).
  • Effectiveness → trend lipid panel periodically.

Phosphodiesterase-5 Inhibitor

• Sildenafil (Viagra)
  • Uses: erectile dysfunction; also PAH (lower pulmonary vascular resistance).
  • Side effects: flushing, headache, hypotension, blurry vision (blue tint), myocardial infarction, priapism.
  • Priapism >4 h = emergency → ED for needle aspiration ↓ischemia.
  • Absolute contraindication with nitrates (e.g. nitroglycerin) → catastrophic hypotension.
  • Verify med list (common in veteran population).

Selective Serotonin Re-uptake Inhibitor

• Sertraline (Zoloft)
  • Indications: depression, PTSD, OCD, panic disorder.
  • Adverse: weight change, somnolence, sexual dysfunction, hallucination (rare), GI upset.
  • MAOI wash-out: wait 14 days to prevent serotonin syndrome.
  • Serotonin-syndrome S/S: agitation, diaphoresis, hyper-BP, diarrhea, myoclonus, hyperreflexia, tremor.
  • No abrupt stop; taper slowly.
  • Avoid alcohol (CNS depression, ↑sedation).

Transdermal Opioid Analgesic

• Fentanyl Patch (Duragesic)
  • For severe chronic pain unresponsive to other opioids (cancer, hospice).
  • Onset to full effect ≈ 24 h; patch worn 72 h then rotate site.
  • Provide short-acting analgesic during first 24 h & for breakthrough pain.
  • Risks: respiratory depression, constipation, dependence.

Nasal / Inhaled Corticosteroids

• Fluticasone (Flonase/Flovent)
  • Rhinitis (seasonal & perennial); inhaled combo + salmeterol (Advair) for asthma/COPD.
  • LABA component: Salmeterol – long-acting β_2 agonist → broncho-dilation.
  • Side effects: nausea, dizziness, epistaxis, hoarseness, oropharyngeal candidiasis.
  • Administration
  • Use DAILY, not PRN.
  • Rinse & gargle post-use to prevent thrush; use spacer if inhaler.
  • Avoid grapefruit (↑ systemic level).

Non-selective Beta Blocker

• Propranolol (Inderal)
  • Uses: HTN, dysrhythmia, migraine prophylaxis, performance anxiety.
  • Beta1 & Beta2 block → bradycardia, ↓CO, bronchoconstriction, depression.
  • Special cautions
  • Asthma/COPD – may precipitate bronchospasm.
  • Diabetes – masks tachycardia of hypoglycemia & inhibits glycogenolysis.
  • Severe allergy – may blunt epinephrine rescue.
  • Black-box: abrupt withdrawal → rebound angina/MI. Taper.
  • First-dose syncope; advise bedtime dose, no driving 12$–$24 h.
  • Hold if HR <60 bpm or SBP <100 mmHg (facility protocol).

Cholinesterase Inhibitor for Alzheimer’s

• Donepezil (Aricept)
  • Improves cognition in mild → severe Alzheimer disease.
  • Side effects: N/V/D, GI bleed, anorexia, dizziness, bronchoconstriction, bradycardia, ↓reaction time.
  • Start low dose; take DAILY (not alternate days).
• Memantine (Namenda) – NMDA receptor antagonist; add for moderate-to-severe disease.

Cross-Topic Nursing Themes

• Check medication lists & OTCs for dangerous interactions (nitrates + sildenafil; other serotonergic drugs + SSRIs; grapefruit + CYP3A4 substrates).
• Educate on timing/onset to set expectations (varenicline start 1 wk early; fentanyl patch needs 24 h).
• Baseline data before high-risk drugs
  • Hearing test for furosemide
  • LFT/CK before statin
  • Vital signs & lung status before propranolol
• Taper agents with CNS activity (SSRIs, beta blockers) to avoid rebound / withdrawal.
• Highlight emergency signs patients must report: priapism >4 h, sudden tendon pain, red-brown urine (rhabdo), worsening depression or suicidality, ototoxic S/S.