Medication Administration — Comprehensive Study Notes Summary & Study Notes

🚚 Routes of Administration

Enteral (via GI tract): Oral (PO) is the safest, cheapest, most common. Sublingual (SL) (under tongue) and buccal (between cheek and gum) bypass some first-pass metabolism. NG/PEG tubes used when patient cannot swallow.

Parenteral (bypasses GI): IV = fastest onset and most dangerous. IM into deltoid, vastus lateralis, ventrogluteal (ventrogluteal preferred in adults). SubQ into fat for insulin and heparin (slower, sustained). Intradermal (ID) is the shallowest (TB and allergy testing).

Topical / Other: Transdermal patches for slow systemic release. Inhalation for rapid pulmonary absorption (e.g., bronchodilators). Rectal/Vaginal for NPO, vomiting, or unconscious patients. Epidural/Intrathecal for spinal administration (pain management).

Exam tips: IV = fastest. ID = shallowest. SubQ = insulin/heparin. Ventrogluteal = preferred adult IM site.

✅ The Rights of Medication Administration

Core 6 Rights (high-yield): Right Patient, Right Medication, Right Dose, Right Route, Right Time, Right Documentation. Many programs extend to 9–10 rights (include Right Reason, Right Response, Right to Refuse, Right Education).

Always use two patient identifiers (name + DOB or MRN). Verify allergies before any med. Document immediately after giving; never document before. The Right to Refuse is a legal patient right — respect and document refusal.

⚠️ Reactions: Side Effects vs Adverse vs Allergic vs Idiosyncratic

Side effects: Predictable, dose-related, generally not dangerous (e.g., nausea from antibiotics, drowsiness from antihistamines, dry mouth from anticholinergics, constipation from opioids). Nursing action: educate, manage symptoms, do not automatically stop medication.

Adverse effects: Harmful, unintended, often more severe and can cause organ damage (e.g., hepatotoxicity from acetaminophen overdose, nephrotoxicity from aminoglycosides/NSAIDs, ototoxicity from furosemide/aminoglycosides, bone marrow suppression from chemo, GI bleeding from NSAIDs/aspirin). Nursing action: monitor labs, assess symptoms, may require dose reduction or stopping drug, and report immediately.

Allergic reactions: Immune-mediated; require prior sensitization. Types:

• Type I (Anaphylaxis): Immediate (minutes) — e.g., penicillin, bee sting. Signs: bronchospasm, laryngeal edema, hypotension, tachycardia.
• Type II (Cytotoxic): Hours — e.g., drug-induced hemolytic anemia.
• Type III (Immune complex): Hours–days — e.g., serum sickness.
• Type IV (Delayed): 48–72 hours — e.g., contact dermatitis.

Anaphylaxis treatment sequence: STOP the drug → call for help → Epinephrine 1:1000 IM (vastus lateralis) → secure airway/oxygen → diphenhydramine → corticosteroids → IV fluids.

Idiosyncratic reactions: Abnormal, unpredictable, often genetically based and not immune-mediated. Examples: primaquine causing hemolytic anemia in G6PD deficiency; succinylcholine triggering malignant hyperthermia; codeine ultra-metabolism leading to toxicity; isoniazid (INH) causing peripheral neuropathy in slow acetylators. Key difference: allergic = immune system involved; idiosyncratic = genetic/unknown, no immune involvement.

📊 Quick Comparison (high-yield distinctions)

• Predictable: Side effects (yes), Adverse (often), Allergic (no), Idiosyncratic (no)
• Immune-mediated: Allergic (yes), others (no)
• Dose-related: Side effects (yes), Adverse (often), Allergic/Idiosyncratic (no)
• Severity: Side effects (mild), Adverse (moderate–severe), Allergic (mild–fatal), Idiosyncratic (variable)

🩺 Clinical Priorities & Nursing Actions

Before any medication: assess allergies (ask patient and check chart/allergy band). Verify the core rights and reason for medication. Always know why a drug is ordered (Right Reason).

If signs of anaphylaxis occur: STOP medication, call for help, and administer epinephrine promptly. Document events and interventions thoroughly.

Document medication administration immediately after giving. Assess patient response after administration and report adverse findings.

🎯 High-Yield Exam Tips

• Memorize: IV = fastest; ID = shallowest; Ventrogluteal = preferred adult IM site; SubQ commonly used for insulin and heparin.
• Core 6 Rights are the most tested — know them and your program’s version (some use 9 or 10).
• Distinguish allergic vs idiosyncratic reactions on exams: immune vs genetic/unknown.
• Practice active recall on the comparison of reaction types and anaphylaxis steps; these are frequent exam topics.