Anesthesia Medications: Contraindications & Side Effects

1. Induction Agents (IV Anesthetics)

Propofol

• Do NOT use if:

  • Egg/soy allergy (emulsion base)

  • Hypotension/shock (causes vasodilation)

• Watch for:

  • Severe hypotension, respiratory depression, bradycardia

  • Propofol Infusion Syndrome (with prolonged/high dose)

Etomidate

• Do NOT use if:

  • Sepsis/critical illness requiring cortisol (causes adrenal suppression)

• Watch for:

  • Adrenal suppression, myoclonus, nausea/vomiting

Ketamine

• Do NOT use if:

  • Severe CAD, uncontrolled HTN, ↑ICP, ↑IOP, schizophrenia

• Watch for:

  • Hypertension, tachycardia

  • Hallucinations, emergence delirium

  • Increased salivation (→ laryngospasm risk)

Thiopental (Barbiturate)

• Do NOT use if:

  • Porphyria

• Watch for:

  • Hypotension, respiratory depression, hangover effect

2. Inhaled Agents (Volatile Anesthetics)

Isoflurane, Sevoflurane, Desflurane, Halothane

• Do NOT use if:

  • History of malignant hyperthermia (life-threatening crisis)

  • Severe hypotension, intracranial hypertension (relative contraindication)

• Watch for:

  • Hypotension, arrhythmias, respiratory depression

  • Malignant hyperthermia (triggered with succinylcholine too)

  • Hepatotoxicity (esp. halothane)

3. Opioids (Analgesics)

Fentanyl, Morphine, Remifentanil, Hydromorphone

• Do NOT use if:

  • Severe respiratory depression, untreated sleep apnea, head injury with ↑ICP

• Watch for:

  • Respiratory depression, bradycardia, hypotension

  • Nausea/vomiting, constipation, urinary retention

  • Chest wall rigidity (with high-dose fentanyl/rapid IV push)

4. Neuromuscular Blockers (NMBAs)

Depolarizing: Succinylcholine

• Do NOT use if:

  • History/family hx of malignant hyperthermia

  • Burns, trauma, neuromuscular disease (↑K⁺ risk → fatal arrhythmia)

  • Severe hyperkalemia

• Watch for:

  • Hyperkalemia, arrhythmias

  • Malignant hyperthermia

  • Bradycardia (esp. children)

  • Muscle fasciculations → myalgias

Non-depolarizing: Rocuronium, Vecuronium, Cisatracurium, Pancuronium

• Do NOT use if:

  • Absolute contraindications rare, but adjust in hepatic/renal dysfunction

• Watch for:

  • Prolonged paralysis, residual weakness

  • Histamine release (esp. atracurium → hypotension, bronchospasm)

5. Reversal Agents

Neostigmine (w/ Glycopyrrolate or Atropine)

• Do NOT use if:

  • Mechanical obstruction of GI/GU tract

  • Asthma (relative, due to bronchospasm risk)

• Watch for:

  • Bradycardia, bronchospasm, salivation, abdominal cramps

Sugammadex (for Rocuronium/Vecuronium)

• Do NOT use if:

  • Severe renal impairment

• Watch for:

  • Bradycardia, anaphylaxis

  • Interferes with oral contraceptives (need backup contraception)

6. Adjuncts

Benzodiazepines (Midazolam, Lorazepam, Diazepam)

• Do NOT use if:

  • Severe respiratory depression, myasthenia gravis, acute narrow-angle glaucoma

• Watch for:

  • Respiratory depression, hypotension

  • Paradoxical agitation (rare, elderly/children)

Dexmedetomidine

• Do NOT use if:

  • Severe bradycardia, advanced heart block, severe hypotension

• Watch for:

  • Bradycardia, hypotension, rebound HTN on withdrawal

7. Local Anesthetics

Lidocaine, Bupivacaine, Ropivacaine

• Do NOT use if:

  • Allergy to amide local anesthetics

  • Severe cardiac block (esp. bupivacaine → cardiotoxic)

• Watch for:

  • CNS toxicity: tinnitus, perioral numbness, seizures

  • Cardiac toxicity: arrhythmias, hypotension, cardiac arrest

  • LAST (Local Anesthetic Systemic Toxicity) → treat with intralipid

Mnemonic for absolute red flags:

• MH → Volatiles + Succinylcholine

• K⁺ risk → Succinylcholine (burns, trauma, NM dz)

• Allergies → Propofol (egg/soy), Amide/ester locals

• Adrenal suppression → Etomidate

• Porphyria → Thiopental