Compare drugs side-by-side

Pick 2-5 drugs to compare mechanism, dosing, PK, hemodynamics, side effects, and pearls. Useful for picking between induction agents, vasoactives, or NMBAs.

	Propofol Diprivan	Etomidate Amidate	Ketamine Ketalar
Class	Alkylphenol IV induction agent / sedative-hypnotic	Imidazole IV induction agent	Phencyclidine derivative / NMDA antagonist
Mechanism	Potentiates GABA-A chloride conductance. Direct CNS depression with no analgesia.	GABA-A potentiation. Highly hemodynamically stable due to minimal SVR/contractility effects.	Non-competitive NMDA receptor antagonist. Also effects on opioid, monoaminergic, muscarinic receptors. Produces dissociative anesthesia with analgesia.
Indications	· GA induction · TIVA maintenance · Procedural sedation · ICU sedation	· GA induction in hemodynamically unstable patients · RSI in shock	· Hemodynamically unstable induction · Bronchospasm/asthma induction · Burns dressing changes · Chronic pain (low-dose infusion)
Dosing	Induction: 1.5–2.5 mg/kg IV · peds 2.5–3.5 mg/kg IV (ages 3–16; use caution <3 yr, no data <2 mo) TIVA infusion: 100–200 mcg/kg/min · peds 200–300 mcg/kg/min (healthy children, label dose) MAC sedation: 25–75 mcg/kg/min PONV antiemetic: 10–20 mg IV bolus	Induction: 0.2–0.3 mg/kg IV · peds 0.2–0.3 mg/kg IV	Induction: 1–2 mg/kg IV · peds 1–2 mg/kg IV; 4–6 mg/kg IM (full induction) Analgesia infusion: 0.1–0.5 mg/kg/hr Sedation/analgesia bolus: 0.25–0.5 mg/kg IV Procedural sedation peds: — · peds 0.5–1 mg/kg IV repeated PRN; 3–5 mg/kg IM (dissociative, NOT induction)
PK (onset / duration)	Onset 30–45 sec. Duration 5–10 min (single bolus, redistribution). Hepatic clearance + extrahepatic. Context-sensitive half-time stays short up to 8 hr.	Onset 30–60 sec. Duration 5–10 min. Hepatic ester hydrolysis.	Onset 30 sec IV / 3–5 min IM. Duration 10–20 min IV. Hepatic CYP metabolism (norketamine metabolite still active).
Hemodynamics	↓SVR + ↓preload + mild ↓contractility → ↓BP 25–40% (Miller, 2-2.5 mg/kg induction). Blunts baroreceptor reflex; HR rise often absent or minimal.	Minimal effect — drug of choice for cardiac compromise, hypovolemia, acute trauma.	↑BP, ↑HR, ↑CO via central sympathetic stimulation. May reveal direct cardiac depression in catecholamine-depleted patients (chronic critical illness).
Respiratory	Dose-dependent apnea, blunted CO₂ response. Bronchodilatory.	Less apnea than propofol. CO₂ response preserved at induction doses.	Bronchodilator. Preserves airway reflexes + spontaneous ventilation. Increased secretions (consider glycopyrrolate).
Side effects	· Injection pain (mitigate: 40 mg lidocaine pretreat or large vein) · Hypotension (especially elderly, hypovolemic, cardiac patients) · Propofol Infusion Syndrome (PRIS) at > 4 mg/kg/hr > 48 h: lactic acidosis, rhabdo, cardiac failure · Allergy: usually formulation excipients (egg lecithin, soy oil) — true egg allergy uncommonly reactive · Green urine (benign)	· Adrenocortical suppression (11β-hydroxylase) after a single dose, for 4–8 h (Stoelting, Katzung) to up to 24 h (Barash, Nagelhout) — relevant in septic patients · Myoclonus during induction (50%) — pretreat with opioid or low-dose midaz · Injection pain in propylene glycol formulation · PONV ~30%	· Emergence reactions (vivid dreams, hallucinations) — co-administer benzo or propofol · Hypersalivation · Increased ICP (controversial in modern data — not absolute contraindication in TBI) · Tachyphylaxis with chronic infusion · Bladder symptoms with chronic recreational use
Contraindications	· Severe egg/soy/sulfite allergy (formulation-dependent)	· Septic shock with adrenal insufficiency (relative — controversial)	· Severe coronary disease (relative) · Uncontrolled HTN · Uncorrected pheochromocytoma
Reversal	—	—	—
Pearls	· Reduce dose 50% in elderly/frail/hypovolemic. · TIVA target effect-site 3–6 mcg/mL with Schnider model. · Antiemetic at doses well below sedative — useful for refractory PONV.	· Single-dose adrenal suppression mortality signal in sepsis is small but real; consider hydrocortisone supplement. · No analgesia — co-administer opioid.	· Best induction agent for status asthmaticus and cardiac tamponade. · Subanesthetic ketamine 0.25 mg/kg pre-incision reduces postop opioid + chronic pain. · S(+) enantiomer (esketamine) more potent + less psychomimetic.

Common compares

Propofol vs Etomidate vs Ketamine Sux vs Roc vs Cis Fentanyl vs Remi Phenylephrine vs Norepi Volatiles

Cells showing "—" indicate the drug doesn't have a detail entry for that field yet (most drugs do; some legacy class members haven't been fully populated). Education only — verify dosing against package insert + institutional protocol before bedside use.

Class

Alkylphenol IV induction agent / sedative-hypnotic

Imidazole IV induction agent

Phencyclidine derivative / NMDA antagonist

Mechanism

Potentiates GABA-A chloride conductance. Direct CNS depression with no analgesia.

GABA-A potentiation. Highly hemodynamically stable due to minimal SVR/contractility effects.

Non-competitive NMDA receptor antagonist. Also effects on opioid, monoaminergic, muscarinic receptors. Produces dissociative anesthesia with analgesia.

Indications

· GA induction
· TIVA maintenance
· Procedural sedation
· ICU sedation

· GA induction in hemodynamically unstable patients
· RSI in shock

· Hemodynamically unstable induction
· Bronchospasm/asthma induction
· Burns dressing changes
· Chronic pain (low-dose infusion)

Dosing

Induction: 1.5–2.5 mg/kg IV · peds 2.5–3.5 mg/kg IV (ages 3–16; use caution <3 yr, no data <2 mo)
TIVA infusion: 100–200 mcg/kg/min · peds 200–300 mcg/kg/min (healthy children, label dose)
MAC sedation: 25–75 mcg/kg/min
PONV antiemetic: 10–20 mg IV bolus

Induction: 0.2–0.3 mg/kg IV · peds 0.2–0.3 mg/kg IV

Induction: 1–2 mg/kg IV · peds 1–2 mg/kg IV; 4–6 mg/kg IM (full induction)
Analgesia infusion: 0.1–0.5 mg/kg/hr
Sedation/analgesia bolus: 0.25–0.5 mg/kg IV
Procedural sedation peds: — · peds 0.5–1 mg/kg IV repeated PRN; 3–5 mg/kg IM (dissociative, NOT induction)

PK (onset / duration)

Onset 30–45 sec. Duration 5–10 min (single bolus, redistribution). Hepatic clearance + extrahepatic. Context-sensitive half-time stays short up to 8 hr.

Onset 30–60 sec. Duration 5–10 min. Hepatic ester hydrolysis.

Onset 30 sec IV / 3–5 min IM. Duration 10–20 min IV. Hepatic CYP metabolism (norketamine metabolite still active).

Hemodynamics

↓SVR + ↓preload + mild ↓contractility → ↓BP 25–40% (Miller, 2-2.5 mg/kg induction). Blunts baroreceptor reflex; HR rise often absent or minimal.

Minimal effect — drug of choice for cardiac compromise, hypovolemia, acute trauma.

↑BP, ↑HR, ↑CO via central sympathetic stimulation. May reveal direct cardiac depression in catecholamine-depleted patients (chronic critical illness).

Respiratory

Dose-dependent apnea, blunted CO₂ response. Bronchodilatory.

Less apnea than propofol. CO₂ response preserved at induction doses.

Bronchodilator. Preserves airway reflexes + spontaneous ventilation. Increased secretions (consider glycopyrrolate).

Side effects

· Injection pain (mitigate: 40 mg lidocaine pretreat or large vein)
· Hypotension (especially elderly, hypovolemic, cardiac patients)
· Propofol Infusion Syndrome (PRIS) at > 4 mg/kg/hr > 48 h: lactic acidosis, rhabdo, cardiac failure
· Allergy: usually formulation excipients (egg lecithin, soy oil) — true egg allergy uncommonly reactive
· Green urine (benign)

· Adrenocortical suppression (11β-hydroxylase) after a single dose, for 4–8 h (Stoelting, Katzung) to up to 24 h (Barash, Nagelhout) — relevant in septic patients
· Myoclonus during induction (50%) — pretreat with opioid or low-dose midaz
· Injection pain in propylene glycol formulation
· PONV ~30%

· Emergence reactions (vivid dreams, hallucinations) — co-administer benzo or propofol
· Hypersalivation
· Increased ICP (controversial in modern data — not absolute contraindication in TBI)
· Tachyphylaxis with chronic infusion
· Bladder symptoms with chronic recreational use

Contraindications

· Severe egg/soy/sulfite allergy (formulation-dependent)

· Septic shock with adrenal insufficiency (relative — controversial)

· Severe coronary disease (relative)
· Uncontrolled HTN
· Uncorrected pheochromocytoma

Reversal

—

Pearls

· Reduce dose 50% in elderly/frail/hypovolemic.
· TIVA target effect-site 3–6 mcg/mL with Schnider model.
· Antiemetic at doses well below sedative — useful for refractory PONV.

· Single-dose adrenal suppression mortality signal in sepsis is small but real; consider hydrocortisone supplement.
· No analgesia — co-administer opioid.

· Best induction agent for status asthmaticus and cardiac tamponade.
· Subanesthetic ketamine 0.25 mg/kg pre-incision reduces postop opioid + chronic pain.
· S(+) enantiomer (esketamine) more potent + less psychomimetic.