Dosing and uses of Amidate (etomidate)
Adult dosage forms and strengths
injectable solution
- 2mg/mL
General Anesthesia Induction
0.3-0.6 mg/kg IVP over 30-60 sec
Cushing Syndrome (Off-label)
Inhibition of steroidogenesis in patients with Cushing syndrome
0.2-0.6 mg/kg IV infused over 30-60 seconds for induction of anesthesia blocks normal stress-induced increase in adrenal cortisol production for 4-8 h
ICU continuous infusion: 0.04-0.05 mg/kg/hr IV; continuous monitoring required
Dosing considerations
- Used rarely; often toxic at doses required to reduce cortisol secretion
- Long-term use limited by the requirement for repeated IV administration
Sedation (Off-label)
0.1 mg/kg IV bolus x1-3 doses; other dosing regimens may exist
Pediatric dosage forms and strengths
injectable solution
- 2mg/mL
General Anesthesia Induction
<10 years: Safety and efficacy not established
>10 years: Same as adults; 0.3-0.6 mg/kg IVP over 30-60 sec
Sedation (Off-label)
0.1-0.4 mg/kg IV bolus x1; additional doses may be necessary; other dosing regimens may exist
Amidate (etomidate) adverse (side) effects
>10%
Transient injection site pain (30-80%)
Skeletal muscle movements, mainly myoclonic (32%)
Opsoclonus (20%)
Adrenal suppression
1-10%
Hiccups
<1%
Apnea (duration: 5-90 seconds)
Arrhythmias
Hyperventilation
HTn
Hypotension
Hypoventilation
Laryngospasm
Nausea/vomiting
Oxygen desaturation
Snoring (may be associated with partial upper airway obstruction)
Warnings
Contraindications
Hypersensitivity
Controversial: Sepsis, septic shock
Cautions
Lack of ventilatory support
Adrenal suppression (and prolonged therapy)
Prolonged IV infusion not recommended
Safety during labor and delivery not elucidated; not recommended
Pregnancy and lactation
Pregnancy category: C
Lactation: Not known if excreted in breast milk; use caution
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Amidate (etomidate)
Mechanism of action
Nonbarbiturate hypnotic used for the induction of anesthesia; lacks analgesic activity; has minimal cardiovascular effects
Cushing syndrome (off-label): Blocks 11-beta-hydroxylase
Blocks steroidogenesis; 0.3 mg/kg will reduce plasma cortisol for up to 24 hr
Does not affect cardiac metabolism; no depression of cardiac output or of peripheral or pulmonary circulation
Absorption
Onset: Within 60 sec
Duration: 3-5 min due to redistribution from CNs
Distribution
Protein bound: 76%
Vd: 2-4.5 L/kg
Metabolism
Hepatic and plasma esterases
Elimination
Excretion: Urine, as inactive agent
Administration
IV Incompatibilities
Y-site: Ascorbic acid, vecuronium
IV Compatibilities
Syringe: Heparin
Y-site: Alfentanil, atracurium, atropine, ephedrine, fentanyl, lidocaine, lorazepam, midazolam, mivacurium, morphine sulfate, pancuronium, phenylephrine, succinylcholine, sufentaniL
IV Administration
Inject undiluted by direct IV injection over 30-60 sec; do not administer by prolonged IV infusion
Inject into large forearm vein
Consider lidocaine preadministration to minimize injection-site pain
