Dosing and uses of Precedex (dexmedetomidine)
Adult dosage forms and strengths
injectable solution
- 100mcg/mL
ICU Sedation
Load: 1 mcg/kg IV over 10 minutes
Maintenance 0.2-1.4 mcg/kg/hr IV
Titrate less frequently than q30min to prevent hypotension
Fiberoptic Intubation
Load: 1 mcg/kg IV over 10 minutes
Maintenance 0.7 mcg/kg/hr IV
Procedural Sedation
Load: 1 mcg/kg IV over 10 minutes
Maintenance 0.6 mcg/kg/hr IV titrate to effect (usually 0.2-1 mcg/kg/hr)
Titrate less frequently than q30min to prevent hypotension
Renal Impairment
Dose reduction may be required
Hepatic Impairment
Dose reduction may be required
Pediatric dosage forms and strengths
Safety and efficacy not established
Geriatric dosage forms and strengths
Load: 0.5 mcg/kg IV over 10 minutes
Precedex (dexmedetomidine) adverse (side) effects
>10%
Hypotension (28%)
1-10%
AFiB
Anemia
Bradycardia
Fever
Pleural effusion
Leukocytosis
Pulmonary edema
Postmarketing Reports
Electrocardiogram QT prolonged
Hypernatremia
Polyuria
Warnings
Contraindications
Hypersensitivity
Cautions
Continuously monitor patients while on therapy; therapy should be administered only by persons skilled in the management of patients in the intensive care or operating room setting
Bradycardia and sinus arrest have occurred in young healthy volunteers with high vagal tone or with different routes of administration, including rapid intravenous or bolus administration
Transient hypertension reported primarily during loading dose; consider reduction in loading infusion rate
Patients can become aroused/alert with stimulation; this alone should not be considered as lack of efficacy
Prolonged exposure to dexmedetomidine beyond 24 hours may be associated with tolerance and tachyphylaxis and a dose-related increase in adverse events (eg, ARDS, respiratory failure, agitation)
Use with caution in hepatic impairment; consider dose reduction
Hypotension and bradycardia may necessitate medical intervention; may be more pronounced in patients with hypovolemia, diabetes mellitus, or chronic hypertension, and in the elderly; use with caution in patients with advanced heart block or severe ventricular dysfunction
Use with caution with concomitant administration of other vasodilators or negative chronotropic agents; use with caution due to additive pharmacodynamic effects
Potential withdrawal symptoms if abruptly withdrawn after >24 hr use
Pregnancy and lactation
Pregnancy category: C
Lactation: Excretion in milk unknown; use with 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 Precedex (dexmedetomidine)
Mechanism of action
Centrally acting alpha2-adrenoceptor agonist that has sedative and anesthetic properties possibly by activating G-proteins in the brainstem, which results in the inhibition of norepinephrine release
Pharmacokinetics
Half-life, elimination: 6 min; 2 hr (terminal)
Peak plasma: 0.3-1.5 ng/mL
Protein bound: 94%
Vd: 118 L
Metabolism: Liver, including glucuronidation and CYP2A6
Metabolites: 3-hydroxy, 3-carboxy, 3-hydroxy N-methyl, 3-carboxy N-methyl, and N-methyl O-glucuronide dexmedetomidine
Total body clearance: 39 L/hr
Excretion: Urine (95%); feces (4%)
Administration
IV Incompatibilities
Y-site: ampho B, diazepam
IV Compatibilities
Solution: D5W, LR, NS, mannitol 20%
Y-site (partial list): amiodarone, cefepime, cefoperazone, ceftriaxone, chlorpromazine, ciprofloxacin, clindamycin, digoxin, diphenhydramine, dobutamine, dopamine, epinephrine, fluconazole, furosemide, heparin, hydroxyzine, labetalol, lidocaine, linezolid, lorazepam, meperidine, metoclopramide, MgSO4, metronidazole, KCl, nitroglycein, prochlorperazine, promethazine, NaHCO3, Na-nitroprusside, TMP-SMX, vancomycin, verapamiL
Not Spec: atracurium, atropine, etomidate, fentanyl, glycopyrrolate, midazolam, mivacurium, morphine, pancuronium, phenylephrine, succinylcholine, thiopental, vecuronium
IV Preparation
Dilute in Ns
IV Administration
Use controlled infusion device; use components made with synthetic or coated natural rubber gaskets
Infuse loading dose over 10 min