Dexmedetomidine

Buccal, Sublingual
Acute agitation associated with bipolar I or II disorder, Acute agitation associated with schizophrenia

Intravenous
Sedation in critical care

Intravenous
Sedation in minor surgical and medical procedures

Intravenous:
Dose reduction may be needed.

Sublingual/Buccal:
Mild to moderate (Child-Pugh Class A or B): Initially, 90 mcg (mild to moderate agitation); 120 mcg (severe agitation). If agitation persists, may give additional 2 doses of 60 mcg at least 2 hours apart. Max: 210 mcg (mild to moderate agitation); 240 mcg daily (severe agitation). Severe impairment (Child-Pugh Class C): Initially, 60 mcg (mild to moderate agitation); 90 mcg (severe agitation). If agitation persists, may give additional 2 doses of 60 mcg at least 2 hours apart. Max: 180 mcg (mild to moderate agitation); 210 mcg daily (severe agitation).

Dilute vial labelled as containing 100 mcg/mL in NaCl 0.9% solution for inj to a final concentration of 4 mcg/mL.

Incompatible with amphotericin B, and diazepam.

Grade 2 or 3 advanced heart block (unless paced), uncontrolled hypotension, acute cerebrovascular disorders.

Patient with severe neurological disorders, bradycardia, ischaemic heart disease, peripheral autonomic activity, chronic hypertension, severe ventricular dysfunction, hypovolaemia, diabetes mellitus. Avoid abrupt withdrawal after prolonged use. Renal and hepatic impairment. Elderly. Pregnancy and lactation.

Significant: Hyperthermia or pyrexia, tolerance, tachyphylaxis, withdrawal syndrome, transient hypertension, sinus arrest.
Cardiac disorders: Tachycardia, atrial fibrillation.
Gastrointestinal disorders: Oral hypoaesthesia, constipation, nausea, vomiting.
Metabolism and nutrition disorders: Hypo- or hyperglycaemia.
Nervous system disorders: Agitation, anxiety, drowsiness, dizziness, paraesthesia.
Respiratory, thoracic and mediastinal disorders: Hypoxia, bradypnoea, respiratory depression.
Potentially Fatal: Hypotension, bradycardia.

IV/Parenteral: C

This drug may occasionally cause dizziness or drowsiness, if affected, do not drive or operate machinery for at least 8 hours after administration.

Monitor cardiac and respiratory function, level of sedation, blood pressure, pain control.

Symptoms: Bradycardia, hypertension (more prominent), hypotension, oversedation, somnolence, first degree atrioventricular block, second degree heart block, cardiac arrest. Management: Symptomatic treatment. Treat sinus arrest with atropine and glycopyrrolate.

Enhanced pharmacologic effects with anaesthetics, sedatives, hypnotics, opioids.

Description:
Mechanism of Action: Dexmedetomidine is a selective α₂-adrenoceptor agonist with anxiolytic, anaesthetic, and sedative properties. Its action is thought to be due to the activation of G-proteins by α_2a-adrenoceptors in the brainstem, resulting in inhibition of norepinephrine release in the sympathetic nerve endings.
Onset: 5-10 minutes.
Duration: 60-240 minutes.
Pharmacokinetics:
Distribution: Crosses the placenta, enters breast milk. Volume of distribution: Approx 118 L. Plasma protein binding: Approx 94%, mainly to albumin.
Metabolism: Almost completely metabolised in the liver by CYP2A6 enzyme via direct N-glucuronidation, N-methylation, and oxidation.
Excretion: Via urine (95%) and faeces (4%), mainly as metabolites. Terminal elimination half-life: Approx 2 hours.

Source: National Center for Biotechnology Information. PubChem Compound Summary for CID 5311068, Dexmedetomidine. https://pubchem.ncbi.nlm.nih.gov/compound/Dexmedetomidine. Accessed Oct. 25, 2023.

Store between 20-25°C.

Hypnotics & Sedatives

N05CM18 - dexmedetomidine ; Belongs to the class of other hypnotics and sedatives.

Anon. Dexmedetomidine. AHFS Clinical Drug Information [online]. Bethesda, MD. American Society of Health-System Pharmacists, Inc. https://www.ahfscdi.com. Accessed 04/03/2023.

Anon. Dexmedetomidine. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 04/03/2023.

Buckingham R (ed). Dexmedetomidine Hydrochloride. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 04/03/2023.

Dexmedetomidine 4 micrograms/mL Solution for Infusion (Altan Pharma Ltd). MHRA. https://products.mhra.gov.uk. Accessed 04/03/2023.

Dexmedetomidine Hydrochloride Injection, Solution, Concentrate (Akorn). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed. Accessed 04/03/2023.

Igalmi Sublingual Film for Sublingual or Buccal Use (BioXcel Therapeutics, Inc.). U.S. FDA. https://www.fda.gov. Accessed 16/05/2023.

Joint Formulary Committee. Dexmedetomidine. British National Formulary [online]. London. BMJ Group and Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 04/03/2023.

Pfizer New Zealand Limited. Precedex 100 micrograms/mL Concentrate for Infusion data sheet 28 October 2022. Medsafe. http://www.medsafe.govt.nz. Accessed 04/03/2023.

Precedex Injection (Hospira Malaysia Sdn Bhd). National Pharmaceutical Regulatory Agency - Ministry of Health Malaysia. https://www.npra.gov.my. Accessed 04/03/2023.