Alpha-2 Agonist Sedative Pregnancy: Limited data in pregnant women; animal studies have shown reproductive toxicity. Should not be used during pregnancy unless the clinical condition of the woman requires treatment. Milk levels fall below detection by 24 hours after discontinuation; a risk to the infant cannot be excluded.

Dexmedetomidine

Brand names: Precedex, Dexdor

Dexmedetomidine is a selective alpha-2 adrenoceptor agonist used for sedation of intubated and ventilated patients in intensive care and for procedural sedation, providing sedation with relative preservation of respiratory drive.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: ICU sedation (adults already intubated and sedated): initial IV infusion 0.7 micrograms/kg/hour, then adjusted stepwise within the range 0.2 to 1.4 micrograms/kg/hour to achieve the desired sedation level (target RASS 0 to -3). A lower starting rate should be considered for frail patients. Use of a loading dose is NOT recommended in ICU sedation.

Route: Intravenous infusion only, diluted, via a controlled infusion device

Frequency: Continuous infusion, titrated to response (a new steady-state sedation level may take up to one hour after each adjustment)

Max: 1.4 micrograms/kg/hour must not be exceeded; patients not adequately sedated at the maximum dose should be switched to an alternative sedative

Procedural / awake sedation (non-intubated adults): loading infusion of 1.0 microgram/kg over 10 minutes (0.5 micrograms/kg over 10 minutes may suit less invasive procedures such as ophthalmic surgery), followed by maintenance generally initiated at 0.6 to 0.7 micrograms/kg/hour and titrated within 0.2 to 1 microgram/kg/hour. No experience beyond 14 days of use - reassess regularly. Elderly: no routine dose adjustment but increased risk of hypotension, especially over 65 years - consider dose reduction. Hepatic impairment: use with caution, consider a reduced maintenance dose. PAEDIATRIC (0 to 18 years): safety and efficacy not established - no posology recommendation can be made. NOTE: US labelling limits administration duration to 24 hours and gives an ICU maintenance range of 0.2 to 0.7 micrograms/kg/hour (differs from UK SPC).

Dose adjustments

Renal

No dose adjustment is required for patients with renal impairment.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to dexmedetomidine or to any of the excipients
Advanced heart block (grade 2 or 3) unless paced
Uncontrolled hypotension
Acute cerebrovascular conditions

Side effects

Hypotension (very common)
Hypertension (very common)
Bradycardia (very common)
Respiratory depression (very common)
Nausea, vomiting and dry mouth
Hyperglycaemia or hypoglycaemia

Interactions

Anaesthetics, sedatives, hypnotics and opioids (e.g. sevoflurane, isoflurane, propofol, alfentanil, midazolam): enhancement of effects - a reduction in the dose of dexmedetomidine or of the concomitant agent may be required
Other substances with sedative or cardiovascular (e.g. negative chronotropic/vasodilator) actions: additive effects - use with caution

Clinical monograph

How it works

It stimulates central alpha-2 adrenoceptors, reducing sympathetic outflow and noradrenaline release to produce dose-dependent sedation, anxiolysis and analgesia.

Prescribing in practice

It commonly causes bradycardia and hypotension, which can be pronounced, so close haemodynamic monitoring is essential and a loading approach may need to be avoided in vulnerable patients.
It provides cooperative, rousable sedation with less respiratory depression than many alternatives, which can facilitate weaning and assessment.
Abrupt withdrawal after prolonged infusion may cause rebound hypertension, agitation and tachycardia, so tapering should be considered.

Monitoring

Continuously monitor heart rate, blood pressure, ECG, sedation level and respiratory status throughout the infusion.

Counselling the patient

Reassure conscious patients that they may feel calm but can still be roused and communicate.
Alert the team to watch for and treat bradycardia and hypotension.

Evidence & guidelines

Its sedative role is supported by critical-care evidence and practice, with administration by appropriately monitored, experienced teams.

Reference: MENDS2 trial (NEJM 2021); ESICM Sedation Guidelines; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Pathways