Remimazolam
Byfavo
Ultra-short-acting benzodiazepine (procedural sedation)
GABA-A benzodiazepine agonist with an ester linkage → rapid hydrolysis by tissue esterases (like remifentanil among opioids) → fast recovery, organ-independent.
Indications
- •Procedural sedation
- •Emerging role in general anesthesia induction/maintenance
Dosing
| Context | Adult | Pediatric |
|---|---|---|
| Procedural sedation | 5 mg IV over 1 min, then 2.5 mg top-ups PRN | — |
Pharmacokinetics
Onset 1–3 min. Half-life ~7–8 min (ester hydrolysis) — organ-independent, minimal accumulation.
Hemodynamic effects
More hemodynamically stable than propofol; less hypotension.
Respiratory effects
Respiratory depression (benzodiazepine) — less than propofol but real.
Side effects
- !Respiratory depression
- !Hypotension (less than propofol)
Contraindications
- ×Benzodiazepine allergy
- ×Dextran 40 hypersensitivity (formulation)
Reversal / antidote
Flumazenil (it IS a benzodiazepine)
Clinical pearls
- ★Reversible with flumazenil (unlike propofol) + ester metabolism → fast, predictable offset.
- ★Hemodynamically gentler than propofol — attractive for fragile patients + procedural sedation.
Other drugs in Induction Agents
- Propofol
Potentiates GABA-A chloride conductance. Direct CNS depression with no analgesia.
- Etomidate
GABA-A potentiation. Highly hemodynamically stable due to minimal SVR/contractility effects.
- Ketamine
Non-competitive NMDA receptor antagonist. Also effects on opioid, monoaminergic, muscarinic receptors. Produces dissociative anesthesia with analgesia.
- Thiopental
Enhances GABA-A chloride currents (↑ channel-open duration) → rapid loss of consciousness. Classic barbiturate induction agent.
- Methohexital
GABA-A potentiation. Shorter-acting than thiopental; lowers seizure threshold (useful for ECT).
Browse all classes: /reference/drugs
Suggested reading
- •Stoelting & Hines, Pharmacology & Physiology in Anesthetic Practice, 6e
- •Miller's Anesthesia, 9e
- •FDA package insert
