Versed
Versed
Generic Name
Versed
Mechanism
- Positive allosteric modulator of the GABA‑A receptor
- Enhances chloride ion influx → hyperpolarizes neuronal membranes → reduces excitability.
- Fast onset (IV: 1–5 min; IM: 5–10 min) and short duration due to rapid redistribution and hepatic metabolism.
- Interacts primarily with the BZD‑binding site on the GABA‑A complex, producing rapid sedation, amnesia, anxiolysis, anticonvulsant, and muscle‑relaxant effects.
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Pharmacokinetics
| Parameter | Approximate Value |
| Absorption | Rapid IV; IM ≈ 90 % bioavailability; oral <35 % |
| Onset | IV: 1–5 min; IM: 5–10 min |
| Peak effect | 5–15 min IV; 15–30 min IM |
| Distribution | Extensive; high protein binding (~80 %) |
| Metabolism | Hepatic N‑desmethylation → hydroxy‑midazolam (active) & other conjugates |
| Half‑life | 1–4 h (short‑acting); parent drug, 1–3 h; metabolites 3–12 h |
| Elimination | Renal (30–50 %) and biliary excretion |
| Drug‑drug interactions | CYP3A4 inhibitors ↑ levels; CYP3A4 inducers ↓ levels; anticholinergics & opioids potentiate CNS depression |
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Indications
- Rapid‑sequence intubation (RSI) and anesthesia induction.
- Procedural sedation (endoscopy, colonoscopy, dental, minor surgeries).
- Treatment of seizure clusters pre‑hospital.
- Anxiety management in controlled settings.
- Adjunctive therapy for intractable pain in severe acute pain cases.
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Dosing
| Setting | Typical Dose | Administration |
| Adults – Procedural sedation | 0.05–0.1 mg/kg IV (max 6 mg)** | Slow IV push, 2–4 min; repeat 0.02–0.03 mg/kg if needed |
| Adults – RSI (induction) | 0.1 mg/kg IV (max 8 mg) | Rapid IV push (≤30 s) with oxygen/air |
| Pediatrics (≤ 12 yrs) | 0.05–0.1 mg/kg IV (max 4 mg) | IV push (≤60 s) |
| Intramuscular | 0.05–0.1 mg/kg IM | Subcutaneous or intramuscular, 5–10 min onset |
• Do NOT exceed 15 mg in adults without careful monitoring.
• Use co‑administered opioids cautiously; titrate symptomatically.
• Adjust for renal/hepatic impairment and elderly.
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Adverse Effects
| Common | Serious |
| • Drowsiness, dizziness | • Severe respiratory depression (apnea, bradypnea) |
| • Hypotension | • Long‑term delirium/encephalopathy |
| • Paradoxical agitation | • Anaphylaxis (rare) |
| • Dry mouth, blurred vision | • Post‑surgical seizures (if abrupt withdrawal) |
| • Nausea & vomiting (usually transient) |
• ICU/Taking steps: rapid‑acting opioid antagonists (naloxone) may reverse respiratory depression only if opioids present.
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Monitoring
- Vital signs: HR, BP, RR, SpO₂ (every 2–5 min during sedative infusion).
- Level of consciousness: Modified Observer’s Assessment of Alertness/Sedation (MOAA/S) scores.
- Respiratory mechanics: Capnography when available.
- Electrocardiography: QT interval monitoring in prolonged infusions.
- Blood glucose in diabetics (moderate risk of hypoglycemia).
- Post‑procedure observation: at least 30 min until discharge or transfer to post‑anesthesia care.
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Clinical Pearls
- Start low, go slow: Initial ≤ 4 mg in adults; watch for hypotension especially in frail or dehydrated patients.
- Avoid rapid IV crush: Granular Versed tablets should be reconstituted and drawn into a syringe; *do not* crush and push.
- Keep an airway plan: Even small doses can precipitate apnea; have suction, oxygen, and face‑mask readily available.
- Use a “2‑mg rule” in the operating room: If sedation > 2 mg required, reassess indication or use an alternative agent (e.g., dexmedetomidine).
- In pediatrics, use weight‑based dosing and consider the *Window of 0.02 mg/kg* incremental increments to avoid oversedation.
- Paradoxical agitation is more common in the elderly; treat with a low‑dose antipsychotic (e.g., haloperidol 0.5 mg IV) if necessary.
- Same‑Day vs Overnight: For planned overnight sedation, switch to a longer‑acting benzodiazepine (e.g., lorazepam) or use a combination of midazolam IV with a continuous infusion.
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• For a deeper dive, consult the latest *American Society of Anesthesiologists* practice guidelines or *The American Family Physician* for procedural sedation.