From the Guidelines
For conscious sedation, midazolam is recommended to be administered intravenously at an initial dose of 1 to 2 mg over 1 to 2 minutes for healthy adults younger than 60 years of age, with additional doses of 1 mg administered at 2-minute intervals as needed, up to a maximum total dose of 6 mg, as this regimen has been shown to provide effective sedation while minimizing the risk of adverse effects 1. The dosing regimen for midazolam should be adjusted based on patient factors, such as age and physical status, with elderly or debilitated patients requiring a dose reduction of 20% or more. Key considerations for the use of midazolam in conscious sedation include:
- Onset of action: 1 to 2 minutes
- Peak effect: 3 to 4 minutes
- Duration of effect: 15 to 80 minutes
- Potential for synergistic interaction with opioids, requiring a reduction in the dose of midazolam
- Importance of continuous monitoring of vital signs, including oxygen saturation, heart rate, and blood pressure, throughout the procedure
- Availability of flumazenil as a reversal agent in case of adverse effects, such as respiratory depression. The most recent and highest quality study, published in 2012, provides the basis for these recommendations, and its findings are consistent with those of earlier studies, such as the 2007 AGA Institute review of endoscopic sedation 1.
From the FDA Drug Label
When used for sedation/anxiolysis/amnesia for a procedure, dosage must be individualized and titrated. Midazolam should always be titrated slowly; administer over at least 2 minutes and allow an additional 2 or more minutes to fully evaluate the sedative effect. For continuous infusion, midazolam 5 mg/mL formulation is recommended diluted to a concentration of 0.5 mg/mL with 0.9% sodium chloride or 5% dextrose in water. Usual Adult Dose: If a loading dose is necessary to rapidly initiate sedation, 0.01 to 0.05 mg/kg (approximately 0.5 to 4 mg for a typical adult) may be given slowly or infused over several minutes. For maintenance of sedation, the usual initial infusion rate is 0.02 to 0.10 mg/kg/hr (1 to 7 mg/hr).
The recommended dosing regimen for midazolam for conscious sedation is:
- Initial dose: 0.01 to 0.05 mg/kg (approximately 0.5 to 4 mg for a typical adult) given slowly or infused over several minutes.
- Maintenance dose: 0.02 to 0.10 mg/kg/hr (1 to 7 mg/hr) titrated to the desired level of sedation.
- Titration: Midazolam should always be titrated slowly, administering over at least 2 minutes and allowing an additional 2 or more minutes to fully evaluate the sedative effect.
- Key considerations:
- Individualize the dose based on the patient's age, clinical status, and current medications.
- Use the lowest recommended doses in patients with residual effects from anesthetic drugs or those concurrently receiving other sedatives or opioids.
- Assess sedation at regular intervals and adjust the midazolam infusion rate as needed.
- Decrease the infusion rate by 10% to 25% every few hours to find the minimum effective infusion rate 2.
From the Research
Recommended Dosing Regimen for Midazolam
The recommended dosing regimen for midazolam for conscious sedation is as follows:
- For preoperative sedation, the recommended dose is 0.07-0.1 mg/kg given by intramuscular injection one hour before surgery 3.
- For conscious sedation, 0.1-0.15 mg/kg intravenously in divided doses is usually adequate 3.
- Lower doses of midazolam are recommended for elderly or debilitated patients and patients who have severe liver disease 3.
Comparison with Other Benzodiazepines
Midazolam has been compared to other benzodiazepines, such as diazepam, for conscious sedation:
- Midazolam causes less pain on injection, a significantly greater degree of early sedation, and a more rapid return to baseline function compared to diazepam 4.
- Midazolam is approximately two to four times as potent as diazepam 3.
Safety and Efficacy
The safety and efficacy of midazolam for conscious sedation have been established in various studies:
- Midazolam is a good premedicant for general or regional anesthesia and is well tolerated 3.
- Conscious sedation with intermittent midazolam and fentanyl is safe and efficacious for a broad range of electrophysiology procedures 5.
- The use of flumazenil, a benzodiazepine receptor antagonist, provides flexibility and added safety for intravenous benzodiazepine sedation 6.