What Factors Affect Midazolam Dosage?

Midazolam injection, 1. Dosing before anesthesia. 2. General anesthesia induction and maintenance. 3 Adjuvant medication for spinal canal and local anesthesia. 4 Patients are sedated during diagnostic or therapeutic procedures (eg, angiography, cardioversion, bronchoscopy, gastrointestinal endoscopy, etc.). 5. ICU patients were sedated.

Midazolam injection, 1. Dosing before anesthesia. 2. General anesthesia induction and maintenance. 3 Adjuvant medication for spinal canal and local anesthesia. 4 Patients are sedated during diagnostic or therapeutic procedures (eg, angiography, cardioversion, bronchoscopy, gastrointestinal endoscopy, etc.). 5. ICU patients were sedated.

Drug Name

Midazolam injection

Drug type

Work Injury Medical Insurance Class A Double Span

Hanyu Pinyin

Mi Da Zuo Lun Zhu She Ye

Use classification

Benzodiazepines

Warning Signs for Midazolam Injection

It is strictly prohibited for food and feed processing.

Midazolam injection composition

Main ingredients: Midazolam hydrochloride.
The chemical name of midazolam hydrochloride is: 8-chloro-6- (2-fluorophenyl) -1-methyl-4H-imidazo [1,5-a] [1,4] benzobis The chemical structural formula of azepine hydrochloride is:

Molecular formula: C ₁₈ H ₁₃ ClFN ₃ · HCl
Molecular weight: 362.2

Characteristics of Midazolam Injection

This product is colorless or almost colorless clear liquid.

Indications of midazolam injection

1. Dosing before anesthesia.
2. General anesthesia induction and maintenance.
3 Adjuvant medication for spinal canal and local anesthesia.
4 Patients are sedated during diagnostic or therapeutic procedures (eg, angiography, cardioversion, bronchoscopy, gastrointestinal endoscopy, etc.)
5. ICU patients were sedated.

Midazolam injection specifications

1) 2ml: 2mg 2) 5ml: 5mg

Midazolam injection usage and dosage

This product is a strong sedative, the injection speed should be slow, and the dosage should be determined according to clinical needs, the patient's physiological state, age and compatibility.
1. Intramuscular injection is diluted with 0.9% sodium chloride injection. Intravenous administration was diluted with 0.9% sodium chloride injection, 5% or 10% glucose injection, 5% fructose injection, Ringer's solution.
2. Administration before anesthesia is used 20-60 minutes before the induction of anesthesia, the dosage is 0.05-0.075mg / kg intramuscular injection, the dose of elderly patients should be reduced; general anesthesia induction is usually 5-10mg (0.1-0.15mg / kg).
3, local anesthesia or spinal canal anesthesia adjuvant medication, intravenous injection 0.03-0.04mg / kg.
4. ICU patients are sedated, and intravenously inject 2-3 mg, followed by intravenous infusion of 0.05 mg / (kg · h).

Adverse reactions of midazolam injection

1. The more common adverse reactions are drowsiness, sedation, headache, hallucinations, ataxia, hiccups, and laryngospasm.
2. Intravenous injection can also cause respiratory depression and blood pressure drop, and very few can occur apnea, cessation or cardiac arrest. Sometimes thrombophlebitis can occur;
3. Rectal administration, some patients may have euphoria.

Midazolam injection contraindications

Patients allergic to benzodiazepine, patients with myasthenia gravis, schizophrenia, and severe depression are disabled.

Precautions for Midazolam Injection

1. It is often used for a long time after sleep induction after general anesthesia induction. Care should be taken to keep the patient's airway open.
2. This product cannot be diluted or mixed with 6% dextran injection or alkaline injection.
3 Long-term intravenous midazolam, sudden withdrawal can cause withdrawal syndrome, and it is recommended to gradually reduce the dose.
4 Do not leave the hospital or clinic for at least 3 hours after intramuscular or intravenous midazolam injection, and leave with someone afterwards. Do not drive or operate machinery for at least 12 hours.
5. It should be used with caution in patients with weak constitution or patients with chronic disease, pulmonary obstructive disease, chronic renal failure, liver damage or congestive heart failure. If midazolam is used, the dose should be reduced and vital signs monitored.
6. This product can only be used for one patient at a time, and the remaining product must be discarded after use.

Midazolam injection for pregnant and lactating women

1. Midazolam cannot be used in pregnant women. Special attention should be paid to the application during delivery. A single large-dose injection can cause respiratory depression, hypotonia, decreased body temperature, and weak suction.
2, Midazolam can be secreted with milk, usually not used in lactating women.

Midazolam injection for children

The test was not performed and there are no reliable references.

Midazolam injection for the elderly

Elderly people over 60 are among the high-risk patients.

Drug interactions of midazolam injection

1. Midazolam enhances the central inhibitory effects of hypnotics, sedatives, anxiolytics, antidepressants, antiepileptics, narcotics and sedative antihistamines.
2. Some liver enzyme inhibitors, especially cytochrome P450 3A inhibitors, can affect the pharmacokinetics of midazolam and prolong its sedative effect.
3 Alcohol can enhance the sedative effect of midazolam.

Midazolam injection overdose

1. Overdose generally manifests as an increase in pharmacological effects: central inhibition-from excessive sedation to coma, mental disorders, lethargy, muscle relaxation or abnormal excitement. In most cases, you only need to pay attention to monitoring vital signs.
2. Severe overdose can cause coma, disappearance of reflexes, suppression of respiratory circulation and suffocation, corresponding measures need to be taken (artificial breathing, circulatory support), and reversal with benzodiazepine receptor antagonists such as flumazenil.

Pharmacology and Toxicology of Midazolam Injection

Animal test results show that this product has obvious sedative, muscle relaxant, anticonvulsant, and anxiolytic pharmacological effects. Results of acute toxicity in mice were venous LD50, 91.32mg / kg for males and 93.26mg / kg for females; LD50, 240.05mg / kg for males and 212.82mg / kg for females.

Pharmacokinetics of Midazolam Injection

According to literature reports, this product is rapidly and completely absorbed by intramuscular administration, and the bioavailability is as high as 90% or more. This product is completely metabolized in the body, the main metabolite is hydroxymidazolam, and then quickly combines with glucuronic acid to present an inactive metabolite. 60% to 70% of the dose is excreted by the kidneys. The volume of steady state distribution for intravenous administration can reach 50 to 60 liters, the plasma protein binding rate is about 95%, the blood clearance rate is 300 to 400 ml / min, and the half-life is 1.5 to 2.5 hours.

Storage of Midazolam Injection

Keep away from light and keep tightly closed.

Midazolam injection packaging

1) 2ml: 2mg ampoule, 5 pieces / box 2) 5ml: 5mg ampoule, 5 pieces / box

Validity of Midazolam Injection

24 months.

Midazolam injection standard

First Supplement of the Chinese Pharmacopoeia 2010

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