ADMINISTRATION ROUTES:
IV, IM, PO, Nasal
ALTERNATIVE NAMES:
Hypnovel
ICU INDICATIONS:
- Sedation
- Treatment of seizures
PRESENTATION AND ADMINISTRATION:
IV:
15 mg/3 mL vial and 5 mg/5 mL vial
For direct IV injection, usually diluted to a concentration of 1 mg/mL using compatible IV fluid and injected slowly.
For continuous infusion dilute 60 mg up to a total of 60 mL with compatible IV fluid
Compatible with the following IV fluids:
Normal saline, 5% dextrose, 10% dextrose , Hartmanns
Any solutions not used within 24 hours should be discarded. Store at room temperature. Do not freeze
IM:
Inject undiluted into a large muscle mass
DOSAGE:
IV:
Sedation: 1 - 5 mg bolus Infusion: 0 - 20 mg/hr
PO:
7.5 - 15 mg (usually for anaesthesia premed)
IM:
1 - 5 mg
DOSAGE IN RENAL FAILURE AND RENAL REPLACEMENT THERAPY:
Dose in renal impairment
| GFR (ml/min) | DOSE |
|---|---|
| <10 | 50% of normal dose |
| 10-20 | dose as in normal renal function |
| >20-50 | dose as in normal renal function |
Dose in renal replacement therapy
| MODALITY | DOSE |
|---|---|
| CAPD | 50% of normal dose |
| HD | 50% of normal dose |
| CVVHDF | dose as in normal renal function |
DOSAGE IN PAEDIATRICS:
For overview of analgesia & sedation for intubated and ventilated children, see Starship guidelines:
- For 0 - 12 months: https://starship.org.nz/guidelines/picu-analgesia-and-sedation-algorithm-0-12-months-intubated-and-ventilated
- For > 12 months and < 30 kg weight: https://starship.org.nz/guidelines/picu-analgesia-and-sedation-algorithm-for-greater-than-12-months-and-30kgs
- For > 30 kg weight: https://starship.org.nz/guidelines/picu-analgesia-and-sedation-algorithm-greater-than-30kgs-intubated-and
IV:
Sedation: 0. 1 - 0.5 mg/kg
Infusion (ventilated): dilute 3 mg/kg in 50 mL 5% dextrose then run infusion at 0 - 5 mL/hr (0 - 5 mcg/kg/min)
IM:
Sedation: 0.1 - 0.5 mg/kg
Intranasal:
Sedation: 0.2 mg/kg nasal
Repeated in 10 minutes if required
PO:
Sedation: 0.5 mg/kg (max 20 mg)
CLINICAL PHARMACOLOGY:
Midazolam is a benzodiazepine. The precise mechanism by which midazolam exerts its antiseizure effect is unknown, although it is believed to be related to its ability to enhance the activity of gamma aminobutyric acid (GABA), the major inhibitory neurotransmitter in the central nervous system.
CONTRAINDICATIONS:
- Hypersensitivity to benzodiazepines
WARNINGS:
Withdrawal Symptoms
Withdrawal symptoms of the barbiturate type have occurred after the discontinuation of benzodiazepines including midazolam
PRECAUTIONS:
General:
Hypoventilation, airway obstruction, and apnoea can lead to hypoxia and/or cardiac arrest unless effective countermeasures are taken immediately.
Laboratory Tests:
No tests in addition to routine ICU tests are indicated
Drug/Laboratory Test Interactions:
None noted
IMPORTANT DRUG INTERACTIONS IN ICU:
The CNS-depressant action of the benzodiazepine class of drugs may be potentiated by alcohol, narcotics, barbiturates, nonbarbiturate hypnotics, antianxiety agents, the phenothiazines, thioxanthene and butyrophenone classes of antipsychotic agents, monoamine oxidase inhibitors and the tricyclic antidepressants, and by other anticonvulsant drugs.
ADVERSE REACTIONS:
Neurologic:
Abnormal eye movements, aphonia, choreiform movements, coma, diplopia, dysarthria, dysdiadochokinesis, 'glassy-eyed' appearance, headache, hypotonia, nystagmus, respiratory depression, slurred speech, tremor, vertigo.
Psychiatric:
Confusion, depression, amnesia, hallucinations, hysteria, increased libido, insomnia, psychosis, suicidal attempt. The following paradoxical reactions have been observed: Excitability, irritability, aggressive behaviour, agitation, nervousness, hostility, anxiety, sleep disturbances, nightmares and vivid dreams.
Respiratory:
Apnoea, hypoventilation
Cardiovascular:
Palpitations, hypotension
Haematopoietic:
Anaemia, leukopaenia, thrombocytopaenia, eosinophilia
Hepatic:
Hepatomegaly, transient elevations of serum transaminases and alkaline phosphatase