Midazolam

Midazolam is a short-acting hypnotic-sedative drug with anxiolytic, muscle relaxant, anticonvulsant, sedative, hypnotic, and amnesic properties. It belongs to a class of drugs called benzodiazepines. This drug is unique from others in this class due to its rapid onset of effects and short duration of action. Midazolam is available by oral, rectal, intranasal, intramuscular (IM), and intravenous (IV) routes and has been used in various biomedical applications, including dentistry, cardiac surgery, and endoscopic procedures as pre-anesthetic medication, and as an adjunct to local anesthesia.

This drug was initially approved by the US FDA in 1985, and has been approved for various indications since. In late 2018, the intramuscular preparation was approved by the FDA for the treatment of status epilepticus in adults. In May 2019, the nasal spray of midazolam was approved for the acute treatment of distinctive intermittent, stereotypic seizure episodes in patients 12 years of age and older. Midazolam is considered a schedule IV drug in the United States due to the low potential for abuse and low risk of dependence.

Midazolam has different indications depending on its formulation by the FDA.

Nasal

For the nasal spray formulation, midazolam is indicated for the acute treatment of intermittent, stereotypic episodes of frequent seizure activity (i.e., seizure clusters, acute repetitive seizures) that are distinct from a patient’s usual seizure pattern in patients with epilepsy 12 years of age and older.

Intravenous

For the intravenous injection formulation, midazolam is indicated as an agent for sedation/anxiolysis/amnesia and prior to or during diagnostic, therapeutic or endoscopic procedures, such as bronchoscopy, gastroscopy, cystoscopy, coronary angiography, cardiac catheterization, oncology procedures, radiologic procedures, suture of lacerations and other procedures either alone or in combination with other CNS depressants. The sedative, anxiolytic and amnestic use of midazolam can also be employed pre-operatively. It can also be indicated for induction of general anesthesia, before administration of other anesthetic agents or as a component of intravenous supplementation of nitrous oxide and oxygen for a balanced anesthesia. A relatively narrower dose range of midazolam and a shorter period of induction can be achieved if midazolam is combined with narcotic premedication. Finally, midazolam can be indicated as a continous intravenous infusion for sedation of intubated and mechanically ventilated patients as a component of anesthesia or during treatment in a critical care setting.

Intramuscular

For the intramusuclar injection formulation, midazolam is indicated for preoperative sedation/anxiolysis/amnesia or for treatment of status epilepticus in adults.

Oral

Midazolam syrup is indicated for use in pediatric patients for sedation, anxiolysis and amnesia prior to diagnostic, therapeutic or endoscopic procedures or before induction of anesthesia. It is only approved in monitored settings only and not for chronic or home use.

In Europe, a buccal formulation of midazolam is also approved for the treatment of prolonged, acute, convulsive seizures in infants, toddlers, children and adolescents (from 3 months to < 18 years). For infants between 3-6 months of age treatment should be in a hospital setting where monitoring is possible and resuscitation equipment is available.