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
Midazolam is sometimes used for the acute management of seizures. Long-term use for the management of epilepsy is not recommended due to the significant risk of tolerance (which renders midazolam and other benzodiazepines ineffective) and the significant side effect of sedation. A benefit of midazolam is that in children it can be given in the cheek or in the nose for acute seizures, including status epilepticus.
Midazolam is effective for status epilepticus that has not improved following other treatments or when intravenous access cannot be obtained, and has advantages of being water-soluble, having a rapid onset of action and not causing metabolic acidosis from the propylene glycol vehicle, which occurs with other benzodiazepine.
Intravenous midazolam is indicated for procedural sedation (often in combination with an opioid, such as fentanyl), for preoperative sedation, for the induction of general anesthesia, and for sedation of people who are ventilated in critical care units. Midazolam is superior to diazepam in impairing memory of endoscopy procedures, but propofol has a quicker recovery time and a better memory-impairing effect.
It is the most popular benzodiazepine in the intensive care unit (ICU) because of its short elimination half-life, combined with its water solubility and its suitability for continuous infusion. However, for long-term sedation, lorazepam is preferred due to its long duration of action, and propofol has advantages over midazolam when used in the ICU for sedation, such as shorter weaning time and earlier tracheal extubation.
Midazolam is a short-acting benzodiazepine central nervous system (CNS) depressant. Pharmacodynamic properties of midazolam and its metabolites, which are similar to those of other benzodiazepine drugs, include sedative, anxiolytic, amnestic, muscle relaxant, as well as hypnotic activities. Benzodiazepines enhance the inhibitory action of the amino acid neurotransmitter gamma-aminobutyric acid (GABA). Receptors for GABA are targeted by many important drugs that affect GABA function and are commonly used in the treatment of anxiety disorder, epilepsy, insomnia, spasticity, and aggressive behavior
Mechanism of action
The actions of benzodiazepines such as midazolam are mediated through the inhibitory neurotransmitter gamma-aminobutyric acid (GABA), which is one of the major inhibitory neurotransmitters in the central nervous system. Benzodiazepines increase the activity of GABA, thereby producing a sedating effect, relaxing skeletal muscles, and inducing sleep, anesthesia, and amnesia. Benzodiazepines bind to the benzodiazepine site on GABA-A receptors, which potentiates the effects of GABA by increasing the frequency of chloride channel opening. These receptors have been identified in different body tissues including the heart and skeletal muscle, although mainly appear to be present in the central nervous system.
Nausea, vomiting, dizziness, or drowsiness may occur. If any of these effects persist or worsen, notify the doctor or pharmacist promptly. Remember that the doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor right away if you have any serious side effects, including: mental/mood changes (e.g., agitation, aggressive behavior), uncontrollable movements (e.g., shaking/tremor), slow/fast heartbeat, vision changes (e.g., blurred vision). Get medical help right away if you have any very serious side effects, including: fainting, rapid/slow/shallow breathing.
Many drugs can interact with midazolam. Not all possible interactions are listed here. Tell your doctor about all your current medicines, especially: · antifungal medicine; · an antibiotic; · an antidepressant; · heart or blood pressure medicine; · antiviral medicine to treat hepatitis C or HIV/AIDS; · seizure medication; or · tuberculosis medication
This list is not complete and many other drugs can interact with midazolam. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Give a list of all your medicines to any healthcare provider who treats you.