Midazolam

It is an ultra-short benzodiazepine having the benefit of rapid onset of action, recovery, and nonpainful induction and lack of venous irritation.

Indications

Preoperative sedation/anxiolysis. Induction of general anaesthesia. Sedative/hypnotic for gastro-intestinal endoscopy, bronchoscopy, dentistry and surgery done under regional anaesthesia. In ICU for artificial ventilation which requires long-term sedation.

Dosage

Standard i.m. dose is 0.07 to 0.08 mg/kg, i.e. 3-6 mg of midazolam. The standard i.v. dose is 0.01 to 0.07 mg/kg i.e. 2.5mg of midazolam. For induction of general anaesthesia, the recommended dose is 0.1 to 0.5 mg/kg is the incremental dose subsequent to an initial dose of 0.08 mg/kg.

Contra-Indications

Hypersensitivity. Patients with acute narrow-angle glaucoma. Intrathecal or epidural administration. Adults or paediatric patients in shock or coma, or in acute alcohol intoxication with depression of vital signs. Respiratory disease.

Special Precautions

Titrate slowly in adult or paediatric patients when indicated for sedation/anxiolysis/amnesia. Do not discontinue abruptly after a long-term administration. Less frequent or lower doses should be instituted in higher risk adult and paediatric surgical patients, elderly, debilitated patients, patients with COPD, patients with chronic renal failure and CHF, patients with uncompensated acute illness, such as severe fluid or electrolyte disturbances. Pregnancy : Use only, if the potential benefits

Side Effects

Decreased tidal volume, respiratory rate decrease, apnea, and variations in blood pressure and pulse rate. In adults, on IM administration, headache, local effects and on IV administration, hiccoughs, nausea, vomiting, coughing, oversedation, headache, drowsiness local effects are observed. In paediatrics, on IV administration desaturation, apnea, hypertension, paradoxical reactions, kernicterus, hiccoughs, seizure-like activity and nystagmus are observed.

Drug Interactions

A decrease in plasma clearance leading to prolonged sedation when used with inhibitors of cytochrome P450-3A4 enzyme. Decrease in MAC of halothane. On rapid injection of either midazolam or fentanyl in neonates who are on either infusion of fentanyl or midazolam, respectively, result in severe hypotension.