Midazolam Hydrochloride

INDICATIONS AND USAGE Midazolam HCl 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. Midazolam HCl syrup is intended for use in monitored settings only and not for chronic or home use [see WARNINGS] .

DOSAGE AND ADMINISTRATION Midazolam HCl syrup is indicated for use as a single dose (0.25 to 1.0 mg/kg with a maximum dose of 20 mg) for preprocedural sedation and anxiolysis in pediatric patients. Midazolam HCl syrup is not intended for chronic administration. Monitoring Midazolam HCl syrup should only be used in hospital or ambulatory care settings, including physicians’ and dentists’ offices that can provide for continuous monitoring of respiratory and cardiac function. Immediate availability of resuscitative drugs and age- and size-appropriate equipment for bag/valve/mask ventilation and intubation, and personnel trained in their use and skilled in airway management should be assured [see WARNINGS] . For deeply sedated patients, a dedicated individual whose sole responsibility it is to observe the patient, other than the practitioner performing the procedure, should monitor the patient throughout the procedure. Continuous monitoring of respiratory and cardiac function is required. Midazolam HCl syrup must be given only to patients if they will be monitored by direct visual observation by a health care professional. Midazolam HCl syrup should only be administered by persons specifically trained in the use of anesthetic drugs and the management of respiratory effects of anesthetic drugs, including respiratory and cardiac resuscitation of patients in the age group being treated. Patient response to sedative agents, and resultant respiratory status, is variable. Regardless of the intended level of sedation or route of administration, sedation is a continuum; a patient may move easily from light to deep sedation, with potential loss of protective reflexes, particularly when coadministered with anesthetic agents, other CNS depressants, and concomitant medications which may potentially cause a more intense and prolonged sedation [see PRECAUTIONS: Drug Interactions] . This is especially true in pediatric patients. The health care practitioner who uses this medication in pediatric patients should be aware of and follow accepted professional guidelines for pediatric sedation appropriate to their situation. Sedation guidelines recommend a careful presedation history to determine how a patient’s underlying medical conditions or concomitant medications might affect their response to sedation/analgesia as well as a physical examination including a focused examination of the airway for abnormalities. Further recommendations include appropriate presedation fasting. Intravenous access is not thought to be necessary for all pediatric patients sedated for a diagnostic or therapeutic procedure because in some cases the difficulty of gaining IV access would defeat the purpose of sedating the child; rather, emphasis should be placed upon having the intravenous equipment available and a practitioner skilled in establishing vascular access in pediatric patients immediately available. Midazolam HCl syrup must never be used without individualization of dosage, particularly when used with other medications capable of producing CNS depression. Younger (<6 years of age) pediatric patients may require higher dosages (mg/kg) than older pediatric patients, and may require close monitoring. When midazolam HCl syrup is given in conjunction with opioids or other sedatives, the potential for respiratory depression, airway obstruction, or hypoventilation is increased. For appropriate patient monitoring, see WARNINGS and DOSAGE AND ADMINISTRATION: Monitoring. The health care practitioner who uses this medication in pediatric patients should be aware of and follow accepted professional guidelines for pediatric sedation appropriate to their situation. The recommended dose for pediatric patients is a single dose of 0.25 to 0.5 mg/kg, depending on the status of the patient and desired effect, up to a maximum dose of 20 mg. In general, it is recommended that the dose be individualized and modified based on patient age, level of anxiety, concomitant medications, and …

CONTRAINDICATIONS Midazolam HCl syrup is contraindicated in patients with a known hypersensitivity to the drug or allergies to cherries or formulation excipients. Benzodiazepines are contraindicated in patients with acute narrow-angle glaucoma. Benzodiazepines may be used in patients with open-angle glaucoma only if they are receiving appropriate therapy. Measurements of intraocular pressure in patients without eye disease show a moderate lowering following induction of general anesthesia with injectable midazolam; patients with glaucoma have not been studied.

ADVERSE REACTIONS The distribution of adverse events occurring in patients evaluated in a randomized, double-blind, parallel- group trial are presented in Tables 5 and 6 by body system in order of decreasing frequency: for the premedication period (eg, sedation period prior to induction of anesthesia) alone, see Table 5; for over the entire monitoring period including premedication, anesthesia and recovery, see Table 6. The distribution of adverse events occurring during the premedication period, before induction of anesthesia, is presented in Table 5. Emesis, which occurred in 31/397 (8%) patients over the entire monitoring period, occurred in 3/397 (0.8%) of patients during the premedication period (from midazolam administration to mask induction). Nausea, which occurred in 14/397 (4%) patients over the entire monitoring period (premedication, anesthesia and recovery), occurred in 2/397 (0.5%) patients during the premedication period. This distribution of all adverse events occurring in ≥1% of patients over the entire monitoring period are presented in Table 6. For the entire monitoring period (premedication, anesthesia and recovery), adverse events were reported by 82/397 (21%) patients who received midazolam overall. The most frequently reported adverse events were emesis occurring in 31/397 (8%) patients and nausea occurring in 14/397 (4%) patients. Most of these gastrointestinal events occurred after the administration of other anesthetic agents. For the respiratory system overall, adverse events (hypoxia, laryngospasm, rhonchi, coughing, respiratory depression, airway obstruction, upper-airway congestion, shallow respirations), occurred during the entire monitoring period in 31/397 (8%) patients and increased in frequency as dosage was increased: 7/132 (5%) patients in the 0.25 mg/kg dose group, 9/132 (7%) patients in the 0.5 mg/kg dose group, and 15/133 (11%) patients in the 1.0 mg/kg dose group. Most of the respiratory adverse events occurred during induction, general anesthesia or recovery. One patient (0.25%) experienced a respiratory system adverse event (laryngospasm) during the premedication period. This adverse event occurred precisely at the time of induction. Although many of the respiratory complications occurred in settings of upper airway procedures or concurrently administered opioids, a number of these events occurred outside of these settings as well. In this study, administration of midazolam HCl syrup was generally accompanied by a slight decrease in both systolic and diastolic blood pressures, as well as a slight increase in heart rate. Table 5: Adverse Events Occurring During the Premedication Period Before Mask Induction in the Randomized, Double-Blind, Parallel-Group Trial Body System Treatment Regimen Overall No. Patients with Adverse Events 0.25 mg/kg (n=132) 0.50 mg/kg (n=132) 1.0 mg/kg (n=133) (n=397) No. (%) No. (%) No. (%) No. (%) Gastrointestinal System Disorders Emesis 1 (0.76%) 1 (0.76%) 1 (0.75%) 3 (0.76%) Nausea 2 (1.5%) 2 (0.50%) Respiratory System Disorders Laryngospasm 1* (0.75%) 1 (0.25%) Sneezing/Rhinorrhea 1 (0.75%) 1 (0.25%) ALL BODY SYSTEMS 1 (0.76%) 1 (0.76%) 5 (3.8%) 7 (1.8%) *This adverse event occurred precisely at the time of induction. Table 6: Adverse Events (≥1%) From the Randomized, Double-Blind, Parallel-Group Trial on Entire Monitoring Period (premedication, anesthesia, recovery) Body System Treatment Regimen Overall No. Patients with Adverse Events 0.25 mg/kg (n=132) 0.50 mg/kg (n=132) 1.0 mg/kg (n=133) (n=397) No. (%) No. (%) No. (%) No. (%) Gastrointestinal System Disorders Emesis 11 (8%) 5 (4%) 15 (11%) 31 (8%) Nausea 6 (5%) 2 (2%) 6 (5%) 14 (4%) Overall 16 (12%) 8 (6%) 16 (12%) 40 (10%) Respiratory System Disorders Hypoxia 0 5 (4%) 4 (3%) 9 (2%) Laryngospasm 0 1 (<1%) 5 (4%) 6 (2%) Respiratory Depression 2 (2%) 1 (<1%) 2 (2%) 5 (1%) Rhonchi 2 (2%) 1 (<1%) 2 (2%) 5 (1%) Airway Obstruction 2 (2%) 2 (2%) 0 4 (1%) Upper Airway Congestion 2 (2%) 0 2 (2%) 4 (1%) Overall …

Drug Interactions Effect of Concomitant Use of Benzodiazepines and Opioids The concomitant use of benzodiazepines and opioids increases the risk of respiratory depression because of actions at different receptor sites in the CNS that control respiration. Benzodiazepines interact at GABA A sites, and opioids interact primarily at mu receptors. When benzodiazepines and opioids are combined, the potential for benzodiazepines to significantly worsen opioid-related respiratory depression exists. Monitor patients closely for respiratory depression and sedation. Other CNS Depressants One case was reported of inadequate sedation with chloral hydrate and later with oral midazolam due to a possible interaction with methylphenidate administered chronically in a 2-year-old boy with a history of Williams syndrome. The difficulty in achieving adequate sedation may have been the result of decreased absorption of the sedatives due to both the gastrointestinal effects and stimulant effects of methylphenidate. The sedative effect of midazolam HCl syrup is accentuated by any concomitantly administered medication which depresses the central nervous system, particularly opioids (e.g., morphine, meperidine, and fentanyl), propofol, ketamine, nitrous oxide, secobarbital and droperidol. Consequently, the dose of midazolam HCl syrup should be adjusted according to the type and amount of concomitant medications administered and the desired clinical response [see DOSAGE AND ADMINISTRATION] . No significant adverse interactions with common premedications (such as atropine, scopolamine, glycopyrrolate, diazepam, hydroxyzine, and other muscle relaxants) or local anesthetics have been observed. Inhibitors of CYP3A4 Isozymes Caution is advised when midazolam is administered concomitantly with drugs that are known to inhibit the cytochrome P450 3A4 enzyme system (ie, some drugs in the drug classes of azole antimycotics, protease inhibitors, calcium channel antagonists, and macrolide antibiotics). Drugs such as diltiazem, erythromycin, fluconazole, itraconazole, ketoconazole, saquinavir, and verapamil were shown to significantly increase the C max and AUC of orally administered midazolam. These drug interactions may result in increased and prolonged sedation due to a decrease in plasma clearance of midazolam. Although not studied, the potent cytochrome P450 3A4 inhibitors ritonavir and nelfinavir may cause intense and prolonged sedation and respiratory depression due to a decrease in plasma clearance of midazolam. Caution is advised when midazolam HCl syrup is used concomitantly with these drugs. Dose adjustments should be considered and possible prolongation and intensity of effect should be anticipated [see CLINICAL PHARMACOLOGY: Pharmacokinetics: Special Populations: Drug-Drug Interactions] . Inducers of CYP3A4 Isozymes Cytochrome P450 inducers, such as rifampin, carbamazepine, and phenytoin, induce metabolism and cause a markedly decreased C max and AUC of oral midazolam in adult studies. Although clinical studies have not been performed, phenobarbital is expected to have the same effect. Caution is advised when administering midazolam HCl syrup to patients receiving these medications and if necessary dose adjustments should be considered.

DESCRIPTION Midazolam is a benzodiazepine available as midazolam HCl syrup for oral administration. Midazolam, a white to light yellow crystalline compound, is insoluble in water, but can be solubilized in aqueous solutions by formation of the hydrochloride salt in situ under acidic conditions. Chemically, midazolam HCl is 8-chloro-6-(2-fluorophenyl)-1-methyl-4 H -imidazo[1,5-a][1,4]benzodiazepine hydrochloride. Midazolam hydrochloride has the molecular formula C 18 H 13 ClFN 3 ·HCl, a calculated molecular weight of 362.25 and the following structural formula: Each mL of the syrup contains midazolam hydrochloride equivalent to 2 mg midazolam compounded with bitterness modifier, artificial cherry-brandy flavor, citric acid anhydrous, D&C Red #33, edetate disodium, glycerin, sodium benzoate, sodium citrate, sodium saccharin, sorbitol solution, and water; the pH is adjusted to 2.8 to 3.6 with hydrochloric acid. Under the acidic conditions required to solubilize midazolam in the syrup, midazolam is present as an equilibrium mixture (shown below) of the closed ring form shown above and an open-ring structure formed by the acid-catalyzed ring opening of the 4,5-double bond of the diazepine ring. The amount of open-ring form is dependent upon the pH of the solution. At the specified pH of the syrup, the solution may contain up to about 40% of the open-ring compound. At the physiologic conditions under which the product is absorbed (pH of 5 to 8) into the systemic circulation, any open-ring form present reverts to the physiologically active, lipophilic, closed-ring form (midazolam) and is absorbed as such. Midazolam Open-ring Form The following chart below plots the percentage of midazolam present as the open-ring form as a function of pH in aqueous solutions. As indicated in the graph, the amount of open-ring compound present in solution is sensitive to changes in pH over the pH range specified for the product: 2.8 to 3.6. Above pH 5, at least 99% of the mixture is present in the closed-ring form. midazolam1-chem.jpg midazolam2-black.jpg midazolam-hydroch-04.jpg

OVERDOSAGE Clinical Presentation Overdosage of benzodiazepines is characterized by central nervous system depression ranging from drowsiness to coma. In mild to moderate cases, symptoms can include drowsiness, confusion, dysarthria, lethargy, hypnotic state, diminished reflexes, ataxia, and hypotonia. Rarely, paradoxical or disinhibitory reactions (including agitation, irritability, impulsivity, violent behavior, confusion, restlessness, excitement, and talkativeness) may occur. In severe overdosage cases, patients may develop respiratory depression and coma. Overdosage of benzodiazepines in combination with other CNS depressants (including alcohol and opioids) may be fatal [see WARNINGS: Dependence and Withdrawal Reactions ] . Markedly abnormal (lowered or elevated) blood pressure, heart rate, or respiratory rate raise the concern that additional drugs and/or alcohol are involved in the overdosage. Management of Overdose In managing benzodiazepine overdosage, employ general supportive measures, including intravenous fluids and airway management. Flumazenil, a specific benzodiazepine receptor antagonist, is indicated for the complete or partial reversal of the sedative effects of benzodiazepines in the management of benzodiazepine overdosage, can lead to withdrawal and adverse reactions, including seizures, particularly in the context of mixed overdosage with drugs that increase seizure risk (e.g., tricyclic and tetracyclic antidepressants) and in patients with long term benzodiazepine use and physical dependency. The risk of withdrawal seizures with flumazenil use may be increased in patients with epilepsy. Flumazenil is contraindicated in patients who have received a benzodiazepine for control of a potentially life-threatening condition (e.g., status epilepticus). If the decision is made to use flumazenil, it should be used as an adjunct to, not as a substitute for, supportive management of benzodiazepine overdosage. See the flumazenil injection Prescribing Information. Consider contacting a poison center (1-800-222-1222), poisoncontrol.org , or a medical toxicologist for additional overdosage management recommendations.

HOW SUPPLIED Midazolam HCl Syrup is supplied as a clear, red to purplish-red, mixed fruit flavored syrup containing midazolam hydrochloride equivalent to 2 mg of midazolam/mL; each amber glass bottle of 118 mL of syrup is supplied with 1 press-in bottle adapter, 4 single-use, graduated, oral dispensers and 4 tip caps; 10 x bottle of 2.5 mL is supplied with 10 single-use, graduated, oral dispensers and 10 tip caps. NDC 0574-0150-04 Bottle of 118 mL. NDC 0574-0150-25 10 x Bottle of 2.5 mL. Store at 20° to 25°C (68° to 77°F). [See USP Controlled Room Temperature.]