Flumazenil adverse effects

Adverse effects of flumazenil include agitation, confusion, dizziness, and nausea. Flumazenil may cause a severe precipitated abstinence syndrome in patients who have developed physiologic benzodiazepine dependence. In patients who have ingested benzodiazepines with tricyclic antidepressants, seizures and cardiac arrhythmias may follow flumazenil administration. 

There was a variety of significant nervous system adverse effects in six of 104 patients who underwent transesophageal echocardiography, including aggression, euphoria, depression, and intense hiccups (42). These effects occurred despite careful titration and relatively low doses of intravenous midazolam (mean 4.8 mg), and were generally reversible with intravenous flumazenil 0.25-0.5 mg. 

Adverse effects of flumazenil can include brief anxiety, seizures in epileptics treated with a benzodiazepine and precipitation of withdrawal syndrome in dependent subjects. Rarely, vomiting is induced. 

Placebo-controHed studies In a doubleblind, randomized, placebo-controlled study in 105 unconscious adults with suspected drug overdose, 73 of whom had taken benzodiazepines, flumazenil caused adverse effects in nine cases agitation (n = 3), a depressive mood (n = 3), nausea and vomiting (n = 1), shivering (n = 1), and one severe adverse reaction—a sudden fall in blood pressure in a 28-year-old woman in deep coma after combined poisoning with benzodiazepines and maprotiline [95 "]. 

In a multicenter, double-blind, placebo-controlled study of the effects of intravenous flumazenil 0.7 mg in reversing the effects of midazolam, 82% of 131 flumazenil-treated patients had complete reversal of sedation, compared with 15% of 65 placebo-treated patients. However, flumazenil reversed midazolam-induced amnesia in only 60% of patients. Dizziness (10%) and nausea (9%) were the most common adverse effects [96 ]. Similar results were obtained in a double-blind, placebo-controlled study in patients who had been given midazolam plus an opioid (fentanyl, pethidine, or morphine) [97 ], intravenous diazepam [98 "], or diazepam plus an opioid [99 ]. 

In a single-dose, crossover, double-blind, placebo-controlled study of flumazenil and placebo in 16 subjects with Parkinson s disease, scores on the Unified Parkinson s Disease Rating Scale tended to improve, but the effect was not significant the most common adverse events were light-headedness or dizziness [92 ]. 

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