Trade Names:Klonopin- Tablets 0.5 mg- Tablets 1 mg- Tablets 2 mg- Tablets, orally disintegrating 0.125 mg- Tablets, orally disintegrating 0.25 mg- Tablets, orally disintegrating 0.5 mg- Tablets, orally disintegrating 1 mg- Tablets, orally disintegrating 2 mgApo-Clonazepam (Canada)CO Clonazepam (Canada)Gen-Clonazepam (Canada)PMS-Clonazepam (Canada)ratio-Clonazepam (Canada)Rivotril (Canada)Sandoz Clonazepam (Canada)
Potentiates action of GABA, inhibitory neurotransmitter, resulting in increased neuronal inhibition and CNS depression, especially in limbic system and reticular formation.
Rapidly absorbed. About 90% bioavailable. T max is 1 to 4 h.
About 85% protein bound.
Highly metabolized in the liver; CYP-450, including CYP3A4, may play a major role in oxidation and reduction of clonazepam.
The t ½ is 30 to 40 h. Less than 2% is excreted in urine as unchanged drug.
Treatment of Lennox-Gastaut syndrome; management of akinetic and myoclonic seizures and absence seizures unresponsive to succinimides; panic disorders.
Treatment of restless legs syndrome, parkinsonian dysarthria, acute manic episodes of bipolar affective disorder, multifocal tic disorders and neuralgias; adjunctive therapy for schizophrenia.
Hypersensitivity to benzodiazepines; psychoses; acute narrow-angle glaucoma; significant liver disease; shock; coma; acute alcohol intoxication.
PO Start with 0.25 mg twice daily. An increase to the target dose for most patients of 1 mg/day may be made after 3 days. Dose may be increased in increments of 0.125 to 0.25 mg twice daily every 3 days until panic disorder is controlled or side effects make further undesired increases (max, 4 mg/day).Seizure DisordersAdults Initial dose
PO 1.5 mg/day in 3 divided doses. Increase by 0.5 to 1 mg every 3 days until seizures are adequately controlled (max, 20 mg/day).Infants and Children (10 yr of age or younger; 30 kg or less) Initial dose
PO 0.01 to 0.03 mg/kg/day in 2 to 3 divided doses. Increase by 0.25 to 0.5 mg every 3 days until maintenance dose of 0.1 to 0.2 mg/kg has been reached.
Store at controlled room temperature (59° to 86°F).
May cause additive CNS depressant effects.Carbamazepine, phenytoin, rifampin
May reduce clonazepam serum concentrations, decreasing the clinical effect.Cimetidine, disulfiram, oral contraceptives
May cause effects of clonazepam to increase, with excessive sedation and impaired psychomotor function.Digoxin
May increase serum digoxin concentrations.Theophyllines
May antagonize sedative effects.
None well documented.
CV collapse; hypotension; phlebitis or thrombosis at IV sites.
Somnolence (50%); dizziness (12%); abnormal coordination (9%); ataxia, depression (8%); memory disturbance (5%); nervousness, reduced intellectual ability, dysarthria (4%); decreased libido (3%); emotional lability, confusion (2%).Seizure disorders
Drowsiness (50%); ataxia (30%); confusion; dizziness; lethargy; fatigue; apathy; memory impairment; disorientation; anterograde amnesia; restlessness; headache; slurred speech; aphonia; stupor; coma; euphoria; irritability; vivid dreams; psychomotor retardation; paradoxic reactions (eg, anger, hostility, mania, insomnia, muscle spasms).
Pharyngitis, blurred vision (3%).Seizure disorders
Visual and auditory disturbances; depressed hearing.
Constipation (5%); decreased appetite (3%); abdominal pain (2%).Seizure disorders
Constipation; diarrhea; dry mouth; coated tongue; excessive salivation; nausea; anorexia; vomiting.
Dysmenorrhea (6% [women]); colpitis (4% [women]); impotence (men); micturition frequency, delayed ejaculation (2% [men]), UTI (2%).Seizure disorders
Dysuria; enuresis; nocturia; urinary retention.
Blood dyscrasias including agranulocytosis; anemia; thrombocytopenia; leukopenia; neutropenia.
Hepatic dysfunction, including hepatitis and jaundice; elevated LDH, ALT, AST, and alkaline phosphatase.
Upper respiratory tract infection (10%); sinusitis (8%); rhinitis, coughing (4%); bronchitis (2%).
Fatigue (9%); influenza (5%); allergic reaction, myalgia (4%).Seizure disorders
Dependence/withdrawal syndrome (eg, confusion, abnormal perception of movement, depersonalization, muscle twitching, psychosis, paranoid delusions, seizures).
Ensure that CBC with differential and liver enzymes are evaluated periodically in patient on prolonged therapy.Response to treatment
Frequently assess patient for response to treatment. Notify health care provider if condition does not appear to improve or worsens.Review therapy
Ensure that therapy is periodically reviewed to determine if it needs to be continued without change or if a dose change (eg, increase, decrease, discontinuation) is indicated.
Category D .
Excreted in breast milk.
Safety and efficacy not established.Seizure disorders
Initial dose should be small and gradually increased. Long-term use may cause adverse effects such as possibly delayed mental or physical development.
Use drug with caution to avoid accumulation.
Use drug with caution to avoid accumulation.
Withdrawal symptoms of the barbiturate type may occur.
Initial dose should be small and gradually increased. Give drug with extreme care to elderly or very ill patients with limited respiratory reserve.
Because an increase in salivation may occur, use with caution in patients who have difficulty handling secretions or those with chronic respiratory disease.
Not intended for use in patients with primary depressive disorder, psychosis, or disorders in which anxiety is not prominent.
In patients with multiple seizure types, drug may increase incidence or precipitate onset of grand mal seizures.
Use drug with caution in patients with suicidal tendencies; do not allow patient access to large quantities.
Abrupt discontinuation, particularly in patients on long-term, high-dose therapy, may precipitate status epilepticus. If treatment is to be discontinued or the dose reduced, gradually taper the dose and monitor patient for withdrawal symptoms. If significant withdrawal symptoms develop (eg, increased anxiety, tremor, muscle or abdominal cramps, sweating), reinstitute previous dosing schedule and attempt a less rapid tapering regimen after patient has stabilized.
Somnolence, confusion, diminished reflexes, coma.
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