II. Class

  1. Long acting Benzodiazepine

III. Indications

  1. Anxiety Disorder
  2. Tic Disorder or Tourette's Syndrome
  3. Seizure Disorder
    1. Lennox-Gastaut Syndrome
    2. Akinetic Seizure
    3. Myoclonic Seizure

IV. Contraindications

  1. Hepatic Failure
  2. Narrow Angle Glaucoma

V. Dosing: Adults

  1. Panic Disorder or Generalized Anxiety Disorder
    1. Start 0.25 orally twice daily
    2. Titrate: Increase by 0.125 to 0.25 every 3 days to typical target dose of 1 mg/day divided
    3. Maximum Daily Dose: 4 mg (1.5 mg/day in elderly)
      1. No evidence of benefit for total daily dose above 1 to 2 mg
  2. Akinetic or Myoclonic Seizures or Lennox-Gestaut Syndrome (type of Petit Mal Seizures)
    1. Start 0.5 mg orally three times daily
    2. May increase dose by 0.5 to 1 mg orally every 3 days as needed to typical 2 to 8 mg/day in divided doses
    3. Maximum: 20 mg/day
  3. REM Sleep Behavior Disorder (Not FDA approved)
    1. Dose 1 to 2 mg orally at bedtime

VI. Dosing: Children (age <10 years or weight <30 kg)

  1. Akinetic or Myoclonic Seizures or Lennox-Gestaut Syndrome (type of Petit Mal Seizures)
    1. Start 0.01 to 0.03 mg/kg/day orally divided 2 to 3 times daily
    2. May increase dose by 0.25 to 0.5 mg orally every 3 days as needed
    3. Maximum: 0.1 to 0.2 mg/day divided 2 to 3 times daily

VII. Dosing: Equivalent Dosing (for Benzodiazepine Withdrawal)

  1. Valium = Clonazepam Dose x2.5
  2. Phenobarbital = Clonazepam Dose x7.5

VIII. Pharmacokinetics

  1. Half Life: 20-48 hours (up to 60 hours)
  2. Therapeutic Range: 20 to 80 ng/ml
  3. Rapidly and completely absorbed PO
  4. Metabolized via CYP3A4 to inactive metabolites

IX. Safety

  1. Pregnancy Category D (esp. avoid in first trimester)
  2. Avoid in Lactation
  3. Schedule IV Controlled Substance

X. Adverse Effects

  1. Sedation
  2. Weight gain
  3. Impaired academic performance
  4. Social anxiety with School Refusal in children
  5. Worsening of attention in children with ADHD
  6. Hypersalivation

XII. References

  1. (2019) Med Lett Drugs Ther 61(1578): 121-6
  2. (2020) Presc Lett, Resource #361206, Appropriate Use of Benzodiazepines
  3. Olson (2020) Clinical Pharmacology, Medmaster Miami, p. 55
  4. Hamilton (2020) Tarascon Pocket Pharmacopoeia

Images: Related links to external sites (from Bing)

Related Studies

Cost: Medications

clonazepam (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing)
CLONAZEPAM 0.125 MG DIS TAB Generic $0.57 each
CLONAZEPAM 0.125 MG ODT Generic $0.53 each
CLONAZEPAM 0.25 MG ODT Generic $0.56 each
CLONAZEPAM 0.5 MG DIS TABLET Generic $0.54 each
CLONAZEPAM 0.5 MG ODT Generic $0.49 each
CLONAZEPAM 0.5 MG TABLET Generic $0.03 each
CLONAZEPAM 1 MG DIS TABLET Generic $0.62 each
CLONAZEPAM 1 MG ODT Generic $0.42 each
CLONAZEPAM 1 MG TABLET Generic $0.03 each
CLONAZEPAM 2 MG ODT Generic $1.25 each
CLONAZEPAM 2 MG TABLET Generic $0.03 each
klonopin (on 4/20/2022 at Medicaid.Gov Survey of pharmacy drug pricing)
KLONOPIN 0.5 MG TABLET Generic $0.03 each
KLONOPIN 1 MG TABLET Generic $0.03 each

Ontology: Clonazepam (C0009011)

Definition (CHV) a kind of anti-anxiety drug also used to treat sleep disorders
Definition (NCI) A synthetic benzodiazepine derivative used for myotonic or atonic seizures, absence seizures, and photosensitive epilepsy, anticonvulsant Clonazepam appears to enhance gamma-aminobutyric acid receptor responses, although its mechanism of action is not clearly understood. It is seldom effective in generalized tonic-clonic or partial seizures. (NCI04)
Definition (MSH) An anticonvulsant used for several types of seizures, including myotonic or atonic seizures, photosensitive epilepsy, and absence seizures, although tolerance may develop. It is seldom effective in generalized tonic-clonic or partial seizures. The mechanism of action appears to involve the enhancement of GAMMA-AMINOBUTYRIC ACID receptor responses.
Definition (CSP) 5-(o-chlorophenyl)-1,3-dihydro -7-nitro-2H-1,4-benzodiazepin-2-one; anticonvulsant used against epileptic seizures and tardive dyskinesia.
Concepts Pharmacologic Substance (T121) , Organic Chemical (T109)
MSH D002998
SnomedCT 323076001, 322892002, 387383007, 69708003
LNC LP16086-8, MTHU004253
English Clonazepam, 2H-1,4-Benzodiazepin-2-one, 5-(2-chlorophenyl)-1,3-dihydro-7-nitro-, Clonazepam [epilepsy control], Clonazepam [status epilepsy], clonazepam, clonazepam (medication), CLONAZEPAM, Clonazepam [Chemical/Ingredient], clonazePAM, ClonazePAM, Clonazepam [status epilepsy] (product), Clonazepam [epilepsy control] (product), Clonazepam (product), Clonazepam (substance), Clonazepam [epilepsy control] (substance), Clonazepam [status epilepsy] (substance)
Swedish Klonazepam
Czech klonazepam
Finnish Klonatsepaami
Russian ANTELEPSIN, KLONAZEPAM, АНТЭЛЕПСИН, КЛОНАЗЕПАМ
Japanese クロナゼパム, リボトリール
Spanish clonazepam (producto), clonacepam (producto), clonacepam, clonazepam [antiepiléptico] (producto), clonazepam [estado epiléptico] (producto), clonazepam [antiepiléptico], clonazepam [estado epiléptico], clonacepam (sustancia), clonazepam (sustancia), clonazepam, Clonazepam
Polish Klonazepam
French Clonazépam
German Clonazepam
Italian Clonazepam
Portuguese Clonazepam

Ontology: Klonopin (C0699315)

Concepts Pharmacologic Substance (T121) , Organic Chemical (T109)
English Klonopin, klonopin, KlonoPIN