flurazepam (Dalmane)

Introduction

Tradename: Dalmane. DEA-controlled substance: class 4.

Indications

short-term management of insomnia

Contraindications

• pregnancy
• pre-existing CNS depression
• respiratory depression
• narrow-angle glaucoma

Caution:

• use with caution in patients receiving other CNS depressants
• safety in children not yet established

pregnancy category = x

safety in lactation = -

Dosage

15-30 mg PO QHS

Tabs: 15, 30 mg.

Pharmacokinetics

• prodrug for active metabolite desalkylflurazepam
• t1/2 of 74 +/- 24 hours for active metabolite

elimination via kidney

1/2life = 50-100 hours

protein binding = 96-98 %

elimination by hemodialysis = -

Adverse effects

• common (> 10%)
  • drowsiness, fatigue, impaired coordination, lightheadedness, memory impairment, insomnia, dysarthria, anxiety, decreased libido, depression, headache, dry mouth, constipation, decreased salivation, nausea/vomiting, diarrhea, tachycardia, chest pain, blurred vision, sweating, rash, increased or decreased appetite
• less common (1-10%)
  • confusion, nervousness, syncope, dizziness, akathisia, hypotension, rigidity, tremor, dermatitis, nasal congestion, weight gain or weight loss, increased salivation, hyperventilation, tinnitus, muscle cramps
• uncommon (< 1%)
  • muscle irregularities, blood dyscrasias, reflex slowing, dependence

• drug adverse effects of benzodiazepines
• drug adverse effects of psychotropic agents
• drug adverse effects of sedatives

Drug interactions

• additive effects with other CNS depressants
• carbamazepine may increase hepatic metabolism
• agents which decrease hepatic metabolism of flurazepam
  • cimetidine
  • estrogens
  • disulfiram
  • erythromycin

• drug interaction(s) of methadone in combination with benzodiazepines
• drug interaction(s) of benzodiazepines with antidepressants
• drug interaction(s) of benzodiazepines with thiazide diuretics
• drug interaction(s) of antipsycotics with benzodiazepines
• drug interaction(s) of antidepressants with benzodiazepines
• drug interaction(s) of beta-adrenergic receptor antagonists with benzodiazepines
• drug interaction(s) of beta-adrenergic receptor antagonists (except atenolol) with benzodiazepines
• drug interaction(s) of alcoholic beverage with benzodiazepines
• drug interaction(s) of benzodiazepine with opiates

Laboratory

• specimen: serum, plasma (EDTA)
• methods: GC, HPLC, RIA
• labs with Loincs
  • flurazepam in specimen
    • flurazepam in hair
    • flurazepam in tissue
    • flurazepam in body fluid
      • flurazepam in gastric fluid
      • flurazepam in stool
      • flurazepam in meconium
      • flurazepam in blood
      • flurazepam in serum/plasma
      • flurazepam in urine
      • flurazepam in vitreous fluid

Mechanism of action

benzodiazepine

More general terms

• benzodiazepine

More specific terms

• N-desalkylflurazepam

Database

• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=3393
• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=14434