Page 408 - Basic _ Clinical Pharmacology ( PDFDrive )

394 SECTION V Drugs That Act in the Central Nervous System

Mechanism of Pharmacokinetics,
Subclass, Drug Action Effects Clinical Applications Toxicities, Interactions
NEWER HYPNOTICS
• Eszopiclone Bind selectively to a Rapid onset of hypnosis with Sleep disorders, especially Oral activity • short half-lives • CYP substrates
• Zaleplon subgroup of GABA A few amnestic effects or day- those characterized by • Toxicity: Extensions of CNS depressant
• Zolpidem receptors, acting like after psychomotor difficulty in falling asleep effects • dependence liability
benzodiazepines to depression or somnolence • Interactions: Additive CNS depression with
enhance membrane ethanol and many other drugs
hyperpolarization
MELATONIN RECEPTOR AGONISTS
• Ramelteon Activates MT 1 and MT 2 Rapid onset of sleep with Sleep disorders, especially Oral activity • forms active metabolite via
receptors in minimal rebound insomnia or those characterized by CYP1A2 • Toxicity: Dizziness • fatigue
suprachiasmatic nuclei withdrawal symptoms difficulty in falling asleep • endocrine changes • Interactions:
in the CNS • not a controlled substance Fluvoxamine inhibits metabolism
• Tasimelteon: Orally active MT 1 and MT 2 agonist, recently approved for non-24-hour sleep disorder

OREXIN ANTAGONIST
• Suvorexant Blocks binding of Promotes sleep onset and Sleep disorders, especially CYP450 metabolism is inhibited by
orexins, duration those characterized by fluconazole, verapamil, and grapefruit juice
neuropeptides that difficulty in falling asleep • next-day somnolence and driving
promote wakefulness impairment

5-HT-RECEPTOR AGONIST
• Buspirone Mechanism uncertain: Slow onset (1–2 weeks) of Generalized anxiety states Oral activity • forms active metabolite • short
Partial agonist at 5-HT anxiolytic effects • minimal half-life • Toxicity: Tachycardia • paresthesias
receptors but affinity psychomotor impairment— • gastrointestinal distress • Interactions:
for D 2 receptors also no additive CNS depression CYP3A4 inducers and inhibitors
possible with sedative-hypnotic drugs

PREP AR A TIONS A V AIL ABLE

GENERIC NAME AVAILABLE AS GENERIC NAME AVAILABLE AS
BENZODIAZEPINES Pentobarbital Generic, Nembutal Sodium
Alprazolam Generic, Xanax Phenobarbital Generic, Luminal Sodium
Chlordiazepoxide Generic, Librium Secobarbital Generic, Seconal
Clonazepam Generic, Tranxene MISCELLANEOUS
Clorazepate Generic, Klonopin DRUGS
Diazepam Generic, Valium Buspirone Generic, BuSpar
Estazolam Generic, ProSom Chloral hydrate Generic, Aquachloral
Flurazepam Generic, Dalmane Supprettes
Lorazepam Generic, Ativan Eszopiclone Lunesta
Midazolam Generic, Versed Hydroxyzine Generic, Atarax,
Vistaril
Oxazepam Generic, Serax Meprobamate Generic, Equanil,
Quazepam Generic, Doral Miltown
Temazepam Generic, Restoril Paraldehyde Generic
Triazolam Generic, Halcion Ramelteon Rozerem
BENZODIAZEPINE ANTAGONIST Suvorexant Belsomra
Flumazenil Generic, Romazicon Tasimelteon Hetlioz
BARBITURATES Zaleplon Sonata
Amobarbital Amytal Zolpidem Generic, Ambien,
Mephobarbital Mebaral (withdrawn) Ambien-CR