Sedative-Hypnotic Drugs Chapter 22

Questions and Answers

What effect does rifampin have on ramelteon and its active metabolite?

Markedly reduces plasma levels (correct)

Has no effect on plasma levels

Increases plasma levels significantly

Alters the half-life of ramelteon

Why are benzodiazepines preferred over barbiturates for treating anxiety?

They have a lower risk of addiction

They are more effective for everyday stress

They provide better long-term relief

They have a higher therapeutic index (correct)

In which scenario should ramelteon be used with caution?

In patients with diabetes

In elderly patients

In patients with renal impairment

In patients with liver dysfunction (correct)

Which of the following is NOT a common adverse drug reaction (ADR) associated with ramelteon?

Nausea Signup and view all the answers

What is one advantage of using flumazenil in benzodiazepine overdose?

It allows rapid restoration of consciousness Signup and view all the answers

Which benzodiazepine is noted for greater efficacy in long-term treatment of panic disorders?

Alprazolam Signup and view all the answers

What is a characteristic of the antianxiety effects of benzodiazepines compared to hypnotic effects?

They are less subject to tolerance Signup and view all the answers

Which clinical use is NOT appropriate for benzodiazepines?

Management of everyday stress Signup and view all the answers

How does the half-life of the active metabolite of ramelteon compare to the parent drug?

It is longer Signup and view all the answers

What is one reason benzodiazepines replaced barbiturates in anxiety treatment?

Benzodiazepines have fewer drug interactions Signup and view all the answers

Study Notes

Introduction to Sedative-Hypnotic Drugs

Sedative drugs (anxiolytics) alleviate anxiety and promote calmness.
Hypnotic drugs induce drowsiness, assisting with sleep onset and maintenance.
Increased doses lead to more pronounced central nervous system (CNS) depression.

Types of Sedative-Hypnotics

Major drug categories include:
- Benzodiazepines: Serve as anxiolytics and hypnotics.
- Barbiturates: Limited to anesthesia and epilepsy management.
- Miscellaneous agents.

β-blockers (e.g., Propranolol).
Antipsychotics and antidepressants (including SSRIs, TCAs, venlafaxine, duloxetine, MAOIs).
Antihistamines:
- Agonists include benzodiazepines, Zolpidem, zaleplon, and eszopiclone (selective at BZ1 site).
- Antagonist: Flumazenil (blocks benzodiazepines but not barbiturates).
- Inverse agonists can induce anxiety and seizures.

Pharmacokinetics of Benzodiazepines

Benzodiazepines vary in duration of action: long, intermediate, and short-acting.
Absorption: Lipid-soluble benzodiazepines penetrate the CNS rapidly.
Distribution: Crosses the placental barrier; can affect neonates if administered pre-delivery.
Metabolism: Biotransformation to water-soluble metabolites via phase 1 and 2 reactions.

Effects of Benzodiazepines

Long-acting agents may convert to active metabolites with prolonged effects.
Muscle relaxation and CNS depression can occur, particularly at high doses.
Anterograde amnesia prevents memory formation while under influence.

Classification of Barbiturates

Generalized CNS inhibition with significant respiratory and cardiovascular effects at therapeutic doses.
Respiratory depression common, particularly fatal in overdoses; caution in patients with pulmonary issues.

Unwanted Effects of Benzodiazepines

Tolerance: Reduced responsiveness leading to increased dosage for effect.
Dependence: Risk of withdrawal symptoms after prolonged use; symptoms include rebound insomnia, anxiety, and CNS excitability.
Adverse effects: Include drowsiness, impaired judgment, and diminishing motor skills; impacts driving and relationships.

Toxic Effects and Overdoses

Barbiturate overdoses lead to severe respiratory and cardiovascular depression.
Benzodiazepine overdoses are less likely to be fatal but still pose risks, especially in vulnerable populations.

Rationale for Clinical Use of Benzodiazepines

Preferred for anxiety management over barbiturates due to:
- Rapid onset.
- Higher therapeutic index.
- Flumazenil availability for overdose treatment.
- Lower risk of drug interactions and minimal effects on cardiovascular/ autonomic systems.

Treatment Guidelines

Alprazolam and clonazepam show greater efficacy in managing anxiety and phobias long-term.
Benzodiazepines should be employed for severe anxiety only, with caution due to addiction potential; recommended for short durations.
Antianxiety effects less prone to tolerance compared to hypnotic effects.

Description

This quiz focuses on Chapter 22, which explores sedative-hypnotic drugs, including their effects as anxiolytics and hypnotics. Understand the relationship between normal CNS activity and sedation or hypnosis. Test your knowledge of these essential pharmacological agents.