Chapter 13 CNS Depressants and muscle relaxants

Question 1

Anxiolytic

Answer 1

A medication that relieves anxiety

Question 2

Barbiturates

Answer 2

A class of drugs that are chemical derivatives of barbituric acid. They can induce sedation and sleep. Can also be used as an anticonvulsant.

• They are not used as frequently as they used to be because they have a very narrow therapeutic window (more chance for adverse side effects).
• Four categories: ultra-short, short, intermediate, and long. Most used in the OR.
• ends in “tal” often
• Potentiates GABA and inhibit nerve impulses
• Adverse effects include drowsiness, lethargy, vertigo, respiratory depression, cough, apnea, nausea, vomiting, diarrhea, hypotension

Question 3

Benzodiazepines

Answer 3

A chemical category of drugs most frequently prescribed as sedative-hypnotic and anxiolytic drugs. The most common group of psychotropic drugs currently prescribed to alleviate anxiety.

• suffix ends in “pam”
• Depresses the CNS activity, does not suppress REM sleep as much as barbiturates, does not increase metabolism of other drugs
• Adverse effects include headache, drowsiness, dizziness, vertigo, lethargy, fall hazard, hangover effect
• Grapefruit interacts
• Avoid alcohol and other CNS depressants

Question 4

Gamma-aminobutyric acid (GABA)

Answer 4

An inhibitory neurotransmitter found in the brain that functions in inhibit nerve transmission in the CNS

Question 5

Hypnotics

Answer 5

Drugs that, when given at low to moderate doses, calm or soothe the CNS without inducing sleep but when given at high doses may cause sleep

Question 6

Non-rapid eye movement (non REM) sleep

Answer 6

One of the stages of the sleep cycle. It characteristically has four stages and precedes REM sleep. Most of a normal sleep cycle consists of non REM sleep

Question 7

Rapid eye movement (REM) sleep

Answer 7

One of the stages of the sleep cycle. Some of the characteristics of REM sleep are rapid movement of the eyes, vivid dreams, and irregular breathing

Question 8

REM interference

Answer 8

A drug-induced reduction of REM sleep time

Question 9

REM rebound

Answer 9

Excessive REM sleep following discontinuation of sleep-altering drugs

Question 10

Sedatives

Answer 10

Drugs that have an inhibitory effect on the CNS to the degree that they reduce nervousness, excitability, and irritability without causing sleep
- A sedative can become a hypnotic if given a large doses

Question 11

Sedative-hypnotics

Answer 11

Drugs that can act in the body either as sedatives or hypnotics depending on the dosage.

• At low doses, they calm the CNS without inducing sleep
• At high doses, they calm the CNS to the point of causing sleep
• Barbituates and benzodiazepines

Question 12

Sleep

Answer 12

A transient, reversible, and periodic state of rest in which there is a decrease in physical activity and consciousness
- Includes REM and non REM

Question 13

Sleep architecture

Answer 13

The structure of the elements involved in the sleep cycle, including normal and abnormal patterns of sleep

Question 14

Tachyphylaxis

Answer 14

The rapid appearance of a progressive decrease in response to a drug after repetitive administration of the drug

Question 15

Therapeutic index

Answer 15

The ratio between the toxic and therapeutic concentrations of a drug. If the index is low, the difference between the therapeutic and toxic drug concentration is small, and use of the drug is more hazardous