CNS Depressants

Question 1

Hypnotics

Answer 1

Reduce CNS function to the point that they cause sleep

A sedative can become a hypnotic if given in large enough doses

Question 2

Sedative-Hypnotics

Answer 2

Low dose: depress CNS function without inducing sleep

Higher dose: depress CNS function to the point of causing sleep

Question 3

Barbiturates

Answer 3

Habit forming - addictive.

Benzodiazepines preferred.

Indications: Anti-epileptic, anaesthesia

DRUGS:
Long acting: Phenobarbital (epilepsy)

Short acting: PenTObarbital (rarely used)

Question 4

Barbiturates drug effects/interactions/adverse

Answer 4

Increase liver enzymes that metabolize many drugs. (decreased anticoagulant effects of warfarin)

Additive effects (other CNS depressants)

ADVERSE: resp depression, drowsiness

Question 5

Benzodiazepines

Answer 5

Most frequently prescribed sedative-hypnotics

Classified as either:
•Sedative-hypnotic
•Anxiolytic

-Does not suppress REM as much as barbiturates
-Do not increase metabolism of other drugs
-PO administration does NOT depress respiration excessively

effective for insomnia short term

Question 6

Sedative-Hypnotic benzodiazepines

Answer 6

Lorazepam: intermediate acting

Midazolam: short acting

Question 7

Benzo mechanism

Answer 7

Enhances GABA

GABA reduces excitability of neurons

Question 8

Benzo adverse, interactions, considerations

Answer 8

Adverse: Drowsiness

Interactions: other CNS depressants. Grapefruit alters absorption

Question 9

Muscle relaxants

Answer 9

•relieve pain associated with skeletal muscle spasms

DRUG: Dantrolene
•For emergency treatment of malignant hyperthermia crisis
•Treatment of spasticity associated with spinal cord injury, CVA, CP, and MS