BASIC PHARMACOLOGY OF SEDATIVEHYPNOTICS Flashcards
Two examples of such dose-response relationships are shown in Figure 22–1 .
The linear
slope for drug A is typical of many of the older sedative-hypnotics, including the barbiturates and alcohols. With such drugs, an increase in dose higher than that needed for hypnosis may lead to _________________.
a state of general anesthesia.
At still higher doses, these sedativehypnotics
may depress respiratory and vasomotor centers in the
medulla, leading to coma and death.
An effective sedative (anxiolytic) agent should _______ and ____________.
The degree of central nervous system
depression caused by a sedative should be the minimum consistent
with therapeutic efficacy
reduce anxiety and
exert a calming effect
. A hypnotic drug should produce__________ and __________
Hypnotic effects involve more pronounced depression of the central
nervous system than sedation, and this can be achieved with
many drugs in this class simply by increasing the dose.
drowsiness
and encourage the onset and maintenance of a state of sleep.
__________depression of central nervous system function is a
characteristic of most sedative-hypnotics. However, individual
drugs differ in the relationship between the dose and the degree of
central nervous system depression.
Graded
dose-dependent
Certain antihistaminic agents
including diphenhydramine, hydroxyzine, and promethazine (see
Chapter 16 ) cause sedation but commonly also exert marked
effects on the peripheral autonomic nervous system. Antihistaminic
drugs with sedative effects are available as over-the-counter
sleep aids.
The___________are widely used sedative-hypnotics.
benzodiazepines
Note: All of
the structures shown in Figure 22–2 are 1,4-benzodiazepines, and
most contain a carboxamide group in the 7-membered heterocyclic ring structure.
An electronegative substituent in the 7 position,
such as a halogen or a nitro group, is required for
sedative-hypnotic activity. The structures of triazolam and alprazolam
include the addition of a triazole ring at the 1,2-position.
The chemical structures of some older and less commonly usedsedative-hypnotics, including several barbiturates , are shown in
Figure 22–3 .
\_\_\_\_\_\_\_\_\_\_\_\_ are of **distinctive chemical structure**but are**practically equivalent to barbiturates** in their **pharmacologic effects.** They are rarely used. The sedative-hypnotic class also includes compounds of simpler chemical structure, including **ethanol** (see Chapter 23 ) and **chloral hydrate**.
Glutethimide and meprobamate
Several drugs with novel chemical structures have been introduced more recently for use in sleep disorders.______________ ( Figure 22–4 ), although structurally
unrelated to benzodiazepines, share a similar mechanism of
action, as described below.
Zolpidem , an
imidazopyridine, zaleplon , a pyrazolopyrimidine, and eszopiclone
, a cyclopyrrolone ( Figure 22–4 ), although structurally
unrelated to benzodiazepines, share a similar mechanism of
action, as described below.
___________ is the (S) -enantiomer of
zopiclone, a hypnotic drug that has been available outside the
United States since 1989. Ramelteon , a melatonin receptor agonist,
is a more recently introduced hypnotic drug (see Box:
Ramelteon).
Eszopiclone
______________-is a slow-onset anxiolytic agent whose
actions are quite different from those of conventional sedative-hypnotics
Buspirone
Other classes of drugs that exert sedative effects include ___________(see Chapter 29 ) and many___________** **(see
Chapter 30 )
**antipsychotics **
** antidepressant drugs**
Antidepressants are currently used widely in the management
of chronic anxiety disorders.
Certain antihistaminic agents
including _____________(see
Chapter 16 ) cause sedation but commonly also exert marked
effects on the peripheral autonomic nervous system.Antihistaminic
drugs with sedative effects are available as over-the-counter
sleep aids.
diphenhydramine, hydroxyzine, and promethazine
