Pharmacodynamic- Organ level effect

Question 1

Sedation— Benzodiazepines, barbiturates, and most older
sedative-hypnotic drugs exert ___________

Answer 1

calming effects with concomitant
reduction of anxiety at relatively low doses.

Question 2

In most cases, however,
the anxiolytic actions of sedative-hypnotics are accompanied
by some depressant effects on ____________

Answer 2

psychomotor and cognitive
functions.

Question 3

In experimental animal models, benzodiazepines and
older sedative-hypnotic drugsare able to disinhibit ___________

This disinhibition has been equated with
antianxiety effectsof sedative-hypnotics, andit is not a characteristic
of all drugs that have sedative effects, eg, the tricyclic
antidepressants and antihistamines.

Answer 3

punishmentsuppressed
behavior.

Question 4

However, the disinhibition
of previously suppressed behavior may be more related to behavioraldisinhibitory effects of sedative-hypnotics, including
_____________which can
occur at dosages in the range of those used for management of
anxiety.

Answer 4

• euphoria,
• impaired judgment,
• and loss of self-control,

Question 5

The benzodiazepines also exert dose-dependent ____________________(inability to remember events occurring
during the drug’s duration of action).

Answer 5

• *anterograde**
• *amnesic effects**

Question 6

Organ Level Effects

Answer 6

1. Sedation
2. Hypnosis
3. Anesthesia
4. Anticonvulsant effects
5. Muscle relaxation
6. Effects on respiration and cardiovascular function

Question 7

By definition, all of the sedative-hypnotics
induce sleep if high enough doses are given. The effects of sedativehypnotics
on the stages of sleep depend on several factors,
including the specific drug, the dose, and the frequency of its
administration. The general effects of benzodiazepines and older
sedative-hypnotics on patterns of normal sleep are as follows:

Answer 7

(1) the latency of sleep onset is decreased (time to fall
asleep) ;

(2) the duration of stage 2 NREM (nonrapid eye movement)
sleep is increased;

(3) the duration of REM sleep is decreased; and

(4) the duration of stage 4 NREM slow-wave
sleep is decreased.

Question 8

A sedative is a drug that **produces a relaxing, calming effect. **

Sedatives are usually given during daytime hours,and although they may make the patient drowsy, they usually **do not produce sleep. **

A hypnotic is a drug that induces sleep, that is, it allows the patient to fall a sleep and stay a sleep.

Hypnotics also may be called soporifics. Hypnotics are given at night or hour of sleep (HS).

Question 9

The newer hypnotics all decrease the____________

Answer 9

latency
to persistent sleep.

Question 10

__________-decreases REM sleep but has
minimal effect on slow-wave sleep.

Answer 10

Zolpidem

Question 11

• *_________**decreases the
• *latency of sleep onset w**ith little effect on total sleep time,
• *NREM, or REM sleep.**

Answer 11

**Zaleplon **

Question 12

____________ increases total sleep time,
mainly via increases in stage 2 NREM sleep, and at low doses has
little effect on sleep patterns. At the highest recommended dose,
decreases REM sleep.

Answer 12

Eszopiclone

Question 13

More rapid onset of sleep and prolongation of stage 2 are
presumably clinically useful effects.

However, the significance of
sedative-hypnotic drug effects on REM and slow-wave sleep is
not clear.

Deliberate interruption of REM sleep causes anxiety
and irritability followed by a rebound increase in REM sleep at
the end of the experiment.

Question 14

A similar pattern of “REM rebound”
can be detected following** abrupt cessation of drug treatment
with older sedative-hypnotics,**especially when drugs with _______________

Answer 14

short
durations of action (eg, triazolam) are used at high doses.

Question 15

With
respect to_____________ there is little
evidence of REM reboundwhen these drugs are discontinued
after use of recommended doses.

Answer 15

zolpidem and** the other newer hypnotics,**

Question 16

However, rebound insomnia
occurs with both ____________- if used at higher doses.

Answer 16

zolpidem and zaleplon

Question 17

Despite possible reductions in slow-wave sleep, there are no
reports of disturbances in the secretion of pituitary or adrenal
hormones when either barbiturates or benzodiazepines are used
as hypnotics.

The use of sedative-hypnotics for more than______________ leads to some tolerance to their effects on sleep patterns.

Answer 17

** 1–2
weeks**

Question 18

high doses of certain
sedative-hypnotics depress the central nervous system to the point known as_____________ (see Chapter 25 ).
However, theagent ** suitability of a particular **as an adjunct in anesthesia depends mainly on the physicochemical properties that
determine its rapidity of onset and duration of effect.

Answer 18

stage III of general anesthesia

Question 19

Among the
barbiturates, _____________ are very lipid-soluble,
penetrating brain tissue rapidly following **intravenous administration, **a characteristic favoring their use for the induction of anesthesia.
Rapid tissue redistribution (not rapid elimination) accounts
for the short duration of action of these drugs, a feature useful in
recovery from anesthesia.

Answer 19

thiopental and methohexital

TM

Question 20

Not surprisingly,
benzodiazepines given in large doses as adjuncts to general anesthetics
may contribute to a persistent postanesthetic respiratory
depression.

This is probably related to their relatively long halflives
and the formation of active metabolites. However, if necessary,
such depressant actions of the benzodiazepines are usually
reversible with flumazenil.

Answer 20

long halflives

and the formation of active metabolites

Question 21

Many sedative-hypnotics are
capable of inhibiting the development and spread of epileptiform
electrical activity in the central nervous system.

Some selectivity
exists in that some members of the group can exert anticonvulsanteffects without marked central nervous system depression (although psychomotor function may be impaired).

Several
____________—are sufficiently selective to be clinically useful in
the management of seizures (see Chapter 24 ).

Answer 21

benzodiazepines—

including clonazepam, nitrazepam, lorazepam,
and diazepam

Question 22

Of the barbiturates,
______________ are effective in the treatment of generalized tonic-clonic
seizures,thoughnot the drugs of first choice.

Answer 22

• phenobarbital and
• metharbital (converted to phenobarbital in the

body)

Question 23

____________ lack anticonvulsant activity, presumably because
of their more selective binding than that of benzodiazepines to
GABA A receptor isoforms

Answer 23

Zolpidem, zaleplon,
and eszopiclone

More selevtive kasi sya!!!

Question 24

Some sedative-hypnotics, particularly
members of the _____________ exert inhibitory effects on polysynaptic reflexes and internuncial
transmissionandat high doses may also depress transmission
at the skeletal neuromuscular junction.

Somewhat selective
actions of this type that lead to muscle relaxation can be readilydemonstrated in animals and have led to claims of usefulness forrelaxing contracted voluntary muscle in muscle spasm (see Clinical
Pharmacology).

Answer 24

carbamate (eg, meprobamate) and benzodiazepine
groups,

Question 25

Muscle relaxation is not a characteristic action of \_\_\_\_\_\_\_\_\_\_\_\_-

Answer 25

zolpidem, zaleplon, and eszopiclone. ZEZ! Kasi nga diba selective sya: So ***_no_*** **anticonvulsant effect and muscle relaxation effect**

Question 26

At hypnotic doses in healthy patients, the effects of sedative-hypnotics on respiration are comparable to changes during natural sleep. However, **even at therapeutic doses,** **sedative-hypnotics can produce significant respiratory depression in patients with** \_\_\_\_\_\_\_\_\_\_\_\_

Answer 26

pulmonary disease. Kaya careful sa merong mga pulmo probs

Question 27

**Effects on respiration are dose-related,** and **depression of the medullary respiratory center i**s the**usual cause of death due to overdose of sedative-hypnotics.**

Question 28

At doses up to those **causing hypnosis**, **no significant effects on the cardiovascular system** are observed in healthy patients. However, in **hypovolemic states,** heart failure, and other diseases that impair cardiovascular function, normal doses of sedativehypnotics may cause **cardiovascular depression,** probably as a \_\_\_\_\_\_\_\_\_\_.

Answer 28

result of actions on the medullary vasomotor centers

Question 29

At toxic doses, **myocardial contractility** and **vascular tone** may **both be depressed**by central and peripheral effects, leading to circulatory collapse. Respiratory and cardiovascular effects are more marked when sedative-hypnotics are **given intravenously.**