3.1 Sedative-Hypotonics And Anxiolytics Flashcards
1
Q
Sedated-hypnotic agents
A
- CNS depressants
- Magnitude of CNS depression produced by a drug at a particular dose determines what effect the agent produces
2
Q
Antianxiety
A
-Are used to treat anxiety disorders, such as generalized anxiety disorder obsessive compulsive disorder
3
Q
Sedation
A
-Used to relieve anxiety, decreased activity, moderate excitement, and generally, the individual
4
Q
Hypnosis (sleep)
A
-Used to produce drowsiness and eight in the onset and maintenance of sleep
5
Q
General anaesthesia
A
-Used to induce general anesthesia, which is a state of unconsciousness with an absence of pain sensation
6
Q
Controlling CNS excitation
A
- glutamate is the major excitatory neurotransmitter in the brain
- when a person is anxious or having difficulty sleeping, therapies and depressed overall brain activity, decreasing glutamate induced nerve firing
- can be done by increasing inhibitory signalling in the brain
7
Q
Drug classes
A
- class of drugs is a group of drugs with the same mechanism of action and similar pharmacological properties
- Thiopental secobarbital and phenobarbital are all drugs that ponder the barbiturate class of drugs
8
Q
How to increase inhibitory signalling in the brain
A
- Most brain activity involves excitatory neurons these release the neurotransmitter glutamate neurons fire when the excitatory input exceed inhibitory inputs
- Inhibitory signals from GABA Neurons increase with the most sedative hypnotics
- Increase and GABA Ronald firing results in decreased glutamate nerve firing
9
Q
GABA Signalling
A
- GABA is the primary inhibitory neurotransmitter in the CNS
- It causes inhibition by binding to an selectively opening chloride channels, resulting in hyper polarization of the postsynaptic membrane of a neuron
- Effective that is harder for the postsynaptic neuron to transmit incoming messages to other neurons, depressing overall CNS neuronal signalling
10
Q
Drugs that bind the chloride channel
A
- most sedative hypnotics modulate the chloride ion channel in the brain and spinal cord, but each binding to a different site on the chloride channel
- result is an increase in synaptic inhibition and thus a dampening of neuron responses in essence they enhance the inhibitory effect of GABA
11
Q
Benzodiazepines Mechanism of action
A
- ## activation of the Benzodiazepine receptor increases the frequency of the opening of the chloride channel
12
Q
Route of administration benzodiazepines
A
-Benzodiazepines are usually taken as a capsule or tablet, but some are available for intravenous use
13
Q
Lethality benzodiazepines
A
- most commonly involved in overdose
- wide margin of safety means death from overdose are rare
- deaths occurred following injection of Enormous doses, rapid intravenous injection of a large dose, or when a large dose was taken in combination with other drugs like alcohol
14
Q
Pharmacological properties of the benzodiazepines
A
- they possess a very high therapeutic index
- they produce antianxiety effects, sedation and amnesia
- they can decrease aggression
- some members of this group are effective hypnotics (drowsiness, facilitates onset and maintenance of sleep)
- they produce minimal suppression of rapid eye movement REM type sleep with hypnotic benzodiazepines (flurazepam) at normal doses
- they produce skeletal muscle relaxation (Diazepam)
- they have anti-convulsant action (diazepam)
- an antidote exist to reverse it’s effects in the case of an overdose (flumazenil)
15
Q
Effects of benzodiazepine short term use
A
- cns
- lungs
- motor coordination
16
Q
Short term use cns
A
The desirable affects our relaxation, calmness, and relief from anxiety or tension. Other effects may include drowsiness, lethargy, fatigue, and impairment of thinking and memory
17
Q
Short term use on lungs
A
-respiratory depression has been observed following rapid intravenous administration
18
Q
Short term use on motor coordination
A
-Moderate doses of all benzodiazepines can impaired motor coordination and driving. Patients taking these drugs during the day should refrain from driving or operating dangerous machinery
19
Q
Long term use of benzodiazepines
A
- vary between individuals, some large amounts for long periods of time without any major evidence of intoxication, but others will demonstrate symptoms
- impaired thinking, poor memory and judgement
- disorientation, incoordination
- slurred speech
20
Q
Benzodiazepines in the elderly
A
- benzodiazepines can produce cognitive disfunction in the elderly, should be used with caution, if at all, in this age group
- The elderly metabolize benzodiazepines more slowly than young adults, often leading to oversedation, falls, and injury
21
Q
Pregnant/breast-feeding
A
- benzodiazepines freely cross the placenta and distribute into the foetus
- benzodiazepine administered in the first trimester are associated with a small but significant risk of foetal abnormalities
- also secreted into the milk, exposing nursing infants to therapeutic or toxic doses of the drug, and can result in sedation or death
22
Q
Abuse potential benzodiazepines
A
- Low abuse lability, as they have weaker reinforcing properties then barbiturates, alcohol, opioids, and stimulants
- inherent harmfulness is low
- margin safety high
- do not depressed respiration therapeutic doses and therefore do not often lead to death on their own
23
Q
Tolerance benzodiazepines
A
- there’s not appear to be a problem
- can develop to…
- The sedative effects and impairment of coordination
- The anxiolytic effect (less common)
- to the euphoric effects (occasionally)
24
Q
Cross tolerance benzodiazepine
A
-Cross tolerance occurs among the benzodiazepine and other state of hypnotic drugs, such as barbiturates and alcohol, as they all modulate the chloride channel in the CNS
25
Dependence benzodiazepines
- Low for short term use
- mild but the stink withdrawal can occur after therapeutic use, exhibiting anxiety, headache, insomnia, tension, difficulty concentrating, and fatigue
- after chronic use sudden discontinuation may lead to withdrawal symptoms agitation, paranoia, seizures, and delirium
- less common than with barbiturates
26
Addiction benzodiazepines
- develop in some but not all
27
Benzodiazepines in sport
-Increase CNS depression in adults dependent manner helps reduce athletes anxiety because of low doses they act as anti-anxiety agents
28
Barbiturates
- potent CNS depressants classified according to their duration of action
- Long acting one to two days phenobarbital
- short acting 3 to 8 hours secobarbital
- ultra short acting 20 minutes thiopental
29
Barbiturates mechanism of action
-activation of the barbiturate receptor increases the duration of the opening of the chloride channel
30
Barbiturates clinical uses
- Limited
- ultra short acting and short acting barbiturates can be used to induce anaesthesia and someone acting agents can be used as antiepileptics
31
Barbiturates lethality
- replace by newer and safer drugs
- common especially when combined with alcohol
- specific antidote for barbiturate poisoning does not exist
- Death can also result during barbiturate withdrawal
32
Barbiturates administration
- different ways depending on what they are being used to treat
- in epilepsy, the route is oral
- To induce anesthesia, the route is intravenous
33
Pharmacology of barbiturates
- they possess a low therapeutic index call mom Jose to produce beneficial effect close to dose produce toxicity
- they demonstrate a full spectrum of those dependent CNS depression antianxiety sedation hypnosis general anaesthesia death
- There’s a pressroom type sleep. Ran sleep is essential so that we do not wake up with a feeling of not having slept or the feeling of a hangover
- they depress the respiratory system. This is a major problem and his dose dependent
- High doses depress the cardiovascular system, slowing the heart and lowering blood pressure
34
Short term effects of barbiturate
- Low doses resolved in Tranquility, relaxation, mild euphoria, reducing interest in one’s surroundings dizziness and mild impairment of motor coordination
- as does increase pleasurable state of intoxication and euphoria may occur
- cardiovascular and respiratory systems are depressed
- Sleep will ensue if the dose is sufficient
35
Long term use of barbiturates
-Memory, judgement and thinking are all impaired. The person exhibits hostility and mood swings, including depression
36
Potential for abuse of barbiturates
- equal to or greater than alcohol
- sometimes injected to obtain a rush affect
- pleasurable effects of some of the barbiturates give a significant degree of reinforcement
- inherent harmful is very high due to the risk of death from respiratory depression or from withdrawal
37
Tolerance for barbiturates
- can develop rapidly to sleep in duction in the mood affects of the barbiturates few weeks of nightly administration
- develops more slowly to the impaired motor coordination and slowed reaction time
- anti-convulsant actions develops much more slowly it does not appear to be a major problem clinically
- high cross tolerance between barbiturates and benzodiazepines
38
Dependence for barbiturates
- withdrawal syndrome occurs after discontinuation of chronic use
- Initially appears tremors, anxiety, weakness, and insomnia as well as postural hypotension, and made progress to include seizures, delirium, visual hallucinations, and a high body temperatures
- Individuals must be withdrawn slowly under medical supervision
39
Addiction barbiturate
- can result from regular use, irrespective of the dose
- users crave psychological effects of the drug, and feeling of panic may occur if they cannot get an adequate supply
- craving often persist long after use has stopped
40
Flumazenil
- Benzodiazepine receptor antagonist that blocks the effect of benzodiazepines.
- When taken an overdose, flumazenil can be administered as an antidote
41
Zolpidem
- find you a subset of the GABA receptors, causing sedation
- Disturb sleep patterns ram sleep even less than that benzodiazepines
- Appear to have more sedated effects as compared to anxiolytics effects
42
Buspirone
- does not act on the GABA receptor, rather at the serotonin receptor
- used in generalized anxiety states and may have an advantage over other sedatives and that it does not appear to have an additive effect with other sedative hypnotic drugs
43
Gamma hydroxybutyric acid (GHB)
- Agnes at a subset of GABA receptors, causing sedation and anaesthesia
- before causing sedation, GH because euphoria, a feeling of social closeness, enhance sensory perceptions, and amnesia
- Drug has been implicated as a date rape drug due to its amnestic properties without loss of consciousness
