Anxiolytic and Hypnotic Drugs Flashcards
What does it mean for a drug to be an anxiolytic?
Gives calming effects and relief of anxiety
What does it mean for a drug to be a hypnotic?
Promotes drowsiness, promotes onset and maintenance of sleep
What are some examples of benzodiazepines?
Lorazepam, diazepam, chlordiazepoxide, triazolam
What are some examples of barbituates?
Thiopental, pentobarbital
What are some examples of other anxiolytic and hypnotic drugs?
Buspirone, zopiclone
How do benzodiazepines work?
Bind to the GABA-A receptor and enhance its GABA actions to reduce the excitability of the neurons and increases the frequency of channel-opening events
CNS depressants
Low affinity for GABA-B
What is GABA?
The primary inhibitory neurotransmitter in the brain
What is the GABA-A receptor?
A chloride channel that allows chloride influx, hyperpolarizes neurons and decreases neuronal activity
How do barbituates work?
Bind to GABA-A and increase the duration of channel-opening events
Inhibit glutamate AMPA receptor
GABA-mimetic at high doses
What determines the speed of onset of these drugs?
The lipophilicity of the drug or its ability to cross the BBB
Triazolam has the fastest onset of benzodiazepines.
What determines the duration of effects of these drugs?
Redistribution due to lipophilicity
Biotransformation (phase I, CYP P450, conjugation-phase II) made more water-soluble
Many phase I metabolites of benzodiazepines are active
Which benzodiazepines have short half-lives?
Lorazepam, oxazepam, alprazolam, triazolam
Which benzodiazepines have long half-lives?
Chlordiazepoxide, diazepam, prazepam, flurazepam
Which benzodiazepines are used for hypnotics or anxiolytics?
Short half lives for hypnotic
Long half lives for anxiolytic (cumulative effects with multiple doses)
Which populations should be special consideration for benzodiazepine use?
Pregnant and breastfeeding patients, older patients, those with liver disease, obese patients
How do the duration of action of barbiturates vary?
Ultra short acting (30 minutes): Thiopental for induction of anesthesia Short acting (18-48 hours): Secobarbital, phenobarbital for hypnotic and sedative Long acting (4-5 days): Phenobarbital for seizures
What are the therapeutic uses of benzodiazepines?
Relief of anxiety
Treatment of insomnia
Sedation and amnesia before and during surgical procedures
Treatment of epilepsy and seizure states
Muscle relaxation in specific neuromuscular disorders
Control of ethanol or other sedative-hypnotic withdrawal
What are some examples of anxiety disorders?
Generalized anxiety disorder (GAD), panic disorder, social phobia, PTSD, OCD
What are some symptoms of anxiety disorders?
Feelings of panic, fear and uneasiness, uncontrollable, obsessive thoughts, nightmares, sleeping problems, cold or sweaty hands, shortness of breath, numbness or tingling in hands or feet, muscle tension, nausea, dry mouth
How are benzodiazepines used in anxiety treatment?
Used for the management of acute anxiety states and for rapid control of panic attacks
Alprazolam
What is the first choice treatment for long term management of GAD and panic disorders?
Selective serotonin reuptake inhibitors (SSRIs)
What are some symptoms of insomnia?
Sleep deprivation from trouble falling asleep or staying asleep.
Lying awake for a long time before falling asleep, sleeping for short periods, waking up too early