PS268 Chapter Notes - Chapter 7: Chloral Hydrate, Generalized Anxiety Disorder, Epilepsy

64 views5 pages
Published on 20 Apr 2013
School
WLU
Department
Psychology
Course
PS268
Professor
Drugs and Behaviour - Chapter 7 (139-153)
Brian Kwok 1
History and pharmacology of depressants
o Depressant drugs share many characteristics with alcohol
o Before barbiturates
Number of medications used prior to introduction of barbiturates
Chloral hydrate
1870 started being used clinically
Has short onset of action and 1-2g will induce sleep in less than an hour
Chloral hydrate abusers grouped with alcohol intempereants and opium eaters
Gastric irritant and can cause considerable stomach upset
Pharldehyde
1882 started being used clinically
Has noxious taste, but may be of great use as CNS depressant because of wide
safety margin
Use discontinued in 2007
Bromides
Used widely to induce sleep
Accumulates in body and cause build up over several days of regular use
Severe toxic effects following repeated hypnotic doses
Dermatitis and constipation, motor disturbance, delirium and psychosis are side
effects
o Barbiturates
More than 2500 types synthesized
Veronal first clinically used in 1903
o All barbiturates end with al
Most lipid-soluble drugs have shortest onset time and quickest duration of action
Low dose of long acting barbiturate calm and relaxed for long period
Higher dose of short acting sleeping pill
Activates CYP450 enzymes of liver
Some tolerance develops
Psychological and physical depend can develop
Depress respiration
o Combined with alcohol, can stop person’s breathing
Barbiturate sleeping pills were chosen above others as suicide pill
Accidental overdoses often occurred too
Great deal of concern about abuse potential and danger of overdose
o Meprobamate
Believed to be a unique type of CNS depressant
Marked as an anxiolytic, became popular with drug abusers
Produced barbiturate-like euphoria and pleasure
o Prescribing and use gradually decreased
Schedule III drug
Combination product 282-MEP
o Used for treatment of pain associated with muscle tightness
o Methaqualone
Synthesized in India, found to have sedative properties
Very high rates of overdose
Tolerance develops very quickly, creates euphoric effects
Repeated administration results in physical dependence, severe withdrawal related psychotic
symptoms and life threatening seizure activity
Schedule IV drug
Unlock document

This preview shows pages 1-2 of the document.
Unlock all 5 pages and 3 million more documents.

Already have an account? Log in
Drugs and Behaviour - Chapter 7 (139-153)
Brian Kwok 2
o Benzodiazepines
First was chlordiazepoxide
First synthesized in 1947
Marketed as more selective anti-anxiety agent, produced less drowsiness and larger
safety argin
Physical dependence was almost unheard of and overdose didn’t occur in
combination with alcohol
As effective as barbiturates and much safer
Valium (diazepam) replaced in 1970
Xanax (alprazolam) mostly prescribed
As drugs became widely used, physical dependence, psychological dependence and
overdose deaths appeared
Over dose deaths
o More likely when drug sold in higher doses than prescribed
Psychological dependence
o Develops most rapidly when drug hits brain
Physical dependence
o Occurs when drug leaves system more rapidly than body can adapt
Chlordiazepoxide
Slow onset of action
Longer duration of action
Produces few problems
Most frequently prescribed psychotropic medication
Variety of psychiatric and medical condition
Anxiety disorders
Sleep disorders
Seizure disorders
Movement disors
Muscle spasticity
Used in anaesthesiology and symptomatic treatment of agitation associated with
other disorders
Mechanism of Action of Benziodazepines
o Effects of sedative-hypnotic agents found in 1977
o Benzodiazepine receptors always ear receptors for amino acid neurotransmitter GABA
Enhance normally inhibitory effects of GABA on its receptor
o Barbiturates act at separate binding site and increase the actions of GABA on its receptors as well
o Different subtypes of GABA receptors identified
Structurally different and activated or blocked by different drugs
o Benzodiazepines do not independently activate flow of chloride ions into neuron
Facilitate action of primary inhibitory neurotransmitter to increase flux of chloride ions into
neuron
o Tolerance usually develops among people receiving maintenance therapy with stable dose
o Overdoses almost never fatal unless combining with other sedative agents
Beneficial Uses of Depressants
o Anxiolytics
Drugs used to reduce anxiety
Used to accept that various types of dysfunctional behaviour resulted from various forms of
psychological stress and can be lumped under “anxieties”
Not all conditions can be treated with antianxiety drugs
Most benzodiazepines prescribed for anxiety disorders
Unlock document

This preview shows pages 1-2 of the document.
Unlock all 5 pages and 3 million more documents.

Already have an account? Log in

Document Summary

History and pharmacology of depressants: depressant drugs share many characteristics with alcohol, before barbiturates. Number of medications used prior to introduction of barbiturates. Has short onset of action and 1-2g will induce sleep in less than an hour. Chloral hydrate abusers grouped with alcohol intempereants and opium eaters. Gastric irritant and can cause considerable stomach upset. Has noxious taste, but may be of great use as cns depressant because of wide safety margin. Accumulates in body and cause build up over several days of regular use. Severe toxic effects following repeated hypnotic doses. Dermatitis and constipation, motor disturbance, delirium and psychosis are side: barbiturates effects. Veronal first clinically used in 1903: all barbiturates end with al. Most lipid-soluble drugs have shortest onset time and quickest duration of action. Low dose of long acting barbiturate calm and relaxed for long period. Higher dose of short acting sleeping pill. Depress respiration: combined with alcohol, can stop person"s breathing.

Get OneClass Grade+

Unlimited access to all notes and study guides.

YearlyMost Popular
75% OFF
$9.98/m
Monthly
$39.98/m
Single doc
$39.98

or

You will be charged $119.76 upfront and auto renewed at the end of each cycle. You may cancel anytime under Payment Settings. For more information, see our Terms and Privacy.
Payments are encrypted using 256-bit SSL. Powered by Stripe.