What are seditives commonly used for? What are the 3 major types SPF anxiety?
To reduce anxiety induce sleep.
1. Anxiety attacks
2. Situational anxiety
3. Generalized anxiety disorder
List three families of sedatives.
1. GHB (gamma hydroxybutyric acid)
Explain the chemical nature of how sedatives work.
they activate chloride ion channel in neural membranes by activating GABA Receptors. When GABA binds It opens a specific ion channel allowing more chloride into the cell. This increase negative potential in the cell causing hyper polarization inhibiting post neuron firing.
What stimulation causes reduction in anxiety?
GABA stimulation in limbic System.
Stimulation that promotes sleep.
GABA stimulation in cortical areas
Stimulation inducing amnesia
GABA stimulation in hippocampus and cerebral cortex
what determines if a sedative induces sleep or relieves anxiety?
Dosage. Low dose = anxiety
What does GHB stand for?
Gamma hydroxybutyric acacid trade name xyrem
what is GHB used for?
Legally prescribed for sedation in large doses. Commonly used as illegal date rape.
Why are barbiturates not commonly used?
Low therapeutic index with side effects of respiratory depression and high physical dependence.
How did barbiturates work?
Directly stimulating inhibitory gaba type chloride channels as well as inhibiting types of stimulatory receptors. This leads to reduction of CNS activity
Name three barbiturates.
2- sodium Pentothal (thiopental)
3- fiorinal or fiorcet
What barbiturate is used to tx seizures?
What barbiturate is used for induction of anesthesia ?
Sodium Pentothal (thiopental )
What barbiturates are used for tension head aches and migranes?
Fiorinal and fioricet
What are two major adverse effects of barbiturates?
- respiratory depression
- physical dependence
How do benzodiazepines work?
By potentiating effect of naturally occurring gaba but is limited by naturally occurring gaba.
true or false: benzodiazepines are lipophobic.
FalseFalsies!! Lipophilic :)
What do benzodiazepines treat?
Anxiety, insomnia, delirium tremens, status epilepticus and amnesia.
What are some adverse effects of benzodiazepines?
- psychological dependence
- sudden withdrawal will have serious effects
Name three benzodiazepines with a brief explanation.
- alprazolam (xanax): tx anxiety and panic attacks
- lorazepam (ativan): most commonly used. tx anxiety and withdrawal symptoms from alcoholics
-Diazepam (valium): occasionally used for anxiety before sx or dental procedures, muscle spasticity, status epilepticus.
what are some clinical symptoms of parkinson's disease?
produces movement disorders called dyskinesias.
this includes tremors, rigidity, bradykinesia, disturbed posture, and akinesia. Leads to psychological disturbances.
Give a chemical explanation of Parkinson's.
Due to lack of dopamine in striatum of brain. Balance must be maintained between Dopamine and aceytlecholine.
what produces dopamine?
substantia nigra cells in the striatum.
What are two possible unique situations causing parkinson's?
1. contamination of methyl fentanyl (heroin like street drug)
2. cycad seed flour, eaten in guam, containing brain neurotoxin.
Why cant dopamine be given orally?
It will be metabolized quickly.
It will not cross the BBB.
It will cause other undesired effects.
What are three treatment methods of Parkinson's?
1. give a dopamine precursor
2. give a dopamine analog agonist
3. inhibit rate of dopamine metabolism.
Name a dopamine precursor.
Levodopa, or L-DOPA
How does L-DOPA become Dopamine?
It is converted by an enzyme called DOPA decarboxylase
How must L-DOPA (if given alone) be given and why is this negative?
It must be given in high doses. This high dose causes increased heart rate and blood pressure.
What is carbidopa?
Carbidopa is an inhibitor of DOPA decarboxylase that does not cross the BBB which when combined with L-DOPA allows L-DOPA to reach the brain before being converted to Dopamine.
What is the most common dopamine precursor?
What are L-DOPA/carbidopa's side effects?
1. GI disturbances
2. orthostatic hypotension
3. movement disorders
4. on-off efficacy
5. tachycardia due to B1 stimulation
6. aggravation of adverse anti-psychotic drugs
what is a downfall of L-DOPA?
efficacy does not last indefinitely.
Name three dopamine agonists.
1- pramipexole (mirapex)
2- ropinrole (Requip)
3- Bromocriptine (Parlodel)
What are dopamine agonists?
molecules which imitate the action of dopamine. must be able to cross BBB.
Name the generic name and adverse effects for Mirapex
somnolence, sudden sleep attacks
Give the generic name and adverse effects for Requip