CNS And PNS Flashcards
Central Nervous System consists of
Brain and spinal cord
Respiration’s controlled by
Pons and medulla
Neurotransmitters are
Norepinephrine, serotonin, and dopamine
CNS stimulants
Provoke release of neurotransmitters
Decrease reputable of neurotransmitters
Inhibit postsynaptic enzymes
Anxiety
Feeling tension, nervousness, apprehension, or fear involving unpleasant reactions to a stimulus
sedation
Loss of awareness and reaction to environmental stimuli
Hypnosis
Extreme sedation resulting in further CNS depression and sleep
The downers of CNS
Cause various degrees of depression
- sedative-hypnosis
- anesthetic
Sedatives
Treat sleep disorders
Sedative-hypnotics
Barbiturates
Benzodiazepines
Nonbenzodiazepines
General side effects of sedative hypnotics
Residual drowsiness Drug dependence Drug tolerance Withdrawal symptoms Respiratory depression
Benzodiazepines-AS A CLASS-
drug of choice to treat anxiety
Do not cause much sedation
Less likely to cause dependence-schedule 4 drug
Act by potentiating GABA
Benzodiazepines Indications
Anxiety disorders, alcohol withdrawal, hyper excitability, agitation, seizures, induction of anesthesia, conscious sedation, preoperative sedation
Benzodiazepines
Well absorbed GI tract, lipid soluble, metabolized by liver
Benzodiazepines Actions
Act in limbic system and the RAS Make GABA more effective Cause interference with neurons firing Lower doses assist with anxiety Higher doses cause sedation and hypnosis
Pharmacokinetics Benzo
Absorbed from GI tract Peak level 30 min to 2 hrs Lipid soluble and distributes well Cross placenta Enter breast milk Metabolize in liver Excretion in urine
Contraindications of Benzo
Allergy
Psychosis
Acute narrow angle glaucoma
Decrease liver and kidney function
Adverse effects of Benzo
CNS and anticholinergic effects
Use with causation in African Americans
Addictive effect with alcohol or narcotics
UNPREDICTABLE REACTION IN ELDERLY
Anxiolytics-used to depress CNS-of Benzo
Diazepam Chlordiazepoxide Lorazepam Aprazolam Oxazepam Clonazepam
GABA
Gamma-aminobutyric system
RAS
Reticular activating system
Benzodiazepines suffix
-zopam or -zolam
Benzodiazepine antidote
Flumazenil -romazicon
:inhibits effects of the benzodiazepines at the GABA receptors and is used to treat Benzo overdoses
NONbenzodiazepines
Zolpidem-ambien \:duration of action is 6-8 hrs Eszopiclone-lunesta Zaleplon-sonata Chloral hydrate Melatonin receptor agonist \:ramelteon-not a controlled substance
Barbiturates actions
CNS depressants
Inhibit neuroral impulse conduction in ascending RAS
Depress cerebral cortex
Depress motor output
Cause—sedation,hypnosis,anesthesia, and coma
Barbiturates Indications
Reliefs of signs and symptoms of anxiety Sedation Insomnia Preanesthesia Seizures
Pharmacokinetics barbiturates
Well absorbed, reached peak in 20-60 min, metabolizes in liver, excreted in urine
Adverse effects of Barbiturates
CNS depression Physical dependency Drowsiness Somnolence Lethargic Ataxia Vertigo Nausea/Vomiting Constipation
Long acting barbiturates
Phenobarbital and mephobarbital
Intermediate acting barbiturates
Amobarbital
Aprobarbital
Butabarbital
Short acting barbiturates
Pentobarbital
Secobarbital
Barbiturates
Controlled substance schedule 2 or 3
Many drug interactions including kava kava and valerian
Contraindications barbiturates
Allergy History of addiction to sedative Liver or kidney function Respiratory distress or depression Pregnancy
Adverse effects or barbiturates
Respiratory depression
hangover
Do NOT withdrawal abruptly or mix with alcohol
General anesthetics
CNS depressants used to produce loss of pain sensation and consciousness