Central Nervous System Drugs Flashcards
Neuropharmacology
It is a study of drugs that alter processes controlled by the nervous system
How neurons regulate other cells?
A. Axonal Conduction
- conducting an action potential down the axon of the neuron.
B. Synaptic Transmission
- process by which information is carried across the gap between neuron and postsynaptic cell
CNS Drugs
Used for psychiatric disorders, suppression of seizures, relief of pain, production of anesthesia.
Blood Brain Barrier
- Impedes the entry of the drugs into the brain
- Passage is limited to lipid-soluble agents or via specific transport systems
CNS STIMULANTS: Amphetamines
Stimulate the release of NE and DA from the brain and SNS
1. Methylphenidate
- given to increase child’s attention span and cognitive performance
- used to treat narcolepsy
2. Modafinil
- treatment of narcolepsy
3.Analeptics: Xanthine
- stimulate respiration
4. Doxapram
- treatment of respiratory depression caused by drug overdose and COPD
CNS contains 21 compounds that serve as neurotransmitters
MONOAMINE
-Dopamine
-Epinephrine
-Serotonin
AMINO ACID
-Aspartate
-GABA
-Glutamate
-Glycine
PURINE
-Adenosine
-Adenosine monophosphate
-Adenosine triphosphate
OPIOID PEPTIDES
-Dynorphines
-Endorphins
-Enkaphalins
NOMOPIOID PEPTIDES
-Neurotensin
-Oxytocin
-Somatostatin
-Substance P
-Vasopressin
OTHERS
-Acetycholine
-Histamine
-GABA
Tolerance and Physical Dependence
Tolerance- decreased response occurring in the course of prolonged drug use
Physical Dependence- state in which abrupt discontinuation of drug use will precipitate a withdrawal syndrome
Parkinson’s Disease
-Slowly progressive neurodegenerative disorder characterized by tremor, rigidity, postural instability and slowed movement
-Affects the extrapyramidal system which influences movement
Drugs deployed
- Dopaminergic drugs- directly/indirectly cause activation of dopamine receptors
- Anticholinergic Agents- drugs that block receptors for ACh
Dopaminergic Drugs: Drug Interactions
- Reduced when taking pyridoxine [VIT B6], phenytoin, benzodiazepines, reserpine and papaverine
- Use with MAOI increases the risk of hypertensive crisis
- Use with antipsychotic reduces the effectiveness of levodopa
- Amantadine may increase anticholinergic adverse effects
Bind to a carrier protein and act at a receptor resulting in increased GABA in the brain
Gabapentin
It is the most commonly prescribed anticonvulsant drug
Phenytoin
It is effective against partial seizures and generalized tonic-clinic seizures but not absence seizures
Phenobarbital
Excitation undergoes limited spread from the focus to adjacent cortical areas
Partial seizures
Excitation spreads widely throughout both hemisphere of the brain
Generalized seizures
