Drugs affecting the Nervous System Flashcards
True or False
The activities of the central and peripheral nervous system are coordinated and integrated. Drugs may alter the physiological processes at receptor sites of the nervous system.
True
Describe the effects of sympathomimetic drugs (adrenergic agonist)
- Produce their effects by activating adrenergic receptors
- Sympathetic nervous system acts through these same receptors, responses to adrenergic agonists and responses to stimulation of the sympathetic nervous system are very similar
Explain the effects of sympatholytics drugs (adrenergic antagonist)
- Cause direct blockage of adrenergic receptors
* One exception, all of the adrenergic antagonists produce reversible (competitive) blockade.
Explain the effects of parasympathomimetics drugs (cholinergic agonists)
• The muscarinic agonists bind to muscarinic receptors and thereby cause receptor activation.
Define cholinergic crisis
Overdose with cholinesterase inhibitors causes excessive muscarinic stimulation and respiratory depression. This state produced by the over dose is referred to as cholinergic crisis
Describe the effects of parasympatholytics drugs ( anticholinergics or cholinergic antagonists)
• Muscarinic antagonists competitively block the actions of acetylcholine at muscarinic receptors.
Additional names for these agents are antimuscarinic drugs, muscarinic blockers, and anticholinergic drugs.
What are Anxiolytic?
Agents given to relieve anxiety
What are Hypnotics?
Agents given to promote sleep
What are the effects of Benzodiazepines?
○ Depresses neuronal function at multiple sites in the CNS
○ Reduce anxiety through effects on the limbic system, a neuronal network associated with emotionality
○ Promotes sleep through effects on cortical areas and on the sleep-wakefulness clock
○ Induce muscle relaxation through effects on supraspinal motor areas, including cerebellum
What are the effects of Barbiturates?
○ Daytime sedation ○ Induction of sleep ○ Suppression of seizures ○ General Anesthesia ○ Causes tolerance and dependence, high abuse potential ○ Powerful respiratory depressant ○ CNS depression
Compare acute and chronic pain.
- Chronic Pain: Pain over a long period of time
* Acute Pain: Acute pain attack
Describe tonic-clonic seizure.
• The neuronal discharge spreads through both hemispheres of the cerebral cortex
• They manifest as major convulsions
○ Characterized by period of muscle rigidity (tonic phase)
Followed by synchronous muscle jerks (clonic phase)
- Often cause urination, but not defecation
- Convulsions may be preceded by a loud cry, caused by forceful expiration of air across the vocal cords
• Accompanied by marked impairment of consciousness, followed by a period of CNS depression
○ Referred to as the postictal state
• Lasts 90 seconds or less
Discuss the deleterious effects of unrelieved pain
- Pain has profound impact on both patient and family
- Undermines quality of life
- Puts heavy burden on family
- Compromises the pt’s ability to work, enjoy leisure activities, and fulfill his/her role in the family & society at large
- Pain can impede recovery
- Hasten death from cancer
- Create risk of suicide
Define abuse
using a drug in a fashion inconsistent with medical or social norms
Define addiction
chronic, relapsing brain disease that is characterized by compulsive drug seeking use, despite harmful consequences
Define physical dependence
state in which an abstinence syndrome will occur if drug use is discontinued.
○ Result of neuradaptive processes that take place in response to prolonged drug exposure
What are Symptoms of inflammation:
○ Pain
○ Swelling
○ Redness
○ Warmth
What can consist of a postsynaptic cell?
- another neurone
- a muscle cell
- or a cell within a secretory gland
What are the 2 steps in the process by which the neurone influences the behaviour of the postsynaptic cell?
1) Axonal Conduction
2) Synaptic Transmission
True or False
The impact of a drug on a neuronal regulated process is dependent of the ability of that drug to directly or indirectly influence the receptor activity on target cells
TRUE
Which process is more SELECTIVE?
Axonal Conduction or Synaptic Transmission
Synaptic Transmission
What does the effects of neuropharmacologic drugs affect?
the receptor activity
True or False
A drug that alters axonal conduction will affect the conduction in all nerviest to which it has access?
TRUE
True or False
Drugs that alter synaptic transmission are more selective, and unlike axons differ from one and other. Synapses at different sites employ different transmitters?
TRUE
What are the Steps in Synaptic Transmission?
1) Transmitter Synthesis
2) Transmitter Storage
3) Transmitter Release
4) Receptor Binding
5) Termination of Transmission
When a drug influences receptor function, that drug can do one of two things: what are they?
1) it can ENHANCE receptor activation, or
2) it can REDUCE receptor activation
A drug whose effects mimic the effects of a natural transmitter would be said to _______ receptor activation. A drug whose effects were equivalent to reducing the amount of natural transmitter available of receptor binding would be said to _______ receptor activation
Increase, decrease
True or False
The activation of a receptor always means that a physiologic process will go faster.
FALSE
What are drugs that prevent receptor receptor activation called?
Antagonists
What are drugs that directly activate receptors ?
Agonists
The more types of receptors we have to work with, the_________ our chances of producing selective drugs effects.
a) greater
b) lesser
a) greater
What does PNS stand for?
Peripheral Nervous System
What are the 2 major subdivisions of the PNS?
1) Somatic motor system
2) Autonomic nervous system
What doe the somatic motor system control?
voluntary movement of muscles
What are the 2 subdivisions of the autonomic system?
- parasympathetic nervous system
- sympathetic nervous system
The 2 subdivisions of the autonomic nervous system regulates many _______ processes.
involuntary
What are the principal functions of the autonomic nervous system?
1) regulation of the heart
2) regulation of secretory glands
3) regulation of smooth muscles
Which nervous system
- slows down the heart rate
- increases gastric secretion
- empties the bladder and bowel
- focuses the eye for near vision
- constructs the pupils
- contracts bronchial smooth muscle
Parasympathetic
What are the principal functions of the sympathetic nervous system?
- regulation of the cardiovascular system
- regulation of body temperature
- implementation of the fight or flight response
What are the 3 transmitters of the peripheral nervous system?
1) acetylcholine
2) norepinephrine
3) epinephrine
What are the categories of cholinergic drugs
Muscarinic agonist Muscarinic antagonist Ganglionic stimulating agents Ganglionic blocking agents Neuromuscular blocking agents Cholincesterase inhibitors
What is the difference between a sedative and a hypnotic drug?
Sedatives are drugs that decrease activity and have a calming, relaxing effect. People use these drugs mainly to reduce anxiety.
At higherdoses, sedatives usually cause sleep. Drugs used mainly to cause sleep are called hypnotics.
The difference between sedatives and hypnotics, then, is usually the amount of the dose-lower doses have a calming effect and higher doses cause sleep.
What are commonly used for sedation?
Currently, the most commonly prescribed sedatives are benzodiazepines, such as Valium. These drugs are also known as minor tranquilizers.
What is a Benzodiazepines?
Bind to GABA receptor chloride channels
Used for anxiety, insomnia, seizure disorders
Adverse effects: anterograde amnesia, confusion, ataxia
What is a Barbiturate
Bind to GABA receptor chloride channels
Insomnia, induction of anesthesia, inhibit seizure activity.
Adverse effects: “hangover effects”, respiratory depression; hypotension (at toxic doses)
Tolerance/physical dependence
Name some examples of benzodiazepines
Examples lorazepam (Ativan) diazepam (Valium) alprazolam (Xanax) oxazepam (Serax) chlordiazepoxide (Librium) flurazepam (Dalmane) temazepam (Restoril) midazolam (Versed)
Name examples of barbiturates
Pentobarbital (Nembutal) Secobarbital (Seconal) Thiopental sodium (Pentothal) Phenobarbital (Luminal) Primidone (Mysoline)
What are some adverse effects of opioids?
Cough suppression Constipation Sedation Urinary retention Orthostatic hypotension Respiratory depression Emesis Miosis Biliary colic Increased intracranial pressure Tolerance Physical dependence Toxicity : coma, respiratory depression, pinpoint pupils
What is a Percocet?
acetaminophen and oxycodone
What is a Percodan?
aspirin and oxycodone
Drugs can activate adrenergic receptors by what 4 basic mechanisms?
○ Direct receptor binding
○ Promotion of norepinephrine release
○ Blockage of NE reuptake
○ Inhibition of NE inactivation
Most adrenergic antagonists are more selective as a result, the adrenergic antagonists can be divided into what 2 groups?
○ Alpha-adrenergic blocking agents
○ Beta adrenergic blocking agents
What are Important side effects of benzodiazepines?
§ Confusion
§ Anterograde amnesia
