Neurology 342 - CNS Depressants: Inhalants

reduce activity in the brain

What do CNS depressants do?

calm anxiety

What do sedatives do?

induce sleep

What do hypnotics do?

GABA receptors

Which neurotransmitter is the main target in CNS depressants?

ionotropic

- Cl- into the cell

- positive allosteric modulators

What do GABA A receptors do?

metabotropic

- K+ out the cell

What do GABA B receptors do?

- inhalants

- alcohol

- barbiturates

- benzodiazepines

What are different types of depressants?

any breathable chemical that alters cognitive function

What are inhalants?

- volatile solvents

- gases

- aerosols

- nitrates

Name some examples of different inhalant types?

teen ands pre teens

What age group is the most common to use inhalants?

- sniffing

- spraying

- huffing

- bagging

- inhaling

In the pharmacokinetics of inhalation name the different ways of administration?

direct inhalation vapors

How is sniffing administered?

dispense from a spray can directly into mouth

How is spraying administered?

huffing

Which type of inhalation administration refers to breathing vapors from solvent soaked rag?

bagging

Which type of inhalation administration refers to placing compounds in a bag and breathing the fumes?

filling balloon with nitrous oxide and breathing it in

How is inhaling administered?

- inhibit action potentials

- positive GABA A receptor modulator

- NMDA receptor antagonists

What are characteristics of inhalant pharmacodynamics?

white matter atrophy

What are effects on the brain caused by inhalants?

- cerebral cortex

- cerebellum

- optic nerve

Which brain regions are effected from white matter atrophy?

user goes into sudden cardiac arrest after use of inhalant

Explain sudden sniffing death syndrome?

- excitation

- anxiolysis

- euphoria

In stage 1 of inhalant intoxication what are the elements of it?

- slurred speech

- visual problems

- early CNS depression

In stage 2 of inhalant intoxication what are the elements of it?

- medium CNS depression

- confusion and deleroum

- motor incoordination

In stage 3 of inhalant intoxication what are the elements of it?

- late CNS depression

- confusion and stupor

- seizures

In stage 4 of inhalant intoxication what are the elements of it?

chemical found in paint thinner, nail polish, spray paint

- most commonly abused solvent

What is toluene?

huffing and bagging

The most common ways of administrating toluene are?

Fat soluble

- cross the BBB and placenta barriers

How is toluene distributed?

cause fetal solvent syndrome

If toluene is used bye a pregnant women, what can this do to the fetus?

smaller heads, thin upper lips

- growth delays and language impairment

What is fetal solvent syndrome(FSS)?

as hippuric acid

How is toluene excreted in urine?

25 minutes

What is the elimination half life of toluene in breath?

0.5 to 3 days

What is the elimination half life of tool from fat tissue?

- anxiolytic properties

- anticonvulsant effect

- biphasic locomotor response

List the reinforcing effects of toluene

- increase activity at low conc.

- decrease activity at high conc.

What is a biphasic locomotor response?

- impaired learning

- impaired short term and long term memory

What are some detrimental effects of toluene?

Dopamine, in the VTA

toluene stimulates firing of which neuron in the __________?

function and expression of GABA A is reduced

After chronic use of toluene what happens to GABA A receptors?

NMDA

Which neurotransmitter receptor is enhanced after chronic use of toluene?

cerebral, cerebellar, and brainstem

neurological symptoms such as apathy and inattention in chronic toluene user found atrophy in what brain structures?

enlargement of ventricles

neurological symptoms such as memory impairment in chronic toluene user found enlargements where in the brain?

eyes make repetitive and uncontrolled movements

What is nystagmus?

- nitrous oxide

- ether

- chloroform

What are some examples of anesthetic inhalants?

rapid and short lived

- temporary loss of motor control dissociative psychological effect

What are the effects of anesthetic inhalants?

sniffing and spraying

What are the types of administration used for nitrous oxide?

respiratory system

- rapid onset

Where is nitrous oxide absorbed?

not stored in tissue

- BBB permeable

- travel through bloodstream

How is nitrous oxide distributed?

~ 5 minutes

What is the elimination half life of nitrous oxide?

- NMDA receptor antagonist

- GABA A receptor activation

What are the anxiolytic actions of nitrous oxide?

activates neurons with opioid receptors in pain areas

What the analgesic actions of nitrous oxide?

- euphoria

- relaxation

- sound distortion

What are the acute effects of nitrous oxide?

- Vit. B12 deficiency

- paresthesia

- bone marrow, heart, lung, and liver damage

What are the chronic effects of nitrous oxide?

tingling or numbness in fingers and toes

What is paresthesia?

hyperpigmentation of extremities

What is a rare side effect of vitamin B12 deficiency that is sometimes seen with nitrous oxide abuse?