CNS Depressants Flashcards
Are CNS depressant sympatholytic or sympathomimetic
Sympatholytic
Most widely used substance of abuse
Alcohol
Medical uses of ethanol
Relief long lasting pain
Methyl alcohol and ethylene glycol poisoning
Disinfectant or antiseptic
Solvent
How is alcohol used to treat long lasting pain
Epidural, subarachnoid and lumbar paravertebral injections of ethanol destroys sympathetic ganglia and produce vasodilation and relieve pain
Which enzymes metabolize alcohol
Alcohol dehydrogenase
Aldehyde dehydrogenase
Mixed function microsomal oxidase (Cytochrome p450 2E1) or Microsomal Ethanol Oxidising Systems (MEOS)
Explain the biphasic activity of ethanol
Preferential suppression of inhibitory neurons followed by
Global inhibition of all CNS Neurons
Which receptors or pathways does alcohol affect
Enhance GABA and Glycine inhibition
Inhibit VG Ça channels
Activates K channels
Inhibits ionotropic Glutamate receptors
Inhibits adenosine transport
Effects of alcohol diuresis
Dehydration
Thirst
Lightheadedness
How does alcohol trigger an inflammatory response
Direct toxicity of acetaldehyde and alcohol on neurons
Effects of alcohol on glucose metabolism
Causes hypoglycemia by inhibiting gluconeogenesis
Effects of alcohol on vascular smooth muscle
Alcohol and acetaldehyde causes vasodilation
Effects of alcohol on gastric mucosa
Irritates lining of stomach and stimulates acid secretion
Why is acetaminophen avoided in managing alcohol abuse
It can exacerbate hepatotoxicity
Which drugs are used to alleviate acute symptoms of alcohol withdrawal
Benzodiazepines
Propranolol
Clonidine
Drugs to reduce alcohol craving
Naltrexone
Nalmefene
Baclofen
Acamprosate
Drugs to maintain remission in alcoholism
Topiramate
Acamprosate
Which fluid is used to replace potassium in hospitalized alcoholics
Ringers lactate
Which antacids are preferred to manage stomach upset in alcoholics
Aluminium based antacids are preferred over magnesium based antacids
Mild to moderate symptoms of alcohol withdrawal
Sweats
Tachycardia
Tremors
Insomnia
Anxiety
Psychomotor agitation
Severe symptoms of alcohol withdrawal
Generalised tonic clonic seizures
Delirium tremens
Hallucinations
Which receptors mediate alcohol withdrawal symptoms
GABA receptors
NMDA receptors
Which benzodiazepines are preferred in alcohol withdrawal
Longer acting ones
Chlordiazepoxide
Clorazepate
Diazepam
Why are longer acting benzodiazepines preferred in alcohol withdrawal
Easier weaning because they usually self taper on metabolism and excretion, leading to less fluctuations in plasma drug levels
They cause fewer rebours effects and withdrawal seizures
When are short acting benzodiazepines used in alcohol withdrawal
For alcoholics with liver disease and the elderly
Examples of short acting benzodiazepines
Lorazepam
Oxazepam
Temazepam
Role of thiamine and other vitamins in managing alcoholism
To increase glucose utilization by the brain
Role of antipsychotics in alcoholism management
To manage hallucinations and severe agitation
Examples of antipsychotics used in alcohol withdrawal
Haloperidol
Quetiapine