Ethanol Flashcards
Where is alcohol most rapidly absorbed?
Small Intestine
Note that a heavy meal can decrease the peak concentration by 30%…though all of the alcohol still makes it to the blood, just more slowly.
Where is alcohol distributed?
Water soluble = throughout all tissues and fluids of the body.
Crosses placenta.
More rapid in areas of high blood flow: brain, liver, kidney, lungs.
Initial CNS effects = 5 minutes.
Peak effects = 15 - 60 minutes.
More body fat = less alcohol absorbed = higher blood alcohol
Women have a lower blood alcohol level.
How is alcohol eliminated?
Metabolism: 90 - 98% of removal.
Liver is primary organ, some is expired and peed out (2 - 10%)
Women have less gastric metabolism than men, so may account for a higher BAC than men.
What is the rate of metabolism?
Zero order kinetics = constant rate.
Note, this means it always works at the same rate no matter the levels of blood alcohol.
What are the 2 enzymes that convert ethanol to acetaldehyde?
- alcohol dehydrogenase - in liver
- CYP2E1 (mixed function oxidase)
- works when BAC is high
- can contribute 10 - 25% of ethanol metabolism
What enzymes convert acetaldehyde to acetate?
Aldehyde dehydrongenase - in liver.
Anti-abuse drug disulfiram (Antabuse) inhibits aldehyde dehydrongenase.
What if metabolism is insufficient and acetaldehyde builds up?
Acidosis, Convulsions, Gout attacks Fatty liver Hypoglycemia
What affect does ethanol have on the CNS?
Acute:
Sedative-hypnotic effect.
Effects are proportional to the BAC (similar to barbiturates)
Note: NEVER a stimulant at any dose, but at low doses inhibits cortical neurons = a relative stimulatory phase.
Acts by altering neurotransmitter function.
Low doses = GABA interactions (enhancer) and glutamate NMDA (inhibits) interactions.
Is anticonvulsant, but withdrawal results in opposite.
Similar analgesia to morphine. Pain is perceived, but patient doesn’t care.
On sleep, similar to barbs, it suppresses REM.
Emetic.
Hangovers.
What affect does ethanol have on the liver?
At first damage is reversible.
Cirrhosis can occur.
Can cause esophageal varicosities.
Can result in increased bleeding time (decrease in synthesis of clotting proteins).
What affect does ethanol have on the kidney?
Diuretic effect by inhibiting antidiuretic hormone.
What affect does ethanol have on the GI tract?
Irritant to the GI tract.
If taken with aspirin, can have ulcers.
Increases digestive secretions, can result in pancreatitis.
High doses can decrease absorption.
What affect does ethanol have on the fetus?
Prenatal or postnatal growth retardation and altered morphogenesis and CNS involvement (retardation).
1st: morphologic abnormality
2nd: risk of spontaneous abortion
3rd: decreased growth
What affect does ethanol have on the heart?
Vasodilator, increases hypothermia risk.
Can damage cardiac muscle increases blood pressure.
When does withdrawal start?
When are peak symptoms of withdrawal?
When do seizures start?
When does withdrawal start: 0 - 48 hours post drink.
When are peak symptoms of withdrawal: within 24 - 36 hours.
When do seizures start: 6 - 48 hours after withdrawal starts
How is alcohol withdrawal treated?
Benzos
Clonidine (alpha 2 adrenergic agonists)
More alcohol
