alcohol study guide Flashcards
pharmacokinetics
- readily mixes with water and is soluble in fat
- easily absorbed from GI tract, diffuses throughout the body, readily enters most tissues, including brain (BBB)
**time from last drink to maximal absorption in blood is ~60 mins
absorption and distribution
- rate of absorption extremely variable, for this reason, behavioral effects are described based on blood alcohol concentration (BAC) rather than on the amount ingested
- it would take an adult about an hour to metabolize the amount of alcohol that is contained in a 1 oz. glass of whiskey, 3.5 oz. of wine, or 12 oz. beer
- in general, it takes BAC of .04% to produce measurable behavioral effects
- easily absorbed from the GI tract and diffuses throughout the body: 20% from stomach and 80% from upper intestines (move across membrane barriers by passive diffusion)
gender differences
- one beer is much more concentrated in the average woman compared to a man because:
- on average, males have greater vascular capacity: the larger the individual, drug more diluted
- men are larger than women; have greater fluid volume
- gastric metabolism of alcohol ~50-60% more active in males than females
- females: higher concentrations of alcohol that will be more rapidly absorbed
- when drinking same weight-adjusted amounts of alcohol: women ~7% high BAC than male
- women with higher body fat than men concentrate alcohol in plasma, drink for drink, more than men, raising the apparent blood level
alcohol dehydrogenase
found in stomach, reduces amount of available alcohol for absorption
alcohol-related accidents
binge drinking
- 5+ drinks on the same occasion on at least 1 day in the past 30 days (for men)
- 4+ drinks for women
alcohol metabolism (pathways)/ CYP450
role of area postrema
blood monitoring system
- alcohol is very toxic
- concentration between .12 - .16 induces vomiting - especially with rapid drinking
- AP activation makes it harder to get lethal dose - will vomit first
vomiting area basically
acute tolerance
occurs with a single exposure to alcohol
drug disposition tolerance
increased enzyme activity = more rapid metabolism = less drug
pharmacodynamic tolerance
neuronal adaptation
behavioral tolerance
learn to adapt behaviors when allowed to practice while under the influence
pharmacodynamics: chronic effects
pharmacodynamics: Alcohol-Glutamate
pharmacodynamics: Alcohol-GABA
pharmacodynamics: Alcohol-Dopamine
Alcoholism
co-morbidity
alcohol pharmacotherapy
benzodiazepines
- increase GABA activity
- ameliorate withdrawal symptoms; prevent seizures and DTs
- long-acting, prevent withdrawal symptoms (either maintained or slowly withdrawn) allowing person to function
Drawbacks: sedation psychomotor deficits additive interactions with alcohol abuse and dependence liabilities
anticonvulsants mood stabilizers
campral/anticraving drugs
disulfiram
heavy use
five or more drinks on the same occasion on at least 5 different days in the past 30 days
psychological effects
- feels relaxed and less anxious
- may feel somewhat sleepy
- relaxed state is demonstrated by reduced social inhibition more gregarious, talkative, and friendly or inappropriately outspoken
- self-perception and judgement somewhat impaired, more confident than reality proves true
- reduced judgement and induce overconfidence increased risk-taking and may make sexual encounters more likely
CNS-related effects
low dose:
- deficits are based more on expectation than on quantity consumed
- under high-stress conditions, it enhances performance by minimizing anxiety
high dose:
- may cause amnesia for the events occurred during intoxication even though individual behaved quite normally
blackout
common occurrence for alcoholics; occurs in 25% of social drinks
alcohol poisoning
unconsciousness, vomiting, slow and irregular breathing and skin that is cold, clammy, and pale bluish in color
when death occurs
due to depression of respiratory control center in the brain stem.
once respiratory mechanism is compromised the drinker can survive for 5 minutes but brain damage from oxygen deprivation occurs
