1B: psychopharm of alcohol cont.

If a tolerance for alcohol is reached what might be cross-tolerated

Barbiturates & bendiazepines in the sedative-hypnotic class

Acute tolerance

Occurs within a single exposure to alcohol

Drug effects are greater when BA alcohol is rising and smaller when BA level is falling

Metabolic tolerance

Tolerance for enzymes so increase in liver enzyme causes alcohol to be metabolized faster

Pharmacodynamic tolerance

Neurons adapt by changing cell function

Behavioral tolerance

Practicing behaviors while under the influence of alcohol allows adjustment

• classical conditioning may have a role

• less evidence not in the novel environment

Prolonged use

Produces physical dependence

• intensity & duration of withdrawal signs are dependent on amount & duration of drug taking

• Hangovers may be a withdrawal or sign of acute toxicity

Classic withdrawal symptoms of alcohol

Increase in BP and hr, nausea, sweating, tremors

Some alcoholics experience DT (delirium tremors) which include convulsions and hallucinations

What is the legal limit and at what limit does it impact accidents

.08 is the legal limit, at .05 it greatly increases the risk of accidents

Lethal limit and unconscious limit

.45% is lethal

.35 is unconscious

Death results from depression of respiratory control center in the brain