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a name that specifies a particular chemical but not a particular brand

Provigil (modafinil)

a medication used to treat narcolepsy, shift work sleep disorder, and daytime sleepiness associated with sleep apnea

Nuvigil (armodafinil)

a longer-lasting version of modafinil, approved to treat the same conditions


an inactive drug

double-blind procedure

experiment in which neither the doctor nor the patient knows which drug is being used

dose-response curve

a graph comparing the size of response to the amount of drug


uncoordinated walking


unconscious and unable to be aroused

ED 50

effective dose for half of the animals tested

LD 50

lethal dose for half of the animals tested

therapeutic index (TI)

ratio of LD 50 to ED 50

safety margin

dosage difference between an acceptable level of effectiveness and the lowest toxic dose

side effects

unintended effects that accompany therapeutic effects


measured by the amount of drug required to produce an effect

time course

timing of the onset, duration, and termination of a drug's effect

cumulative effects

effects of giving multiple doses of the same drug

lipid solubility

tendency of a chemical to dissolve in fat, as opposed to water


injection directly into a vein


injection under the skin


injection into a muscle


product of enzyme action on a drug

active metabolites

metabolites that have drug actions of their own


drugs that are inactive until acted on by enzymes in the body

drug disposition tolerance

tolerance caused by more rapid elimination of the drug

behavioral tolerance

tolerance caused by learned adaptation to the drug

pharmacodynamic tolerance

tolerance caused by altered nervous system sensitivity

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