Drug Schedules
Drug Schedules
Goal: to organize the control of drugs under 5
classifications (schedules of controlled substances)
 Potential for abuse
 Accepted medical use
 Schedule 1: High potential for abuse; no accepted
medical use (LSD)
 Schedule II: High potential for abuse; Some accepted
medical use (cocaine)
 Schedule III: Some potential for abuse; accepted
medical use (mixtures-1.8%codeine)
 Schedule IV: Low potential for abuse; accepted medical
use (valium)
 Schedule V: Minimal abuse potential; widespread
medical use (laxatives)
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Toxicity:
 -Poisonous, deadly, or dangerous
 -Effects of drugs that interfere with normal functioning
 Acute Effects: result from a single administration of a
drug; the drug is present in the system
 Chronic Effects: Result from long-term exposure
 Onset of action; duration of the effect:
 The faster the onset (when a person starts to feel the
effects) & the shorter the duration (effect of drug lasts a
short period), the more likely the person will become
physically dependent on the drug (depressants).
 In other words, the faster the absorption, the more
intense the high; but the faster the absorption, the
shorter the duration.
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Physical dependence: When a person begins to
experience withdrawal symptoms after the drug is
taken away. Bodies need to constantly have the
drug or drugs.
Physical dependence depends on:
-how quickly the drug enter the brain
-how quickly the drug leaves the system
Intense physical dependence:
Barbiturates (grouped on the basis of the
duration of their activity)
◦ Short acting- (15 min. onset; 2-3 hour duration) most
likely to be abused.
◦ Intermediate acting (30 min. onset; 5-6 hour duration)
◦ Long-acting (1 hour onset; 6-10 hour duration)
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Psychological dependence is the mental inability
to stop using the drug.
Some Facts:
*Alcohol (most widely used depressant)
*Narcotics (heroin)-b/c most potent
& other CNS depressants
*Sedatives are most widely prescribed depressant.
Potency of Opiates:
Potency-amount of drug necessary to cause an effect.
The smaller the dose required to achieve a drug
action, the greater the potency.
*Morphine is 10X stronger than raw opium.
*Heroin is 3X as potent as morphine (accounts
for 95% of all recreational narcotic use in U.S.)
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Other Factors that Determine Drug
Effects
Non-specific Effects: The effect of the drug
does not depend solely on chemical interactions
Influences of expectancy, experience, & setting
can also help determine the drug’s effect.
Weight, Age, & health status also influence the
effects a drug will have.
When 2 or more drugs are taken together, their
interaction can alter the effects of the drugs,
counteract the effects of one or more of the
drugs, or increase the effects.
Dose-response Relationship: The size
of the effect changes directly with the
drug dose
 *Increasing the dose of the drug will
not always increase the magnitude
of the effect.
 Time-Dependent Factors in Drug
Actions:
 -How the drug was administered
 -How rapidly it was absorbed
 -How it is eliminated from the body
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Methods of Administration: To produce
an effect, a drug has to enter the body.
 1. Orally: By mouth; the most common
way of taking a drug is by swallowing it.
 Advantages:
 Easy to use
 Painless
 Disadvantages:
 Complicated way to enter bloodstream
 Deactivated by food/bile
 Metabolized by liver
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2. Injection-IV: Some drugs are injected
using a syringe & needle. A drug that is
injected goes directly under the skin into a
blood vessel. Drugs must be in liquid form
to be injected into the body.
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Advantages:
 Directly into blood
 Rapid results
 Deliver high concentration
 Irritating material can be administered
 Disadvantages:
 Vein walls lose strength
 Introduce infection & disease
 Needle phobia
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3. Injection-intramuscular: Injected
using a syringe & needle, into the
muscle
 Advantages:
 Rapid absorption
 Large volume of drug
 Disadvantages:
 Tissue irritation
 Pain (for some)
 Needle phobia
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4. Inhalation: Some drugs are inhaled
through the nose or mouth and enter the
bloodstream through the lungs.
 Advantages:
 Very rapid absorption (5-8 seconds)
 Very accessible to lungs
 Disadvantages:
 Irritate mucous membranes of lungs
 Dosage difficult to control
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5. Topical: A drug that is absorbed enters the
bloodstream through the skin or mucous
membranes. Ointments, creams, lotions, sprays, &
patches contain drugs that are absorbed.
(cocaine)
Advantages:
Slow, steady absorption
Disadvantages:
Not absorbed well thru skin
*Some drugs are also implanted, or placed under
the skin where they can be released into the
bloodstream. For example, some forms of cancer
therapy involve implanting drugs under the skin