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Alcohol & College Life
Pharmacology
By the end of this lesson, you will be able to:
• Recognize differences among the various classes of drugs, including
depressants, stimulants, and hallucinogens;
• Identify the five principles of drug action;
• Recognize the relationship between how a drug is administered, its effects
and the probability of dependence;
• Correlate levels of blood alcohol content with specific physical effects;
• Identify research pertaining to drug and alcohol affects on adolescent
brains; and
• Describe how alcohol affects women differently than men.
It is important to have a basic understanding of the effects drugs have
on your body.
Pharmacology is the study of how drugs interact
with and work in the human body.
There are different classifications of drugs. Some
drugs slow you down, others speed you up. Still
other drugs cause you to view your environment
from a different perspective.
Drugs that slow us down are called depressants.
Major depressants include alcohol, sleeping pills, GHB, and tranquilizers such as
Valium, Librium and Rohypnol, as well as narcotics such as opium, morphine and
heroin, oxycontin (oxycodone), fentanyl, and hydrocodone.
Depressants work by slowing down vital central nervous system functions. These
include areas of the brain that control heart rate and breathing, as well as motor
control and inhibitions.
As dosages increase, heart rate and breathing both decrease. In fatal doses, the
heart and lungs slow down to a point that oxygenated blood is no longer sent to
the brain, and the person dies.
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Drugs that speed us up are called stimulants.
Stimulants include caffeine, nicotine, cocaine, and amphetamines like Adderall,
Ritalin, and methamphetamine.
Stimulants excite the central nervous system. In small doses, they make us more
alert and increase heart rate and breathing. High doses of stimulants greatly
increase feelings of paranoia. Overdoses of these drugs tend to lead to heart
attacks or strokes.
Hallucinogens are drugs that cause people to view their environment from a
different perspective.
These include LSD, peyote, PCP, mescaline and some poisonous mushrooms.
Hallucinogens change the way the brain interprets information. One aspect of this
is "synesthesia," or sensory crossing. One can "see" music coming out of a speaker,
for example, or "taste" a color on the wall.
Hallucinogens are usually taken in small doses, minimizing the chance of a physical
overdose. For example, if a pill the size of an aspirin tablet were pure LSD, it would
be the equivalent of 30,000 doses. LSD is an odorless, tasteless liquid that is usually
absorbed from tiny pieces of blotter paper placed in the mouth.
If you've heard of people taking LSD in pill form, you can be sure the pill isn't all LSD.
It’s important to consider the purity of a drug. Hallucinogens are often mixed with
other drugs that can have more serious physical consequences.
Generally, most drugs fit into one of these three categories: depressants, stimulants,
or hallucinogens.
However, marijuana and ecstasy are two drugs that can each be placed in their
own categories. Both drugs have unique characteristics that set them apart from
the others.
Marijuana is often classed under "hallucinogens,"
but it actually interacts with the body quite
differently.
In very high doses, marijuana can cause
hallucinations, but it is mainly used as a mild
intoxicant or euphoric. When someone is smoking
pot, she may experience a relaxed feeling (a
common effect of depressant drugs), an
increased heart rate and blood pressure (a
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common effect of stimulant drugs), and some sensory impairment (a common
effect of hallucinogenic drugs); thus, marijuana does not neatly fit into any of these
categories.
MDMA, or ecstasy, is often considered a stimulant with hallucinogenic properties
because it is a derivative of a methamphetamine.
However, it differs from other methamphetamines in that it produces an
empathetic response towards others. In fact, ecstasy is often called the “love drug”
or “hug drug.”
Ecstasy is not physically addictive but people can become emotionally or mentally
dependent on it, and face other dangerous consequences as a result of using it
including depression and exhaustion. Research also shows that long-term
neurotoxic effects of ecstasy use may exist, including effects on memory, mood,
impulsivity, logical reasoning, and calculation.
In order to understand a drug's effects, several principles of drug pharmacology
come into play, including:
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potency,
purity,
tolerance,
cross-tolerance, and
possible interactions with other drugs.
The dose, or how much of a drug is taken, is obviously an important variable in a
drug reaction.
There's a substantial difference between one glass of beer and a case of beer.
The strength, or potency, of a drug is also important.
Drinking a pint of 3.2% beer -- which equals 6.4 proof -- is different from drinking a
pint of 80-proof vodka -- which could probably kill you.
"Proof" represents twice the percentage
of alcohol content. For example, 80proof liquor is 40% alcohol. Both doses
are a pint of alcohol, but the 80-proof
vodka is much more potent than the 3.2
beer. This is taken into account when we
consider “standard drink” sizes.
An overdose is much more likely when
the potency of the drug taken is very
high. Overdose is also likely when the potency of a drug is unknown. For example,
Image by: Gergerger7 @ sxc.hu
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the potency of heroin can be anywhere between 30-40%; the problem is that the
user often has no way of knowing the true potency of the drug being taken.
Most street drugs are impure. They are mixed with other substances such as sugar or
baking soda in order to increase profits. In the case of heroin, some "overdose"
deaths are, in fact, allergic reactions to contaminants. Remember, there is no
"Good Housekeeping" seal of approval on street drugs. You never really know what,
or how much, you are getting. Keep in mind that as purity increases, potency
increases, as does the risk of overdose and other adverse effects.
Having a high tolerance to a drug is nothing to brag about; it is a sign that your
body is being changed by a drug – and not necessarily in a good way.
Tolerance is the body's capacity to become less sensitive to the same dose of a
substance as a result of its repeated use. A person who uses regularly eventually
needs a larger amount of the drug to produce the same effect. While the high
produced with the same dose may diminish, however, the toxic effects to the brain
and liver cells remain the same.
Tolerance increases quickly with stimulants such as caffeine, amphetamines,
cocaine and true narcotics. With alcohol, this doesn't happen as quickly.
If you use and become tolerant to a drug, you will probably also be tolerant to
other drugs within that same category. This is referred to as cross-tolerance.
For example, alcohol and anesthesia are both depressants. If you drink a large
amount of alcohol -- more than twelve drinks per week -- you will probably require
more anesthesia while undergoing surgery. When doctors ask about your alcohol
use, they usually have a good reason. If you are going into surgery it is important to
be honest about how much you drink. You wouldn't want to regret lying to your
doctor half-way through an appendectomy!
The principles of drug actions are very useful in determining the effects of a single
drug. However, in the real world, people seldom use just one drug at a time. The
next time you are at a party, look around. Do you see anyone smoking a cigarette
and drinking?
Your body's reaction to a certain drug may be affected by other drugs in your
system.
Someone who took Tylenol before a party, drank a couple of beers and smoked a
few cigarettes is not being affected by the beer alone. What most people don't
realize is that each of these three drugs has its own effect. Combined, they may
interact unpredictably.
Take note: Mixing alcohol and acetaminophen (sold under the brand name
Tylenol), is very harmful to the liver and could lead to death.
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Mixing alcohol with other drugs is common, even though it is ignored in many harm
reduction and drug education programs. Keep in mind, when you mix drugs and
alcohol, you are increasing your risk of problems. One drug might increase the
effects of another - sometimes lethally. Most drug interactions are highly
unpredictable and therefore inherently dangerous.
Effects can occur at many different levels, ranging from increasing a drug's toxicity
to changing a person's behavior in a dangerous way. The best advice we can give
you on this subject is the simplest: DON'T DRINK AND DRUG!
Over the Counter Drugs and Drinking
Video Transcript
Christine: I just know from experience that you aren't supposed to take ibuprofen or
other drugs that thin your blood before drinking or while drinking. And so, if I'm
sore or I need to be using ibuprofen or something like that, I just make sure it's
plenty of time before I'm drinking or I just don't drink.
Liz: So, freshmen year, my roommate and I were both pretty sick. Um, we got what
was going around everywhere, living in the dorms. You're kind of bound to get
sick because you're so close to everybody. And we had taken some cold
medicine about an hour before we started drinking. After about 3 beers, I
noticed that I was absolutely wasted. It was just this state of drunk that I would
never want to be in again. I just didn't feel in control at all and it just kind of
taught me never do that and to always be careful of what I'm taking and how
it's going to react, if I drink that night with alcohol.
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The way you take a drug can influence the probability that you will become
dependent on that drug.
For example, drinking coffee has less potential for dependence than injecting
coffee would have. Dependence is related to how fast a drug reaches the brain,
and with what degree of impact. A drug that reaches the brain quickly with a high
degree of impact will be more likely to create dependence. This is the reason why
smoking tobacco is more addictive than chewing it and smoking crack is more
addictive than snorting cocaine.
The way you take a drug can also impact your potential of suffering an overdose.
For instance, a person is much more likely to overdose on injected narcotics, rather
than ingested (swallowed) narcotics. However, using these drugs in any way
without a doctor’s prescription and supervision is not a good idea!
Keep in mind that when a drug is made illegal by the government, there is no
longer any way to control the purity and potency of that drug.
Additionally, it’s also good to remember that if a person uses a prescription drug for
something other than its intended medical use, the effects can be highly
unpredictable.
There is no stamp of approval by the Food and Drug Administration for a drug that
is bought on the street. There is no way of knowing the ingredients of a street drug.
These drugs will vary in their purity and potency, making illegal drug use very risky in
more than one way.
When making decisions about alcohol and drugs, always remember the mantra of
every pharmacologist: "Every drug has two effects -- the one I know about and the
one I don't know about."
The Drug Enforcement Administration (DEA) publication Drugs of Abuse is a reliable
resource on the most popularly abused drugs, both legal and otherwise. It offers
straightforward yet scientific information about drugs you might be curious about.
Drugs of Abuse
Please return to page 19 of the online lessons or visit the link directly to
review by the U.S. Department of Justice Drug Enforcement
Administration’s pamphlet on Drugs of Abuse:
http://www.justice.gov/dea/docs/drugs_of_abuse_2011.pdf
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Alcohol is the most commonly used intoxicant in the world.
After a drink or two, complex functions of the brain begin to slow down. Inhibitions
lower. These toxic effects of alcohol on the brain are often interpreted as an
altered state of consciousness, known as intoxication.
At first, people might feel excited and
happy when they drink. This is why many
people think alcohol is a stimulant. People
might say and do things that they normally
wouldn't. Their common sense seems to
fade away.
After a few more drinks, deeper levels of
the brain are affected. Speech becomes
slurred. Walking becomes difficult. For most
people, their upper lip gets numb. Beyond
this point, any more alcohol can affect the parts of the brain that control breathing
and heart rate. This response is dose-related. That means, that the more you drink,
the more alcohol depresses your vital functions.
Most people do not realize that the feelings they get from drinking are actually
toxic effects.
But toxic effects, such as decreased heart rate and slower breathing, are not what
people are seeking.
They drink because they like the feeling of intoxication. This feeling is comfortable
for some but not others.
Drinking alcohol is one of many ways people alter their consciousness. Intoxication
provides a short "vacation" from everyday feelings. Some people seek this state to
the point of dependency, while others enjoy brief episodes that do not become a
central feature of their lives. Still others dislike the feeling of being even slightly "out
of control."
Until the 1990's, there were almost no studies on how alcohol affects the adolescent
brain.
Most scientists simply thought of adolescent brains as smaller adult brains.
The National Institute of Alcohol Abuse and Alcoholism is sponsoring research on
rats, mice and monkeys, which is showing that alcohol affects the brains of
adolescents in far different ways than it affects adult brains. Additionally, the
American Medical Association recently released a report titled "Harmful
Consequences of Alcohol Use on the Brains of Children, Adolescents, and College
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Students." The research discussed in this report supports the notion that alcohol can
damage the developing brain, especially the hippocampus and the frontal lobe. 24
To understand this research, two terms must be understood: "adolescence" and
"hippocampus."
From an experimental standpoint,
"adolescence" is a life stage determined by
comparing both average life spans and
physical characteristics of maturity in
experimental animals vs. similar markers in
humans. Scientists were able to find a period
in the life span of the animals that
correspond roughly with teenage years in
humans.
The "hippocampus" is an area of the brain
where new knowledge is temporarily stored until it is permanently filed, days to
weeks later.
So what happened? It appears that even moderate amounts of alcohol have
more of an effect on an adolescent's hippocampus than on an adult's. Alcohol use
decreases the ability of the hippocampus to acquire and remember new
information.
This is important, because the adolescent brain is importing more new information
every day, particularly in the area of social skills. Some new information may not be
acquired by the hippocampus when the animal consumes alcohol. It could be
misfiled or lost before it is permanently filed. It is quite probable that these same
effects occur in the brains of adolescent humans who drink alcohol as well.
Obviously, this can have a huge effect on a teen’s ability to learn new information
– a critical skill for any student!
A behavioral study of monkeys showed dramatic results. Adolescent male monkeys
are raised by their mothers until they learn enough social skills to join the larger tribe.
In one study, adolescent male monkeys were allowed to consume moderate
amounts of alcohol when they were under their mother's care. When scientists
allowed these monkeys to join the larger tribe, the older male monkeys killed them.
Apparently, they had not fully learned the necessary social skills, and were
perceived as a threat to the older males.
Human adolescents in chemical dependency treatment programs have shown
similar social developmental lags. Young people who were frequently "stoned" or
drunk in their early teens lack age-appropriate social skills as adults. Counselors
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generally have to educate them on the social skills they failed to learn while they
were using.
The effects of alcohol are determined by the amount of alcohol in the
bloodstream.
Alcohol is the only drug where blood levels of alcohol are correlated with specific
physical effects. The more a person drinks, the higher the concentration of alcohol
in his or her blood will be. The higher someone's blood alcohol concentration is, the
more drunk he or she will feel, and the more drastic the changes in his or her
behavior will be.
The Virtual Bar is a tool intended to illustrate the impact of different drinks on a
drinker's BAC. In order to interact with the tool on the following page, you must
enter an age of at least 21 for your fictional drinker, in addition to other details
including weight and height. It also allows you to manipulate other factors such as
time and food consumption to see how BAC can be affected. As you interact with
the tool, note the "time until 0" indicator. Consider how heavy alcohol use could
result in an elevated BAC the morning after. Some drinkers might need to think
twice about jumping in the car and heading to work the morning after a party.
Virtual Bar
Please return to page 27 of the online lessons or visit the link directly to
visit a virtual bar to assess the impact drinking has on your blood
alcohol level: http://www.b4udrink.org/virtual-bar
Alcohol is the one area where men and women are not created equal.
There are a few physiological differences that result in women absorbing and
metabolizing alcohol differently from men.
Women will have higher BAC's after
consuming the same amount of alcohol as
men and are more susceptible to alcoholic
liver disease, 25 heart muscle damage, 26 and
brain damage. 27 This is thought to be due to
lower amounts of body water. Additionally,
women have lower activity of the alcoholmetabolizing enzyme ADH in the stomach,
causing a larger proportion of the ingested
alcohol to reach the blood.27 The combination
of these factors may render women more
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vulnerable than men to alcohol-induced liver and heart damage. 28
Females are generally more affected by alcohol just prior to menstruation. Females
taking birth control pills or medications containing estrogen may remain intoxicated
longer than those who do not, due to the liver's function of metabolizing both. 29
So, as you learned throughout most of the lesson, properties of a drug itself (the
agent) have a large impact on a person's experience with that drug. However, as
pointed out in the previous slide, regardless of the drug, different people are likely
to have somewhat different responses based on different personal characteristics.
These are important concepts to keep in mind as you continue on your journey
throughout this course...and life in general!
Many parts of this lesson were adapted from the following publication:
Kuhn, C., Swartzwelder, S., & Wilson, W. (2008). Buzzed: The straight facts about the
most used and abused drugs. New York: W.W. Norton & Company.
Lesson content created by the Rothenberger Institute in
the School of Public Health at the University of
Minnesota. © 2014 Regents of the University of
Minnesota. All rights reserved.
The Rothenberger Institute provides a suite of wellness-based courses focusing on the
knowledge and skills students need to lead healthy, productive, and balanced lives. For
more information visit www.ri.umn.edu
American Medical Association. (2009). Harmful consequences of alcohol use on
the brains of children, adolescents, and college students. Retrieved May 30,
2013, from http://www.rwjf.org/en/research-publications/find-rwjfresearch/2009/03/harmful-consequences-of-alcohol-use-on-the-brains-ofchildren--a.html
25 Loft, S., Olesen, K., & Dossing, M. (1987). Increased susceptibility to liver disease in
relation to alcohol consumption in women. Scandinavian Journal of
Gastroenterology, 22(10), 1251-1256.
26 Urbano-Marquez, A., Estruch, R., Fernandez-Sola, J., Nicola, J., Pare, J., & Rubin, E.
(1995) The greater risk of alcoholic cardiomyopathy and myopathy in women
compared with men. JAMA 274(2), 149–154.
27 Marshall, A., Kingstone, D., Boss, M., & Morgan, M. (1983) Ethanol elimination in
males and females: Relationship to menstrual cycle and body composition.
Hepatology, 3(5), 701-706.
28 Baan, R., Straif, K., Grosse, Y., Secretan, B., El Ghissassi, F., Bouvard, V., ... &
Cogliano, V. (2007). Carcinogenicity of alcoholic beverages. The Lancet
Oncology, 8(4), 292-293.
24
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29
Sutker, P., Goist, K., King, A. (1987) Acute alcohol intoxication in women:
Relationship to dose and menstrual cycle phase. Alcoholism: Clinical and
Experimental Research 11(1), 74-79.
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