Most of the drugs that people abuse have their effect on the limbic system of the brain. The limbic system is located deep within the brain near the top of the brain stem. The limbic system produces the feelings of pleasure, pain, anger, and fear which characterize our emotions. All drugs of addiction work on our emotions. If a certain drug makes us feel very good, we tend to want to take that drug again and again. It is because of this temporary good feeling that we become psychologically addicted to a drug.
Within the limbic system, drugs work on the brain by way of neurotransmitters. Neurotransmitters are the chemicals which allow our nerve cells to communicate with each other. Some of the neurotransmitters affected by drugs are serotonin, norepinephrine and dopamine. The class of drugs called stimulant drugs will usually make more a neurotransmitter(s) available to the brain. The class known as depressant drugs will usually make less of a neurotransmitter(s) available to the brain. Because our brain adjusts to this alteration in neurotransmitters, our brain may become physiologically (physically) dependent on some drugs. Although our brain can become physiologically dependent on a wide variety of drugs, the brain is more likely to become dependent on depressant drugs than on stimulant drugs.
As drugs appear in nature they can be addictive. However, it is technology which makes them very addictive. Opium, a drug which occurs naturally in the white poppy plant, is classed as a narcotic. A narcotic drug relieves pain and induces sleep. The brain has neurotransmitters which controls our perception of pain. These neurotransmitters are called endorphins. Within the brain, endorphins mask pain and make us feel good. All opium products are chemically similar to endorphins and have their pleasurable effects by substituting for endorphins in our brain.
Opium has been used and abused since the beginning of recorded history. There is a reference to opium in Homer's Odyssey written in the sixth century BCE. People have for centuries eaten and smoked opium. Some of these people became addicted to it, others did not. However, in the mid 1800's, opium was refined into morphine and codeine. Morphine and codeine magnified the power of opium ten times. Also in the mid 1800's, the hypodermic needle was invented. If the hypodermic needle is used to intravenously inject morphine, it magnifies the power of the drug 10-15 times.
In 1896 opium was further refined into diacetylmorphine, which became known as
heroin. It was named heroin because they thought it was a "hero" drug. It was
believed to be nonaddictive, and for years was a treatment for alcoholism.
Alcoholics were advised to stop drinking and substitute heroin use instead. This
was reasonably good therapy because heroin is not as damaging to the physical body
as is alcohol. However, it is far more addictive and damaging to the mind. When
the hypodermic needle is used to intravenously inject heroin, addiction develops
quickly.
Heroin is a drug to which people become both psychologically and physiologically (physically) dependent. It is a drug of escape. When heroin is intravenously injected, called mainlining, it creates a rush of excitement followed by a peaceful, calm euphoria. Heroin becomes the only thing of importance to the addict. Family, friends and work all become secondary to heroin. Since addiction to heroin makes it difficult to hold a job, crime becomes the primary way to buy heroin. Heroin addicts often become shoplifters, prostitutes and drug dealers. Heroin produces good feelings which normal living cannot match. Once the drug user experiences these great feelings of euphoria, normal feelings lose their value.
If a person must withdraw from heroin, physical dependence causes severe
withdrawal symptoms. Withdrawal begins 6-12 hours following their last injection,
and withdrawal symptoms include: weakness, nervousness, sweating, insomnia,
shaking, convulsions, hallucinations, vomiting, diarrhea, and an involuntary
movement of the arms and legs. It is from this involuntary movement of the legs
that came the expression "kicking the habit." Since withdrawal from heroin can
result in death, it is best to withdraw with medical help. Physicians can
administer an anti-seizure medication called Dilantin to reduce seizures, and an
anti-anxiety agent (tranquilizer) such as Librium to calm the nervousness and
shakes.
One treatment for heroin addiction is know as Methadon Maintenance. Methadon is a drug which is substituted for heroin. Although methadon is addictive, it is legal, cheap and not as devastating to the mind. Another drug that is useful in treating heroin addiction is Naltrexone (Narcan). Naltrexone blocks the action of heroin in the brain, so that if the addict takes Naltrexone, an injection of heroin will have no effect.
Since Heroin is a drug of escape, those who tend to become addicted to it need escape. Those who do not want escape tend not to like heroin and, therefore, do not become addicted to it. During the Vietnam war, many American soldiers used heroin daily. The war caused a need for escape. However, when they came home from Vietnam, most stopped using heroin altogether. However, in the person who psychologically needs escape, heroin addiction is very difficult to break.
Cocaine comes from the leaves of the coca plant. Like opium, technology made these leaves become very addictive. Laborers in South America pick a few coca leaves and chew them in the morning to give them a lift. They use coca leaves like we use coffee. Used in this way, coca leaves seldom cause a dangerous or damaging addiction. However, when technology is used to extract cocaine hydrochloride from the leaves, and when technology is used to covert cocaine hydrochloride into free base (crack), it becomes very addictive. Cocaine can be sniffed through the nose (snorted), injected intravenously, or converted into a free base solid and smoked (crack).
Cocaine is a stimulant drug which creates good feelings by increasing the supply of the neurotransmitter dopamine in the limbic system of the brain. Cocaine use creates feelings of great pleasure, energy, self-esteem, self-confidence, and invincibility. It depresses appetite, increases heart rate and raises blood pressure. While physical dependence to cocaine is small, psychological dependence is great.
Cocaine use has a long history in America. At the turn of the century cocaine was an ingredient in soft drinks such as Coca Cola and Dr. Pepper. It is from this that Coca Cola got it name, as well as its nickname "Coke."
Because cocaine works by stimulating pleasure circuits of the limbic system which use dopamine as a transmitter, the brain reads this extra dopamine as "too much" and shuts down the natural production of this neurotransmitter. When some people stop cocaine use, the brain soon increases its production of dopamine to near previous levels. However, in other people the brain never resumes normal production in dopamine, and the person has a permanent disability to experience normal emotional pleasure. Because cocaine increases heart rate and blood pressure, it can cause miniature, and even full blown strokes. A stroke occurs when a blood vessel in the brain bursts, and nerve cells which depended upon this vessel for blood die.
Paranoid schizophrenia is a mental illness characterized by disordered thinking, which is often accompanied by delusions and hallucinations. Paranoid schizophrenia is believed to represent too much, or an over-sensitivity to the neurotransmitter dopamine. Since cocaine abuse causes there to be too much dopamine in the brain, cocaine addicts sometimes develop paranoid schizophrenic-like symptoms. These usually take the form of delusions, such as that people are spying on them or are plotting to get them. Cocaine addicts often become distrustful of others because of these delusions. While cocaine addiction, unlike heroin addiction, does not always result in an inability to work and earn money, cocaine addicts do tend to turn to crime to buy their drugs. Theft, prostitution and drug dealing are frequently engaged in by cocaine addicts.
Amphetamines are stimulant drugs which were developed originally as
antihistamines. They were developed in Germany and were used by troops on both
sides in World War II to stay awake and alert. Like cocaine, amphetamines give
the user energy, pleasure and self-confidence. Because of this, in the 1950's,
amphetamines were tried as a treatment for depression. While amphetamines did
make the depressed person temporarily feel better, in the long run amphetamines
made their depression much worst. Amphetamines have been used by students to help
them study and learn, by athletes to improve performance, by musicians to motivate
themselves to perform repetitive concerts, by truck drivers to stay alert on a
long haul, and as diet pills to help people lose weight. However, their only
medical uses today are for the treatment of Attention Deficit Disorder (ADD) and
for the treatment of narcolepsy. However, another stimulant drug, Ritalin is
preferred to amphetamines for the treatment of ADD. Illicitly, they are still
used for all of the previously mentioned purposes.
Amphetamines speed up heart rate, respiration and increase blood pressure.
Because of these, and because they give the user energy, they are often called
speed.
Amphetamines create a surplus of many neurotransmitters, including dopamine. Like
cocaine addicts, amphetamine addicts often exhibit symptoms of paranoid
schizophrenia. They become suspicious that others are spying on them or plotting
to get them. Since they believe their delusions, they often strike first. For
this reason they can be dangerous. Amphetamines tend to make people more
aggressive.
While almost all drug abuse produces tolerance, amphetamines abuse results in a greater tolerance than most other drugs. Tolerance means that the more you use a drug, the more of the drug you must use to get the same feelings. This is why amphetamine addicts can start with 25 milligrams a day and work their way up to several thousand milligrams a day. Like cocaine, physical dependence is low and psychological dependence is high. Like cocaine, amphetamines can cause a permanent reduction in dopamine production in the brain, resulting in a permanent disability to experience normal pleasure. Like cocaine, amphetamines can also cause a stroke.
Technology has also made amphetamines very addictive. Used in a medical dosage, addiction usually does not occur. However, when technology is used to strengthen amphetamine into methamphetamine hydrochloride (crank) it becomes extremely addictive. Many experts believe that crank is even more addictive than crack.
Alcohol is a drug that has been consumed since at least the advent of agriculture. Crops which contain sugar can be converted to alcohol by the action of yeast or bacteria. Sugar cane, wheat, barley, rice and even potatoes can be used to make alcoholic beverages.
Technology also caused alcohol to become more addictive. The first alcoholic
beverages were wines, beers and ales. A sugar containing plant was placed in
water and yeast and bacteria fermented the sugar to alcohol. Because of the high
water content, these alcoholic beverages contained a rather low percentage of
alcohol. However, the technology known as distillation allowed people to produce
alcoholic beverages that had a higher alcohol content. A sugar containing plant
was placed in a kettle with water, mashed to provide the yeast and bacteria with
more surface area, and allowed to ferment. Then heat was applied to the mash.
Alcohol vaporizes at a lower temperature than does water. So if the mash is
heated to about 180 degrees Fahrenheit, much alcohol is vaporized with only a
little water vapor. A lid is placed on the kettle and a coiled up tube is
attached to the lid. As the vaporized alcohol goes through the coil it cools and
condenses back into a liquid. If done correctly, a beverage containing about 90%
alcohol can be distilled. The higher the alcohol content, the greater the
potential for addiction.
Alcohol is a depressant drug. This means that it lessens the effect of neurotransmitters in the nervous system. This causes one to slur their speech, lose the ability to react quickly, and lose the ability to coordinate movements of the body. This is why it is not a good idea to drink alcohol and drive. Movement (motor) coordination is impaired by alcohol, as is thinking and judgment. Research has shown that an blood-alcohol concentration of .08% is the level at which a person should not drive a car. This is the legal limit for blood-alcohol content for drivers in most states.
It is very possible for a person to drink themselves to death. Death occurs
because there is insufficient neurotransmitters for the nervous system to create
breathing.
Alcohol is a drug to which one develops tolerance. This means the more you drink, the more you are capable of drinking. While most people who drink alcohol do not become alcoholics, almost one in ten will develop alcoholism. Genetics has been shown to be an important factor in alcoholism. Alcoholism tend to run in families and alcoholism has ethnic preferences. Alcohol is metabolized (broken down) by the liver. If, because of genetics, one has a high amount of the metabolite for alcohol produced by their liver, they will get a more pleasurable response to alcohol than one with smaller amounts of the metabolite. People with very small amounts of the metabolite for alcohol get sick from alcohol very easily. Oriental people have low amounts of this metabolite. Because of this, alcoholism is rare in most oriental countries. However, some people of Irish descent and Native Americans tend to have large amounts of the metabolite, and high rates of alcoholism.
All alcohols are poisonous to people. However, drinking alcohol (ethanol or ethyl alcohol) is the least poisonous. Being a poison, all alcohol is damaging to the body. Alcohol is converted by the liver into acetic acid, an acid used to make vinegar. This acetic acid can "pickle," damage, and scar the liver. The medical term for scaring of the liver is cirrhosis of the liver. Alcohol can also damage the brain. Alcohol destroys the connections between nerve fibers in the brain. This causes alcoholics to have blackouts, long periods of time for which they remember nothing. However, recent studies in Sweden indicate that many of these connections are restored when one stops drinking alcohol. Alcohol abuse also causes heart disease and stroke.
When an alcoholic withdraws from alcohol, withdrawal can result in delirium tremens (DTS). DTs are characterized by sweating, nervousness, seizures, shakes, and hallucinations.
Alcoholism is a difficult disease to treat. One treatment for alcoholism is the drug Anabuse. Anabuse ties up the metabolite for alcohol and makes the alcoholic physically sick should they drink. Alcoholics Anonymous (AA) is also an effective therapy, although AA keeps no records of success and failure. AA is a religion-based support group for alcoholics in which alcoholics help other alcoholics. No alcoholic is ever considered cured. If the alcoholic stops drinking, it is said to be alcoholism in remission. Generally, one drink will send them immediately back into active alcoholism.
Marijuana is the term of the flowering tops and leaves of the plant cannabis sativa. Marijuana has characteristics of both stimulant and depressant drugs. Because of this, it is not classed as either, but as a hallucinogenic drug. Powerful marijuana products such as hashish and hashish oil will cause hallucinations.
Marijuana distorts the perception of time, so that time appears to pass very slowly. Marijuana interferes with the consolidation of memories, so that things may be forgotten very quickly. It stimulates hunger centers of the brain, causing a craving for food--especially sweet foods. It drys up salivary glands causing a dry mouth. And while the marijuana high can be very frightening to some people, it can be very relaxing for others.
The active drug in marijuana is tetrahydrocannabinol (THC). THC is found in its highest concentration in the female plant. THC is a very sticky substance. One of the functions of THC is to cause pollen to stick, so that reproduction can occur. If reproduction is prevented, the female plant produces more and more THC in an attempt to catch pollen. Another aspect of technology, selective breeding, has resulted in marijuana that contains very large amounts of THC. The marijuana of the 1960's, for example, contained 1-2% THC. Today's marijuana can be over 25% THC.
Marijuana has an effect on motivation. Motivation refers to what we want and need. In the marijuana induced amotivational syndrome, wants and needs change. If the person previously wanted to be successful in school, they may now find school to be unimportant to them. If the person previously wanted to be very successful in life, they may now lack the motivation for success. If the person previously wanted to do very beneficial things for mankind, they may lose this concern. Marijuana also has an effect on memory.
A structure of the brain called the hippocampus is known to be important for
consolidating experience into memories. The hippocampus is damaged by habitual
marijuana use. In some, the hippocampus is damaged in just a few months of
habitual use. In others it takes years before detectable damage occurs. But in
all habitual users of marijuana this damage will eventually occur.
Lysergic Acid diethylamide (LSD) is a hallucinogenic drug. It was developed accidentally by a chemist named Hoffman in the 1930's. Since LSD caused hallucinations, it was believed that something like LSD was in the brains of schizophrenics. It was hoped that LSD research would led to a cure for this mental illness. However, this did not occur. There are differences between schizophrenic hallucinations and the hallucinations produced by LSD. In schizophrenia, the hallucinations are primarily auditory--they hear things such as voices. With LSD the hallucinations are primarily visual.
LSD produces hallucinations by blocking the action of neurotransmitters in the
brain. An LSD trip can be fun, but it can also be very frightening.
Psychological dependence is low, and physical dependence does not develop. The
greatest danger from LSD is that faulty perceptions of reality can result in
injury or death. However, if a person is prone to the mental illness of
schizophrenia, LSD can trigger that mental illness, which will remain with them
for life. Another danger is that illegal LSD often contains impurities, such as
strychnine, which can cause paralysis and brain damage.