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One cell differs from another—a liver cell looks and acts differently from a brain cell, for example—because, in each, certain genes are turned on, while others are turned off. Cocaine produces dopamine buildup wherever the brain has dopamine transporters. Dopamine-responsive cells are highly concentrated in this system, which controls emotional responses and links them with memories. The more dopamine molecules come into contact with receptors, the more the electrical properties of the receiving cells are altered.

This had no impact on the peer review process and the final decision. Developing an FDA-approved e-cigarette for smoking cessation could improve public health. Cocaine is mostly available as an illegal drug that some people use to get high.

The receiving cells’ response makes us feel good and want to repeat the activity and reexperience that pleasure. As with other drugs, repeated use of cocaine can cause long-term changes in the brain’s reward circuit and other brain systems, which may lead to addiction. The reward circuit eventually adapts to the extra dopamine caused by the drug, becoming steadily less sensitive to it.

An initial, short-term effect—a buildup of the neurochemical dopamine—gives rise to euphoria and a desire to take the drug again. Researchers are seeking to understand how cocaine’s many longer term effects produce addiction’s persistent cravings and risk of relapse. In the author’s laboratory, work has focused on buildup of the genetic transcription factor ΔFosB. Levels of ΔFosB in the limbic system correlate with addiction-like behaviors in mice and may precipitate very long-lasting changes to nerve cell structure.

Expert assistance with toxicology interpretations can improve the accuracy of drug test results. While a medication that counters the powerful biological forces of addiction is essential, it will not be a “magic bullet.” People in recovery from addiction will always need support and rehabilitation to rebuild their lives. Presumably, effective psychosocial treatments for addiction work by causing changes in the brain, perhaps even some of the same changes that will be produced by effective medications. While very little information is currently available on the neurobiological mechanisms underlying psychosocial treatments, this is a topic of great interest. Finding addiction vulnerability genes will enable us to identify individuals who are at particular risk for an addictive disorder and target them for educational and other preventive measures.

However, chronic administration of cocaine has recently been shown to increase ΔFosB in several additional brain regions, such as the frontal cortex and amygdala (McClung et al., 2004). The accumulations of ΔFosB are much smaller in these regions than those that cocaine causes in the NAc, and their behavioral consequences are still unknown. It is tempting to speculate, though, that the presence of ΔFosB in the frontal cortex may contribute to the loss of frontal cortex control over cocaine urges that is seen in addiction. Although we do not yet have direct evidence of this possibility, it represents an additional mechanism by which ΔFosB may contribute to a state of addiction.

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Still other approaches attempt to take advantage of the fact that cocaine’s acute effects on the brain involve increased activation of dopamine receptors. NAc nerve cells make five types of dopamine receptors; drugs that affect the functioning of one or more of them could, in theory, produce a palliative effect on cocaine addiction. Efforts are under way in each of these areas, including clinical trials, but so far no clear breakthrough has been reported. Cocaine produces its psychoactive and addictive effects primarily by acting on the brain’s limbic system, a set of interconnected regions that regulate pleasure and motivation.

Long-term health effects of cocaine include:

NIDA is a biomedical research organization and does not provide personalized medical advice, treatment, counseling, or legal consultation. Information provided by NIDA is not a substitute for professional medical care or legal consultation. Drugs like cocaine powerfully activate reward and reinforcement mechanisms in the brain.

How does cocaine affect the brain?

Sometimes drug dealers mix it with flour or corn starch to increase profits. A recent report on extensive surveillance of cocaine use andrelated health consequences compiled by the National Institute on DrugAbuse (NIDA) of the U.S. Increasing how does cocaine produce its effects national institute on drug abuse nida the number of people achieving long-term recovery from SUDs is a national policy priority and a major goal of…

• Brain imaging studies of people with addiction show physical changes in areas of the brain that are critical to judgment, decision-making, learning and memory, and behavior control.12 These changes help explain the compulsive nature of addiction.
• Different brain circuits are responsible for coordinating and performing specific functions.
• In general, the more risk factors a person has, the greater the chance that taking drugs will lead to drug use and addiction.
• It is important to follow specific instructions and send a urine sample to a laboratory for confirmation.

What parts of the brain are affected by drug use?

This pattern of low cost was believed to reflect theroute of administration most commonly used, i.e., sniffing or”snorting,” and an estimated low prevalence of chronic use. However,use of cocaine has increased substantially in the United States sincethat time. A more recent report indicates that almost 10 millionpeople over the age of 11 years reported having used cocaine duringthe year preceding the survey, and almost half of these had usedcocaine during the month before the survey (2). Two-thirds of theseself-reported cocaine users were between the ages of 18 and 25 years.Overall, the number of people in the United States reporting cocaineuse in 1979 was more than double that in 1977 (3). Additional surveydata from 1975 through 1981 show a similar trend for graduating highschool seniors (4).

• Some drugs, such as marijuana and heroin, can activate neurons because their chemical structure mimics that of a natural neurotransmitter in the body.
• Cocaine increases levels of the natural chemical messenger dopamine in brain circuits related to the control of movement and reward.
• This includes clinical chemists or medical toxicologists at hospitals, clinics, or poison control centers.
• A drug test looks for the presence or absence of a drug in a biological sample, such as urine, blood, or hair.

Do people choose to keep using drugs?

Also, the person will often need to take larger amounts of the drug to produce the familiar high—an effect known as tolerance. Just as drugs produce intense euphoria, they also produce much larger surges of dopamine, powerfully reinforcing the connection between consumption of the drug, the resulting pleasure, and all the external cues linked to the experience. Large surges of dopamine “teach” the brain to seek drugs at the expense of other, healthier goals and activities. As with other diseases and disorders, the likelihood of developing an addiction differs from person to person, and no single factor determines whether a person will become addicted to drugs. In general, the more risk factors a person has, the greater the chance that taking drugs will lead to drug use and addiction. Risk and protective factors may be either environmental or biological.

Reduced drug use is a meaningful treatment outcome for people with stimulant use disorders

Cocaine is a stimulant that can make you feel like you have more energy and are extra alert. But it can also make you feel restless, grouchy, anxious, panicked, and paranoid. Pleasurable experience, a burst of dopamine signals that something important is happening that needs to be remembered. This dopamine signal causes changes in neural connectivity that make it easier to repeat the activity again and again without thinking about it, leading to the formation of habits. According to research, cocaine impairs immune cell function and promotes reproduction of the HIV virus.

Can cocaine affect your brain and body?

As a result, people take stronger and more frequent doses to feel the same high they did initially and to obtain relief from withdrawal. For the brain, the difference between normal rewards and drug rewards can be likened to the difference between someone whispering into your ear and someone shouting into a microphone. Just as we turn down the volume on a radio that is too loud, the brain of someone who misuses drugs adjusts by producing fewer neurotransmitters in the reward circuit, or by reducing the number of receptors that can receive signals. As a result, the person’s ability to experience pleasure from naturally rewarding (i.e., reinforcing) activities is also reduced.

Other symptoms of cocaine overdose include difficulty breathing, high blood pressure, high body temperature, hallucinations, and extreme agitation or anxiety. (Main panel) Cocaine causes the neurotransmitter dopamine to build up at the interface between VTA cells and NAc cells, triggering pleasurable feelings and NAc cellular activities that sensitize the brain to future exposures to the drug. Among the activities are increased production of genetic transcription factors, including ΔFosB; altered gene activity; altered production of potentially many proteins; and sprouting of new dendrites and dendritic spines. If a drug test result is positive during substance use disorder treatment, health care providers may prescribe additional or alternative treatments. However, actual consequences of a positive drug test during substance use treatment may depend on state laws and the individual program.

Each neuron acts as a switch controlling the flow of information. If a neuron receives enough signals from other neurons that it is connected to, it fires, sending its own signal on to other neurons in the circuit. This three-pound mass of gray and white matter sits at the center of all human activity—you need it to drive a car, to enjoy a meal, to breathe, to create an artistic masterpiece, and to enjoy everyday activities. The brain regulates your body’s basic functions, enables you to interpret and respond to everything you experience, and shapes your behavior.

• When stimulated by dopamine, cells in the NAc produce feelings of pleasure and satisfaction.
• Although cocaine also inhibits the transporters for other neurotransmitter chemicals (norepinephrine and serotonin), its actions on the dopamine system are generally thought to be most important.
• Cocaine is typically used orally, intranasally, intravenously, or by inhalation.
• Although health care providers can use it for valid medical purposes, such as local anesthesia for some surgeries, recreational cocaine use is illegal.
• As a result, people take stronger and more frequent doses to feel the same high they did initially and to obtain relief from withdrawal.

Can NIDA assist me with interpreting or disputing the results of a drug screen?

Injecting or smoking cocaine produces a quicker and stronger but shorter-lasting high than snorting. Effective medications for treating cocaine addiction will eventually be developed, and the best strategy for progress in this area is to target neurobio-logical mechanisms, such as those described above. Although the process takes a very long time—it can take 10 to 20 how does cocaine produce its effects national institute on drug abuse nida years to advance from identification of a disease mechanism to development of a new treatment—this work is in progress and represents the best hope for those who are addicted. (Graph inset) The time courses of cocaine-induced buildup of ΔFosB and cocaine-related structural changes (dendrite sprouting) suggest that these neurobiological effects may underlie some of the drug’s short-term, medium-term, and long-term behavioral effects. Every individual is born with a unique combination of roughly 30,000 genes.

There was a substantial increase in the number ofthese students who reported having used cocaine both during the yearand the month preceding the survey, i.e., from 5.6% to 12.4% and from1.9% to 5.8%, respectively. The brain is often likened to an incredibly complex and intricate computer. Instead of electrical circuits on the silicon chips that control our electronic devices, the brain consists of billions of cells, called neurons, which are organized into circuits and networks.

• Now, the person needs to keep taking drugs to experience even a normal level of reward—which only makes the problem worse, like a vicious cycle.
• Cocaine affects the expression of numerous genes within the NAc, including some that influence the important neurotransmitter chemical glutamate and the brain’s natural opioid-like compounds produced by the body (Kalivas and McFarland, 2003; Nestler, 2001).
• If left untreated, they can last a lifetime and may lead to death.
• This finding has shed new light on mechanisms underlying cocaine’s very long-lasting effects on the brain (Nestler, 2001).
• Risk and protective factors may be either environmental or biological.

Although cocaine also inhibits the transporters for other neurotransmitter chemicals (norepinephrine and serotonin), its actions on the dopamine system are generally thought to be most important. To understand the powerful nature of cocaine’s actions, it is helpful to realize that dopamine pathways in the brain are very old in evolutionary terms. Early rudiments are found in worms and flies, which take us back 2 billion years in evolution. Thus, cocaine alters a neural circuit in the brain that is of fundamental importance to survival. Such alterations affect the individual in profound ways that scientists are still trying to understand.

While NIDA-supported research may inform the development and validation of drug-screening technologies, NIDA does not manufacture, regulate, or distribute laboratory or at-home drug screening products. The U.S. Food and Drug Administration (FDA) regulates most of these products in the United States. Those with concerns about drug screening results may consider reaching out to the drug-screening program or a qualified health care professional.

For more information on workplace drug screening, please visit the Substance Abuse and Mental Health Services Administration (SAMSHA) Division of Workplace Programs website. The specific genes that confer risk for cocaine addiction remain unknown. One possibility is that at least some of them are the same genes that are affected by cocaine exposure. For example, variations in the genes encoding ΔFosB or any of hundreds of other genes affected by cocaine could conceivably contribute to the genetic risk for addiction. It is also possible that other genes—genes not affected by cocaine exposure—are responsible. However, instead of leaving the cell that produces it and stimulating neighboring cells as dopamine does, ΔFosB remains in its original cell and stimulates certain genes.

The Neurobiology of Cocaine Addiction

Drug testing can sometimes also detect passive exposure to drugs, such as secondhand smoke or prenatal exposure. The length of time following exposure that a drug can be detected during testing can vary. Drug testing is different than “drug checking,” which helps people who use drugs determine which chemicals are found in the substance they intend to take. Snorted, smoked, or injected, cocaine rapidly enters the bloodstream and penetrates the brain. The drug achieves its main immediate psychological effect—the high—by causing a buildup of the neurochemical dopamine.

FROM THE RUSH TO THE ADDICTION, COCAINE’S EFFECTS IN THE BRAIN.

This too amplifies or disrupts the normal communication between neurons. One of the brain areas still maturing during adolescence is the prefrontal cortex—the part of the brain that allows people to assess situations, make sound decisions, and keep emotions and desires under control. The fact that this critical part of a teen’s brain is still a work in progress puts them at increased risk for trying drugs or continuing to take them. Introducing drugs during this period of development may cause brain changes that have profound and long-lasting consequences. When they first use a drug, people may perceive what seem to be positive effects.

Drug Misuse and Addiction

To keep the receiving cells in each brain region functioning at appropriate intensities for current demands—neither too high nor too low—the dopaminergic cells continually increase and decrease the number of dopamine molecules they launch. They further regulate the amount of dopamine available to stimulate the receptors by pulling some previously released dopamine molecules back into themselves. An initial report from the early 1970s stated that little cost tosociety attributed to cocaine use had been verified in the UnitedStates (1).

To date, most efforts to develop new medications for treatment of cocaine addiction have focused on preventing or suppressing the drug’s acute effects. Cocaine “vaccines,” for example, are designed to bind cocaine molecules in the blood with antibodies and so keep them from getting into the brain. A related approach seeks to develop a medication that keeps cocaine from tying up the dopamine transporter without itself interfering with the transporter’s normal function of dopamine retrieval.

Among the most intriguing of these mechanisms is elevation of the genetic transcription factor ΔFosB, a molecule that lasts for approximately 2 months and theoretically can promote neuron structural changes that have potentially lifelong persistence. The most important goal for the next decade is to translate the knowledge we have already gained, along with any future advances we make, into better treatments for addiction. Scientists currently are working to identify which specific genes ΔFosB stimulates to produce its effects. Comparisons of genes expressed in NAc nerve cells in mice that make ΔFosB versus mice that lack the transcription factor have revealed more than a hundred ΔFosB-mediated changes in gene expression (McClung and Nestler, 2003).

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One particular part of the limbic system, the nucleus accumbens (NAc), seems to be the most important site of the cocaine high. When stimulated by dopamine, cells in the NAc produce feelings of pleasure and satisfaction. The natural function of this response is to help keep us focused on activities that promote the basic biological goals of survival and reproduction. When a thirsty person drinks or someone has an orgasm, for example, dopaminergic cells flood the NAc with dopamine molecules.

Cocaine increases levels of the natural chemical messenger dopamine in brain circuits related to the control of movement and reward. Normally, dopamine recycles back into the cell that released it, shutting off the signal between nerve cells. However, cocaine prevents dopamine from being recycled, causing large amounts to build up in the space between two nerve cells, stopping their normal communication. This flood of dopamine in the brain’s reward circuit strongly reinforces drug-taking behaviors. With continued drug use, the reward circuit may adapt, becoming less sensitive to the drug. As a result, people take stronger and more frequent doses in an attempt to feel the same high, and to obtain relief from withdrawal.

Why do some people become addicted to drugs, while others do not?

To send a message, a neuron releases a neurotransmitter into the gap (or synapse) between it and the next cell. The neurotransmitter crosses the synapse and attaches to receptors on the receiving neuron, like a key into a lock. Other molecules called transporters recycle neurotransmitters (that is, bring them back into the neuron that released them), thereby limiting or shutting off the signal between neurons.