How do opioids affect the brain and body?

Opioids act by attaching to specific proteins called opioid receptors, which are found in the brain, spinal cord, and gastrointestinal tract. When these drugs attach to certain opioid receptors, they can block the transmission of pain messages to the brain. In addition, opioids can produce drowsiness, cause constipation, and, depending upon the amount of drug taken, depress respiration. Opioid drugs also can cause euphoria by affecting the brain regions that mediate what we perceive as pleasure.

What are the possible consequences of opioid use and abuse?

Chronic use of opioids can result in tolerance for the drugs, which means that users must take higher doses to achieve the same initial effects. Long-term use also can lead to physical dependence and addiction - the body adapts to the presence of the drug, and withdrawal symptoms occur if use is reduced or stopped. Symptoms of withdrawal include restlessness, muscle and bone pain, insomnia, diarrhea, vomiting, cold flashes with goose bumps ("cold turkey"), and involuntary leg movements. Finally, taking a large single dose of an opioid could cause severe respiratory depression that can lead to death. Many studies have shown, however, that properly managed medical use of opioid analgesic drugs is safe and rarely causes clinical addiction, defined as compulsive, often uncontrollable use of drugs. Taken exactly as prescribed, opioids can be used to manage pain effectively.

Is it safe to use opioid drugs with other medications?

Opioids are safe to use with other drugs only under a physician's supervision. Typically, they should not be used with other substances that depress the central nervous system, such as alcohol, antihistamines, barbiturates, benzodiazepines, or general anesthetics, as such a combination increases the risk of life-threatening respiratory depression.

What are CNS depressants?

CNS depressants are substances that can slow normal brain function. Because of this property, some CNS depressants are useful in the treatment of anxiety and sleep disorders. Among the medications that are commonly prescribed for these purposes are the following:

• Barbiturates, such as mephobarbital (Mebaral) and pentobarbital sodium (Nembutal), which are used to treat anxiety, tension, and sleep disorders.

• Benzodiazepines, such as diazepam (Valium), chlordiazepoxide HCl (Librium), and alprazolam (Xanax), which can be prescribed to treat anxiety, acute stress reactions, and panic attacks; the more sedating benzodiazepines, such as triazolam (Halcion) and estazolam (ProSom) can be prescribed for short-term treatment of sleep disorders.

• In higher doses, some CNS depressants can be used as general anesthetics.

How do CNS depressants affect the brain and body?

There are numerous CNS depressants; most act on the brain by affecting the neurotransmitter gamma-aminobutyric acid (GABA). Neurotransmitters are brain chemicals that facilitate communication between brain cells. GABA works by decreasing brain activity. Although the different classes of CNS depressants work in unique ways, ultimately it is through their ability to increase GABA activity that they produce a drowsy or calming effect that is beneficial to those suffering from anxiety or sleep disorders.

What are the possible consequences of CNS depressant use and abuse?

Despite their many beneficial effects, barbiturates and benzodiazepines have the potential for abuse and should be used only as prescribed. During the first few days of taking a prescribed CNS depressant, a person usually feels sleepy and uncoordinated, but as the body becomes accustomed to the effects of the drug, these feelings begin to disappear. If one uses these drugs long term, the body will develop tolerance for the drugs, and larger doses will be needed to achieve the same initial effects. In addition, continued use can lead to physical dependence and - when use is reduced or stopped - withdrawal. Because all CNS depressants work by slowing the brain's activity, when an individual stops taking them, the brain's activity can rebound and race out of control, possibly leading to seizures and other harmful consequences. Although withdrawal from benzodiazepines can be problematic, it is rarely life threatening, whereas withdrawal from prolonged use of other CNS depressants can have life-threatening complications. Therefore, someone who is thinking about discontinuing CNS depressant therapy or who is suffering withdrawal from a CNS depressant should speak with a physician or seek medical treatment.

Is it safe to use CNS depressants with other medications?

CNS depressants should be used with other medications only under a physician's supervision. Typically, they should not be combined with any other medication or substance that causes CNS depression, including prescription pain medicines, some over-the-counter cold and allergy medications, or alcohol. Using CNS depressants with these other substances - particularly alcohol - can slow breathing, or slow both the heart and respiration, and possibly lead to death.

What are stimulants?

As the name suggests, stimulants are a class of drugs that enhance brain activity - they cause an increase in alertness, attention, and energy that is accompanied by elevated blood pressure and increased heart rate and respiration. Stimulants were used historically to treat asthma and other respiratory problems, obesity, neurological disorders, and a variety of other ailments. But as their potential for abuse and addiction became apparent, the medical use of stimulants began to wane. Now, stimulants are prescribed for the treatment of only a few health conditions, including narcolepsy, attention-deficit hyperactivity disorder, and depression that has not responded to other treatments. Stimulants may be used as appetite suppressants for short-term treatment of obesity, and they also may be used for patients with asthma.

How do stimulants affect the brain and body?

Stimulants, such as dextroamphetamine (Dexedrine) and methylphenidate (Ritalin), have chemical structures that are similar to a family of key brain neurotransmitters called monoamines, which include norepinephrine and dopamine. Stimulants increase the amount of these chemicals in the brain. This, in turn, increases blood pressure and heart rate, constricts blood vessels, increases blood glucose, and opens up the pathways of the respiratory system. In addition, the increase in dopamine is associated with a sense of euphoria that can accompany the use of these drugs.

What are the possible consequences of stimulant use and abuse?

The consequences of stimulant abuse can be dangerous. Although their use may not lead to physical dependence and risk of withdrawal, stimulants can be addictive in that individuals begin to use them compulsively. Taking high doses of some stimulants repeatedly over a short time can lead to feelings of hostility or paranoia. Additionally, taking high doses of a stimulant may result in dangerously high body temperatures and an irregular heartbeat. There is also the potential for cardiovascular failure or lethal seizures.

Is it safe to use stimulants with other medications?

Stimulants should be used with other medications only when the patient is under a physician's supervision. For example, a stimulant may be prescribed to a patient taking an antidepressant. However, health care providers and patients should be mindful that antidepressants enhance the effects of a stimulant. Patients also should be aware that stimulants should not be mixed with over-the-counter cold medicines that contain decongestants, as this combination may cause blood pressure to become dangerously high or lead to irregular heart rhythms.

Trends in prescription drug abuse

Several indicators suggest that prescription drug abuse is on the rise in the United States. According to the 1999 National Household Survey on Drug Abuse, in 1998, an estimated 1.6 million Americans used prescription pain relievers nonmedically for the first time. This represents a significant increase since the 1980s, when there were generally fewer than 500,000 first-time users per year. From 1990 to 1998, the number of new users of pain relievers increased by 181 percent; the number of individuals who initiated tranquilizer use increased by 132 percent; the number of new sedative users increased by 90 percent; and the number of people initiating stimulant use increased by 165 percent. In 1999, an estimated 4 million people - almost 2 percent of the population aged 12 and older - were currently (use in past month) using certain prescription drugs nonmedically: pain relievers (2.6 million users), sedatives and tranquilizers (1.3 million users), and stimulants (0.9 million users).

Although prescription drug abuse affects many Americans, some trends of concern can be seen among older adults, adolescents, and women. In addition, health care professionals - including physicians, nurses, pharmacists, dentists, anesthesiologists, and veterinarians - may be at increased risk of prescription drug abuse because of ease of access, as well as their ability to self-prescribe drugs. In spite of this increased risk, recent surveys and research in the early 1990s indicate that health care providers probably suffer from substance abuse, including alcohol and drugs, at a rate similar to rates in society as a whole, in the range of 8 to 12 percent.

Older adults

The misuse of prescription drugs may be the most common form of drug abuse among the elderly. Elderly persons use prescription medications approximately three times as frequently as the general population and have been found to have the poorest rates of compliance with directions for taking a medication. In addition, data from the Veterans Affairs Hospital System suggest that elderly patients may be prescribed inappropriately high doses of medications such as benzodiazepines and may be prescribed these medications for longer periods than are younger adults. In general, older people should be prescribed lower doses of medications, because the body's ability to metabolize many medications decreases with age.

An association between age-related morbidity and abuse of prescription medications likely exists. For example, elderly persons who take benzodiazepines are at increased risk for falls that cause hip and thigh fractures, as well as for vehicle accidents. Cognitive impairment also is associated with benzodiazepine use, although memory impairment may be reversible when the drug is discontinued. Finally, use of benzodiazepines for longer than 4 months is not recommended for elderly patients because of the possibility of physical dependence.

Gender differences

Studies suggest that women are more likely than men to be prescribed an abusable prescription drug, particularly narcotics and anti-anxiety drugs - in some cases 48 percent more likely.

Overall, men and women have roughly similar rates of nonmedical use of prescription drugs. An exception is found among 12- to 17-year-olds: In this age group, young women are more likely than young men to use psychotherapeutic drugs nonmedically.

In addition, research has shown that women and men who use prescription opioids are equally likely to become addicted. However, among women and men who use either a sedative, anti-anxiety drug, or hypnotic, women are almost two times more likely to become addicted.

Preventing and detecting prescription drug abuse

Although most patients use medications as directed, abuse of and addiction to prescription drugs are public health problems for many Americans. However, addiction rarely occurs among those who use pain relievers, CNS depressants, or stimulants as prescribed; the risk for addiction exists when these medications are used in ways other than as prescribed. Health care providers such as primary care physicians, nurse practitioners, and pharmacists as well as patients can all play a role in preventing and detecting prescription drug abuse.

Treating prescription drug addiction

Years of research have shown us that addiction to any drug, illicit or prescribed, is a brain disease that can, like other chronic diseases, be effectively treated. But no single type of treatment is appropriate for all individuals addicted to prescription drugs. Treatment must take into account the type of drug used and the needs of the individual. To be successful, treatment may need to incorporate several components, such as counseling in conjunction with a prescribed medication, and multiple courses of treatment may be needed for the patient to make a full recovery.

The two main categories of drug addiction treatment are behavioral and pharmacological. Behavioral treatments teach people how to function without drugs, how to handle cravings, how to avoid drugs and situations that could lead to drug use, how to prevent relapse, and how to handle relapse should it occur. When delivered effectively, behavioral treatments - such as individual counseling, group or family counseling, contingency management, and cognitive-behavioral therapies - also can help patients improve their personal relationships and ability to function at work and in the community.

Some addictions, such as opioid addiction, can also be treated with medications. These pharmacological treatments counter the effects of the drug on the brain and behavior. Medications also can be used to relieve the symptoms of withdrawal, to treat an overdose, or to help overcome drug cravings. Although a behavioral or pharmacological approach alone may be effective for treating drug addiction, research shows that a combination of both, when available, is most effective.

Treating addiction to prescription opioids

Several options are available for effectively treating addiction to prescription opioids. These options are drawn from experience and research regarding the treatment of heroin addiction. They include medications, such as methadone and LAAM (levo-alpha-acetyl-methadol), and behavioral counseling approaches.

A useful precursor to long-term treatment of opioid addiction is detoxification. Detoxification in itself is not a treatment for opioid addiction. Rather, its primary objective is to relieve withdrawal symptoms while the patient adjusts to being drug free. To be effective, detoxification must precede long-term treatment that either requires complete abstinence or incorporates a medication, such as methadone, into the treatment plan.

Methadone is a synthetic opioid that blocks the effects of heroin and other opioids, eliminates withdrawal symptoms, and relieves drug craving. It has been used successfully for more than 30 years to treat people addicted to opioids. Other medications include LAAM, an alternative to methadone that blocks the effects of opioids for up to 72 hours, and naltrexone, an opioid blocker that is often employed for highly motivated individuals in treatment programs promoting complete abstinence. Buprenorphine, another effective medication, is awaiting Food and Drug Administration (FDA) approval for treatment of opioid addiction. Finally, naloxone, which counteracts the effects of opioids, is used to treat overdoses.

Treating addiction to CNS depressants

Patients addicted to barbiturates and benzodiazepines should not attempt to stop taking them on their own, as withdrawal from these drugs can be problematic, and in the case of certain CNS depressants, potentially life-threatening. Although no extensive body of research regarding the treatment of barbiturate and benzodiazepine addiction exists, patients addicted to these medications should undergo medically supervised detoxification because the dose must be gradually tapered off. Inpatient or outpatient counseling can help the individual during this process. Cognitive-behavioral therapy also has been used successfully to help individuals adapt to the removal from benzodiazepines.

Often the abuse of barbiturates and benzodiazepines occurs in conjunction with the abuse of another substance or drug, such as alcohol or cocaine. In these cases of polydrug abuse, the treatment approach must address the multiple addictions.

Treating addiction to prescription stimulants

Treatment of addiction to prescription stimulants, such as Ritalin, is often based on behavioral therapies proven effective for treating cocaine or methamphetamine addiction. At this time, there are no proven medications for the treatment of stimulant addiction. However, antidepressants may help manage the symptoms of depression that can accompany the early days of abstinence from stimulants.

Depending on the patient's situation, the first steps in treating prescription stimulant addiction may be tapering off the drug's dose and attempting to treat withdrawal symptoms. The detoxification process could then be followed by one of many behavioral therapies. Contingency management, for example, uses a system that enables patients to earn vouchers for drug-free urine tests. The vouchers can be exchanged for items that promote healthy living.

Another behavioral approach is cognitive-behavioral intervention, which focuses on modifying the patient's thinking, expectations, and behaviors while at the same time increasing skills for coping with various life stressors. Recovery support groups may also be effective in conjunction with behavioral therapy.