For teachers: Background information and classroom activities for use with the Opiates Student Booklet.
Opiates are powerful drugs derived from the poppy plant that have been used for centuries to relieve pain. They include opium, heroin, morphine, and codeine. Even centuries after their discovery, opiates are still the most effective pain relievers available to physicians for treating pain. Although heroin has no medicinal use, other opiates, such as morphine and codeine, are used in the treatment of pain related to illnesses (for example, cancer) and medical and dental procedures. When used as directed by a physician, opiates are safe and generally do not produce addiction. But opiates also possess very strong reinforcing properties and can quickly trigger addiction when used improperly.
Mechanism of Action
Opiates elicit their powerful effects by activating opiate receptors that are widely distributed throughout the brain and body. Once an opiate reaches the brain, it quickly activates the opiate receptors that are found in many brain regions and produces an effect that correlates with the area of the brain involved. Two important effects produced by opiates, such as morphine, are pleasure (or reward) and pain relief. The brain itself also produces substances known as endorphins that activate the opiate receptors. Research indicates that endorphins are involved in many things, including respiration, nausea, vomiting, pain modulation, and hormonal regulation.
When opiates are prescribed by a physician for the treatment of pain and are taken in the prescribed dosage, they are safe and there is little chance of addiction. However, when opiates are abused and/or taken in excessive doses, addiction can result. Findings from animal research indicate that, like cocaine and other abused drugs, opiates can also activate the brain's reward system. When a person injects, sniffs, or orally ingests heroin (or morphine), the drug travels quickly to the brain through the bloodstream. Once in the brain, the heroin is rapidly converted to morphine, which then activates opiate receptors located throughout the brain, including within the reward system. (Note: Because of its chemical structure, heroin penetrates the brain more quickly than other opiates, which is probably why many addicts prefer heroin.) Within the reward system, the morphine activates opiate receptors in the VTA, nucleus accumbens, and cerebral cortex (refer to the Introduction for information on the reward system). Research suggests that stimulation of opiate receptors by morphine results in feelings of reward and activates the pleasure circuit by causing greater amounts of dopamine to be released within the nucleus accumbens. This causes an intense euphoria, or rush, that lasts only briefly and is followed by a few hours of a relaxed, contented state. This excessive release of dopamine and stimulation of the reward system can lead to addiction.
Opiates also act directly on the respiratory center in the brainstem, where they cause a slowdown in activity. This results in a decrease in breathing rate. Excessive amounts of an opiate, like heroin, can cause the respiratory centers to shut down breathing altogether. When someone overdoses on heroin, it is the action of heroin in the brainstem respiratory centers that can cause the person to stop breathing and die.
As mentioned earlier, the brain itself produces endorphins that have an important role in the relief or modulation of pain. Sometimes, though, particularly when pain is severe, the brain does not produce enough endorphins to provide pain relief. Fortunately, opiates, such as morphine are very powerful pain relieving medications. When used properly under the care of a physician, opiates can relieve severe pain without causing addiction.
Feelings of pain are produced when specialized nerves are activated by trauma to some part of the body, either through injury or illness. These specialized nerves, which are located throughout the body, carry the pain message to the spinal cord. After reaching the spinal cord, the message is relayed to other neurons, some of which carry it to the brain. Opiates help to relieve pain by acting in both the spinal cord and brain. At the level of the spinal cord, opiates interfere with the transmission of the pain messages between neurons and therefore prevent them from reaching the brain. This blockade of pain messages protects a person from experiencing too much pain. This is known as analgesia.
Opiates also act in the brain to help relieve pain, but the way in which they accomplish this is different than in the spinal cord.
There are several areas in the brain that are involved in interpreting pain messages and in subjective responses to pain. These brain regions are what allow a person to know he or she is experiencing pain and that it is unpleasant. Opiates also act in these brain regions, but they don't block the pain messages themselves. Rather, they change the subjective experience of the pain. This is why a person receiving morphine for pain may say that they still feel the pain but that it doesn't bother them anymore.
Although endorphins are not always adequate to relieve pain, they are very important for survival. If an animal or person is injured and needs to escape a harmful situation, it would be difficult to do so while experiencing severe pain. However, endorphins that are released immediately following an injury can provide enough pain relief to allow escape from a harmful situation. Later, when it is safe, the endorphin levels decrease and intense pain may be felt. This also is important for survival. If the endorphins continued to blunt the pain, it would be easy to ignore an injury and then not seek medical care.
There are several types of opiate receptors, including the delta, mu, and kappa receptors. Each of these three receptors is involved in controlling different brain functions. For example, opiates and endorphins are able to block pain signals by binding to the mu receptor site.
The powerful technology of cloning has enabled scientists to copy the genes that make each of these receptors. This in turn is allowing researchers to conduct laboratory studies to better understand how opiates act in the brain and, more specifically, how opiates interact with each opiate receptor to produce their effects. This information may eventually lead to more effective treatments for pain and opiate addiction.
The following activities, when used along with the magazine on opiates, will help explain to students how these substances change the brain and the body.
All materials appearing in the Research Report Series are in the public domain and may be reproduced without permission from NIDA. Citation of the source is appreciated.
The student will learn the way in which opiates alter the function of nerve cells.
Remind students that long-term abuse of opiates, such as heroin, changes the way nerve cells in the brain work. These cells become so used to having the heroin present that they need it to work normally. This, in turn, leads to addiction. If opiates are taken away from dependent nerve cells, these cells become overactive. Eventually, they will work normally again, but in the meantime, they create a range of symptoms known as withdrawal. Have students create visual representations of normal nerve cells, dependent nerve cells, overactive nerve cells, and an opiate. Then have the students use these representations to develop, in comic art format, the process by which opiates change the normal functioning of neurons.
All materials appearing in the Research Reports series are in the public domain and may be reproduced without permission from NIDA. Citation of the source is appreciated.
The student will learn how opiates produce an analgesic effect.
Note that opiates are powerful painkillers and are used medically for treatment of pain. When used properly for medical purposes, opiates do not produce an intense feeling of pleasure, and patients have little chance of becoming addicted. Have students search the Internet and other sources for information about pain, pain control, and the way opiates produce their analgesic effect and then prepare a brief summary report.
Some over-the-counter (OTC) and prescription cough and cold medicines contain active ingredients that are psychoactive (mind-altering) at higher-than-recommended dosages and are frequently abused for this purpose. These products may also contain other drugs, such as expectorants and antihistamines, which are dangerous at high doses and compound the dangers of abuse.
Two commonly abused cough and cold medicines are:
- Dextromethorphan (DXM), a cough suppressant and expectorant found in many OTC cold medicines. It may produce euphoria and dissociative effects or even hallucinations when taken in quantities greater than the recommended therapeutic dose.
- Promethazine-codeine cough syrup, a medication that contains codeine, an opioid that acts as a cough suppressant and can also produce relaxation and euphoria when consumed at a higher-than-prescribed dose. It also contains promethazine HCl, an antihistamine that additionally acts as a sedative. Although only available by prescription, promethazine-codeine cough syrup is sometimes diverted for abuse.
How Are Cough and Cold Medicines Abused?
Cough and cold medicines are usually consumed orally in tablet, capsule, or syrup form. They may be mixed with soda for flavor and are often abused in combination with other drugs, such as alcohol or marijuana.
Because they are easily purchased in drugstores without a prescription, cough syrups, pills, and gel capsules containing DXM—particularly “extra strength” forms—are frequently abused by young people (who refer to the practice as “robo-tripping” or “skittling”). To avoid nausea produced by high doses of the expectorant guaifenesin commonly found in DXM-containing syrups, young people may instead abuse Coricidin® HBP Cough & Cold capsules (street name C-C-C or triple-C), which contain DXM but lack guaifenesin.
Drinking promethazine-codeine cough syrup mixed with soda (a combination called syrup, sizzurp, purple drank, barre, or lean) was referenced frequently in some popular music beginning in the late 1990s and has become increasingly popular among youth in several areas of the country. A variation of “purple drank” is promethazine-codeine cough syrup mixed with alcohol. Users may also flavor the mixture with the addition of hard candies.
How Does Abusing Cough and Cold Medicines Affect the Brain?
When taken as intended, cough and cold medicines safely treat symptoms of lower and upper respiratory congestion and discomfort caused by colds and flu. But when taken in higher quantities or when such symptoms aren’t present, they may affect the brain in ways very similar to illegal drugs.
When taken in high doses, DXM acts on the same cell receptors as dissociative hallucinogenic drugs like PCP or ketamine. Users describe effects ranging from mild stimulation to alcohol- or marijuana-like intoxication, and at high doses, sensations of physical distortion and hallucinations.
Codeine attaches to the same cell receptors targeted by illegal opioids like heroin. Consuming more than the daily recommended therapeutic dose of promethazine-codeine cough syrup can produce euphoria similar to that produced by other opioid drugs; people addicted to codeine may consume several times the recommended, safe amount. Also, both codeine and promethazine HCl act as depressants of the central nervous system, producing sedating or calming effects.
When abused, both codeine and DXM directly or indirectly cause a pleasurable increase in the amount of dopamine in the brain’s reward pathway. Repeatedly seeking to experience that feeling can lead to addiction—a chronic relapsing brain disease characterized by inability to stop using a drug despite damaging consequences to a person’s life and health.
What Are the Other Health Effects of Abusing Cough and Cold Medicines?
Abusing DXM can cause impaired motor function, numbness, nausea or vomiting, increased heart rate and blood pressure, and at high doses, extreme agitation, increased body temperature, and a buildup of excess acid in body fluids. High doses of acetaminophen, a pain reliever commonly found with DXM, can cause liver damage. On rare occasions, hypoxic brain damage—caused by severe respiratory depression and a lack of oxygen to the brain—has occurred as a result of the combination of DXM with decongestants often found in the medication.
When abused, promethazine-codeine cough syrup presents a high risk of fatal overdose due to its effect of depressing the central nervous system, which can slow or stop the heart and lungs. Mixing with alcohol greatly increases this risk. Promethazine-codeine cough syrup has been linked to the overdose deaths of a few prominent musicians.
For more information on abuse of DXM, see
http://www.deadiversion.usdoj.gov/drug_chem_info/dextro_m.pdf (PDF, 37KB)
For more information on abuse of promethazine-codeine cough syrup, see
Tal vez hayas oído de ciertas drogas como la heroína, la morfina o la codeína. Éstas son ejemplos de opiáceos. Si alguien usa opiáceos una y otra vez, es probable que su cerebro comience a depender de estas drogas.
Some medications have psychoactive (mind-altering) properties and, because of that, are sometimes abused—that is, taken for reasons or in ways or amounts not intended by a doctor, or taken by someone other than the person for whom they are prescribed. In fact, prescription and over-the-counter (OTC) drugs are, after marijuana (and alcohol), the most commonly abused substances by Americans 14 and older.
The classes of prescription drugs most commonly abused are: opioid pain relievers, such as Vicodin or Oxycontin; stimulants for treating Attention Deficit Hyperactivity Disorder (ADHD), such as Adderall, Concerta, or Ritalin; and central nervous system (CNS) depressants for relieving anxiety, such as Valium or Xanax.1 The most commonly abused OTC drugs are cough and cold remedies containing dextromethorphan.
People often think that prescription and OTC drugs are safer than illicit drugs, but that’s only true when they are taken exactly as prescribed and for the purpose intended. When abused, prescription and OTC drugs can be addictive and put abusers at risk for other adverse health effects, including overdose—especially when taken along with other drugs or alcohol.
How Are Prescription Drugs Abused?
Prescription and OTC drugs may be abused in one or more of the following ways:
Taking a medication that has been prescribed for somebody else. Unaware of the dangers of sharing medications, people often unknowingly contribute to this form of abuse by sharing their unused pain relievers with their family members.Most teenagers who abuse prescription drugs are given them for free by a friend or relative.
Taking a drug in a higher quantity or in another manner than prescribed. Most prescription drugs are dispensed orally in tablets, but abusers sometimes crush the tablets and snort or inject the powder. This hastens the entry of the drug into the bloodstream and the brain and amplifies its effects.
Taking a drug for another purpose than prescribed. All of the drug types mentioned can produce pleasurable effects at sufficient quantities, so taking them for the purpose of getting high is one of the main reasons people abuse them.
ADHD drugs like Adderall are also often abused by students seeking to improve their academic performance. However, although they may boost alertness, there is little evidence they improve cognitive functioning for those without a medical condition.
How Do Prescription and OTC Drugs Affect the Brain?
Taken as intended, prescription and OTC drugs safely treat specific mental or physical symptoms. But when taken in different quantities or when such symptoms aren’t present, they may affect the brain in ways very similar to illicit drugs.
For example, stimulants such as Ritalin achieve their effects by acting on the same neurotransmitter systems as cocaine. Opioid pain relievers such as OxyContin attach to the same cell receptors targeted by illegal opioids like heroin. Prescription depressants produce sedating or calming effects in the same manner as the club drugs GHB and rohypnol. And when taken in very high doses, dextromethorphan acts on the same cell receptors as PCP or ketamine, producing similar out-of-body experiences.
When abused, all of these classes of drugs directly or indirectly cause a pleasurable increase in the amount of dopamine in the brain’s reward pathway. Repeatedly seeking to experience that feeling can lead to addiction.
What Are the Other Health Effects of Prescription and OTC Drugs?
Opioids can produce drowsiness, cause constipation, and—depending upon the amount taken—depress breathing. The latter effect makes opioids particularly dangerous, especially when they are snorted or injected or combined with other drugs or alcohol.
Opioids and Brain Damage
While the relationship between opioid overdose and depressed respiration (slowed breathing) has been confirmed, researchers are also studying the long-term effects on brain function. Depressed respiration can affect the amount of oxygen that reaches the brain, a condition called hypoxia. Hypoxia can have short- and long-term psychological and neurological effects, including coma and permanent brain damage.
Researchers are also investigating the long-term effects of opioid addiction on the brain. Studies have shown some deterioration of the brain’s white matter due to heroin use, which may affect decision-making abilities, the ability to regulate behavior, and responses to stressful situations.
More people die from overdoses of prescription opioids than from all other drugs combined, including heroin and cocaine (see "The Prescription Opioid Abuse Epidemic" below).
The Prescription Opioid Abuse Epidemic
Over 2 million people in the United States suffer from substance use disorders related to prescription opioid pain relievers. The terrible consequences of this epidemic include overdose deaths, which have more than quadrupled in the past decade and a half. The causes are complex, but they include overprescription of pain medications. In 2013, 207 million prescriptions were written for prescription opioid pain medications.
Stimulants can have strong effects on the cardiovascular system. Taking high doses of a stimulant can dangerously raise body temperature and cause irregular heartbeat or even heart failure or seizures. Also, taking some stimulants in high doses or repeatedly can lead to hostility or feelings of paranoia.
CNS depressants slow down brain activity and can cause sleepiness and loss of coordination. Continued use can lead to physical dependence and withdrawal symptoms if discontinuing use.
Prescription Opioid Abuse: A First Step to Heroin Use?
Prescription opioid pain medications such as Oxycontin and Vicodin can have effects similar to heroin when taken in doses or in ways other than prescribed, and research now suggests that abuse of these drugs may actually open the door to heroin abuse.
Nearly half of young people who inject heroin surveyed in three recent studies reported abusing prescription opioids before starting to use heroin. Some individuals reported taking up heroin because it is cheaper and easier to obtain than prescription opioids.
Many of these young people also report that crushing prescription opioid pills to snort or inject the powder provided their initiation into these methods of drug administration.
Dextromethorphan can cause impaired motor function, numbness, nausea or vomiting, and increased heart rate and blood pressure. On rare occasions, hypoxic brain damage—caused by severe respiratory depression and a lack of oxygen to the brain—has occurred due to the combination of dextromethorphan with decongestants often found in the medication.
All of these drugs have the potential for addiction, and this risk is amplified when they are abused. Also, as with other drugs, abuse of prescription and OTC drugs can alter a person’s judgment and decision making, leading to dangerous behaviors such as unsafe sex and drugged driving.
For more information on prescription and OTC drugs, please refer to the following sources on NIDA’s Web site:
- Research Report: Prescription Drugs
- Prescription Stimulants (Abuse) Health Effects
- Prescription Sedatives, sleeping pills*, or anxiolytics (Abuse) Health Effects
- Prescription Opioids (Abuse) Health Effects
- These are proprietary names of particular drug products. Generic versions may also exist.
¡Hola! Me llamo Clara Mente y quiero darles la bienvenida a mi serie de boletines informativos que exploran la respuesta del cerebro a las drogas. En este ejemplar, investigaremos varios datos fascinantes sobre los opiáceos. Alguna de esta información fue descubierta recientemente por los científicos que lideran la investigación en este campo.
Si alguna vez viste la película "El Mago de Oz", entonces has visto la planta de la amapola. Esta planta es la fuente de un tipo de drogas llamadas opiáceos. Cuando Dorothy se acuesta en el campo de amapolas, cae en un sueño profundo.
Con razón que el nombre en latín de esta planta –Papaver somniferum– quiere decir "amapola somnífera" o "amapola que te da sueño".
Los opiáceos se fabrican del opio, que se deriva de la amapola. También se los conoce como narcóticos. Tal vez hayas oído de ciertas drogas como la heroína, la morfina o la codeína. Éstas son ejemplos de opiáceos.
Los opiáceos pueden producir una sensación rápida e intensa de placer, seguida por una sensación de bienestar y calma adormecedora. Pero también se pueden convertir en una adicción. Si alguien usa opiáceos una y otra vez, es probable que su cerebro comience a depender de estas drogas.
Después de años de experimentos, los científicos han descubierto cómo copiar (“clonar”) los genes que controlan la producción de los receptores de opiáceos. Ahora les será más fácil a los científicos hacer receptores de opiáceos y estudiar cómo los opiáceos afectan las células nerviosas.
Este descubrimiento puede llevar a otros hallazgos emocionantes tales como mejores tratamientos para la adicción a los opiáceos.
Los opiáceos actúan sobre diferentes partes del cerebro y del sistema nervioso
El tallo cerebral controla las cosas que tu cuerpo hace automáticamente, como respirar y toser. Los opiáceos actúan sobre el tallo cerebral para detener la tos y disminuir la respiración. (azul)
La espina dorsal transmite las señales de dolor del cuerpo. Al actuar en la espina dorsal, los opiáceos bloquean los mensajes de dolor y permiten que las personas soporten el dolor aún de lesiones graves. (amarillo)
El sistema límbico controla las emociones. Los opiáceos cambian al sistema límbico para producir sensaciones más intensas de placer, rebajamiento y felicidad. (rojo)
¿Qué les pasa a las personas y a sus cerebros cuando se vuelven adictos a los opiáceos? El uso de opiáceos por largo tiempo cambia cómo funcionan las células nerviosas del cerebro. Estas células se acostumbran tanto a los opiáceos que llegan a necesitar de ellos para poder funcionar normalmente.
Si se les quita el opiáceo a estas células nerviosas dependientes, muchas de ellas se vuelven hiperactivas. Eventualmente, estas células volverán a funcionar normalmente, pero mientras tanto, pueden causar una gran variedad de síntomas en el cerebro y en el resto del cuerpo. Éstos se conocen como síntomas del síndrome de abstinencia.
¿Alguna vez te ha dado gripe? Probablemente, tuviste síntomas como malestar, fiebre, sudoración, temblores o escalofríos. Éstos son parecidos a los síntomas del síndrome de abstinencia, excepto que estos últimos son mucho peores. ¡Uuuyyy! cuerpo.
Ésta es una manera de ilustrar lo difícil que es para las células funcionar sin la droga de la que dependen. Toma un papel e intenta dibujar una ilustración de una revista sin usar la mano que normalmente usas.
Las células nerviosas se pueden volver dependientes de los opiáceos.
Las células nerviosas dependientes de los opiáceos pueden perder su capacidad para transmitir mensajes normalmente.
Cómo responden las células nerviosas a los opiáceos
Hay lugares en ciertas células nerviosas del sistema límbico, el tallo cerebral y la espina dorsal, que reconocen a los opiáceos. Cuando estos sitios, llamados receptores de opiáceos, son estimulados por dicha droga, provocan una respuesta tanto en el cerebro como en el resto del cuerpo.
Los científicos han identificado tres tipos de receptores de opiáceos: delta, kappa y mu (denominados así por las letras griegas del mismo nombre). Cada uno de estos tipos de receptores está involucrado en diferentes funciones cerebrales. Por ejemplo, los receptores mu son los responsables por los efectos analgésicos (que alivian el dolor) de la droga opiácea llamada morfina.
¿Sabías que algunos opiáceos tienen usos médicos importantes? Son poderosos analgésicos y a veces los médicos los recetan para controlar la diarrea severa. Si miras la etiqueta del remedio para la tos, puedes encontrar que uno de los ingredientes es un opiáceo llamado codeína.
Cuando se usan adecuadamente para propósitos médicos, los opiáceos no producen una sensación de placer intenso, por lo que la probabilidad de que causen adicción en los pacientes es muy poca.
Tu cerebro produce su propia versión de los opiáceos, llamados endorfinas u opioides endógenos. Estas sustancias químicas actúan como los opiáceos, adhiriéndose a los receptores de opiáceos.
Tu cuerpo controla el dolor a través de los opioides endógenos. Si alguna vez te has sentido completamente relajado después de haber hecho mucho ejercicio, es probable que esa sensación haya sido el resultado de la liberación de esta sustancia química natural dentro de tu cerebro.
- September 04, 2013
This past Drug Facts Chat Day, teens from across the country submitted their questions about drug abuse to NIDA scientists.
A teen from Walter Johnson High School in Maryland asked, “What types of opioids are there?”
In general, opioids are psychoactive chemicals that work by binding to opioid receptors in the body. These receptors are found principally in the central and peripheral nervous system as well as the gastrointestinal tract and can produce both the good and bad effects of opioid use.
Many teens don’t know that there are illegal opioids (like heroin) as well as legal opioids that are prescribed for pain relief (like hydrocodone, which has the brand name of Vicodin). This is why common painkillers like Vicodin are so often abused—because they provide a “high” while relieving pain.
Here are the main types of opioids:
- Natural opiates are alkaloids, nitrogen-containing base chemical compounds that occur in plants such as in the resin of the opium poppy. Natural opiates include morphine, codeine, and thebaine.
- Semi-synthetic opioids are opioids created in labs from natural opiates. Semi-synthetic opioids include hydromorphone, hydrocodone, and oxycodone (the prescription drug OxyContin), as well as heroin, which is made from morphine.
- Fully synthetic opioids are opioids that are completely manmade, including fentanyl, pethidine, levorphanol, methadone, tramadol, and dextropropoxyphene.
Some opioids (e.g., morphine, codeine, OxyContin) are used by doctors to treat various things, such as pain after surgery. But opioids also have addictive properties and negative health effects that make them dangerous when abused.
Do you have other questions about types of drugs? Tell us in comments.Tags:OpioidsComments posted to the Drugs & Health Blog are from the general public and may contain inaccurate information. They do not represent the views of NIDA or any other federal government entity.
- July 16, 2014
Learn more about the different types of opioids in this updated post from 2013.
During the 2013 Drug Facts Chat Day, teens from across the country submitted their questions about drug abuse to NIDA scientists. A teen from Walter Johnson High School in Maryland asked:
“What types of opioids are there?”
Opioids are psychoactive chemicals that occur naturally (in the resin of the poppy plant) or can be made in a laboratory. They work by binding to opioid receptors in the central and peripheral nervous system and the gastrointestinal tract.
There are illegal opioids (like heroin) as well as legal opioids that are prescribed for pain relief (like hydrocodone, which has the brand name of Vicodin). In fact, there is a dangerous trend where people that have become addicted to prescription opioids begin using heroin because it’s cheaper to get.
There are 3 main types of opioids:
- Natural opiates are alkaloids, nitrogen-containing base chemical compounds that occur in plants such as the opium poppy. Natural opiates include morphine, codeine, and thebaine.
- Semi-synthetic/manmade opioids are created in labs from natural opiates. Semi-synthetic opioids include hydromorphone, hydrocodone, and oxycodone (the prescription drug OxyContin), as well as heroin, which is made from morphine.
- Fully synthetic/manmade opioids are completely manmade, including fentanyl, pethidine, levorphanol, methadone, tramadol, and dextropropoxyphene.
Prescription opioids (e.g., morphine, codeine, OxyContin) are prescribed by doctors to treat pain and provide millions of people with much needed relief when used as prescribed. However, opioids can produce a “high,” so some people abuse them. This has led to thousands of overdose deaths. In 2008, prescription opioids were responsible for 14,800 overdose deaths and in 2009, for more than 475,000 emergency room visits.
Do you have other questions about types of drugs? Tell us in comments.Categories:Real Teens Ask About DrugsComments posted to the Drugs & Health Blog are from the general public and may contain inaccurate information. They do not represent the views of NIDA or any other federal government entity.