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  • Hallucinogens

    Hallucinogens are drugs which cause altered states of perception and feeling and which can produce flashbacks. They include natural substances, such as mescaline and psilocybin that come from plants (cactus and mushrooms), and chemically manufactured ones, such as LSD and MDMA (ecstasy). LSD is manufactured from lysergic acid, which is found in ergot, a fungus that grows on rye and other grains. MDMA is a synthetic mind-altering drug with both stimulant and hallucinogenic properties. Although not a true hallucinogen in the pharmacological sense, PCP causes many of the same effects as hallucinogens and so is often included with this group of drugs. Hallucinogens have powerful mind-altering effects. They can change how the brain perceives time, everyday reality, and the surrounding environment. They affect regions and structures in the brain that are responsible for coordination, thought processes, hearing, and sight. They can cause people who use them to hear voices, see images, and feel sensations that do not exist. Researchers are not certain that brain chemistry permanently changes from hallucinogen use, but some people who use them appear to develop chronic mental disorders. PCP and MDMA can be addictive; whereas LSD, psilocybin, and mescaline are not.

    Research has provided many clues about how hallucinogens act in the brain to cause their powerful effects. However, because there are different types of hallucinogens and their effects are so widespread, there is still much that is unknown. The following paragraphs describe some of what is known about this diverse group of drugs.

  • La búsqueda continúa

    Clara Mente sigue explorando

    La verdad es que todavía hay mucho que los científicos no saben sobre los efectos de los alucinógenos sobre el cerebro. Tal vez algún día tú serás quien logre el próximo gran descubrimiento.

    Hasta entonces, acompáñame en otros boletines informativos de mi serie, en los que exploramos cómo las drogas afectan al cerebro y al sistema nervioso.

    Explorando la Mente es una serie producida por el Instituto Nacional sobre el Abuso de Drogas (NIDA, por sus siglas en inglés), parte de los Institutos Nacionales de la Salud. Estos materiales son del dominio público y se pueden reproducir sin permiso. Se agradece citar la fuente.

    Publicación NIH No. 06-3858 (s). Impresa en el 2006.

    Instituto Nacional sobre el Abuso de Drogas
    Institutos Nacionales de la Salud
    Departamento de Salud y Servicios Humanos de los EE.UU.

  • Mechanism of Action

    Mechanism of Action

    LSD binds to and activates a specific receptor for the neurotransmitter serotonin. Normally, serotonin binds to and activates its receptors and then is taken back up into the neuron that released it. In contrast, LSD binds very tightly to the serotonin receptor, causing a greater than normal activation of the receptor. Because serotonin has a role in many of the brain's functions, activation of its receptors by LSD produces widespread effects, including rapid emotional swings, and altered perceptions, and if taken in a large enough dose, delusions and visual hallucinations.

    MDMA, which is similar in structure to Methamphetamine and mescaline, causes serotonin to be released from neurons in greater amounts than normal. Once released, this serotonin can excessively activate serotonin receptors. Scientists have also shown that MDMA causes excess dopamine to be released from dopamine-containing neurons. Particularly alarming is research in animals that has demonstrated that MDMA can damage serotonin-containing neurons. MDMA can cause confusion, depression, sleep problems, drug craving, and severe anxiety.

    PCP, which is not a true hallucinogen, can affect many neurotransmitter systems. It interferes with the functioning of the neurotransmitter glutamate, which is found in neurons throughout the brain. Like many other drugs, it also causes dopamine to be released from neurons into the synapse. At low to moderate doses, PCP causes altered perception of body image, but rarely produces visual hallucinations. PCP can also cause effects that mimic the primary symptoms of schizophrenia, such as delusions and mental turmoil. People who use PCP for long periods of time have memory loss and speech difficulties.

    The following activities, when used along with the magazine on hallucinogens, will help explain to students how these substances change the brain and the body.

  • Salvia

    Salvia (Salvia divinorum) is an herb in the mint family native to southern Mexico. It is used to produce hallucinogenic experiences.

    Salvia, an herb common to southern Mexico, Central, and South America.

    How Is Salvia Used?

    Traditionally, S. divinorum has been ingested by chewing fresh leaves or by drinking their extracted juices. The dried leaves of S. divinorum can also be smoked in rolled cigarettes or pipes or vaporized and inhaled.

    Although information about salvia is limited, its use may be driven in part by drug-related videos and information on Internet sites. Because of the nature of the drug’s effects—brief hallucinogenic experiences that mimic psychosis—it is more likely to be used in individual experimentation than as a social or party drug.

    How Does Salvia Affect the Brain?

    The main active ingredient in salvia, salvinorin A, is a potent activator of nerve cell targets called kappa opioid receptors. (These receptors differ from the receptors activated by commonly known opioid drugs such as heroin and morphine.) Although salvia is generally considered a hallucinogen, it does not act at serotonin receptors that are activated by other hallucinogens like LSD or psilocybin, and its effects are reported by experienced users to be different from those drugs.

    Is Salvia Illegal?

    Salvia currently is not a drug regulated by the Controlled Substances Act, but several States and countries have passed legislation to regulate its use.

    Subjective effects of salvia use have been described as intense but short-lived, appearing in less than 1 minute and lasting less than 30 minutes. They include psychedelic-like changes in visual perception, mood and body sensations, emotional swings, feelings of detachment, and a highly modified perception of external reality and the self, leading to a decreased ability to interact with one's surroundings. This last effect has prompted concern about the dangers of driving under the influence of salvinorin.

    What Are the Other Health Effects of Salvia?

    The psychological or physical health effects of salvia use have not been investigated systematically, and consequences of long-term use are not known. Experiments in rodents demonstrated deleterious effects of salvinorin A on learning and memory, but there is little evidence of salvia causing dependence or long-term psychiatric problems in humans.

    Learn More

    For additional information on salvia, please refer to the following sources on NIDA’s Web site:

  • Activity One

    Activity One


    The student will learn how hallucinogens cause visual misperception and hallucinations.


    Have students draw a bull's-eye onto a sheet of unruled white paper. Make a small "X" at the center of another sheet of paper. Now, have the students stare at the bull's-eye for about 20 seconds and then quickly shift their focus to the "X". Students will find that an after-image of the bull's-eye will appear. Explain that after-images are a class of optical illusions, which have some similarity to hallucinations. Have students search the Internet and other sources for information about drug-induced hallucinations and prepare a report summarizing their findings.

  • Activity Two

    Activity Two


    The student will learn that hallucinogens cause other sensory misperceptions.


    Fill one bowl with warm water, another with cold water, and a third with water at room temperature. First, have the students place the fingers of one hand in the warm water. Wait 60 seconds. Then have them place their fingers in the room temperature water and describe the temperature of the water (feels cool). Then have the students place their fingers of the other hand in the cold water. Wait 60 seconds. Then have them place their fingers in the room temperature water and describe the temperature of the water (feels hot). Remind students that hallucinogens can affect the way we perceive reality.

  • DrugFacts: Hallucinogens - LSD, Peyote, Psilocybin, and PCP

    Hallucinogenic compounds found in some plants and mushrooms (or their extracts) have been used—mostly during religious rituals—for centuries. Almost all hallucinogens contain nitrogen and are classified as alkaloids. Many hallucinogens have chemical structures similar to those of natural neurotransmitters (e.g., acetylcholine-, serotonin-, or catecholamine-like). While the exact mechanisms by which hallucinogens exert their effects remain unclear, research suggests that these drugs work, at least partially, by temporarily interfering with neurotransmitter action or by binding to their receptor sites. This DrugFacts will discuss four common types of hallucinogens:

    • LSD (d-lysergic acid diethylamide) is one of the most potent mood-changing chemicals. It was discovered in 1938 and is manufactured from lysergic acid, which is found in ergot, a fungus that grows on rye and other grains.
    • Peyote is a small, spineless cactus in which the principal active ingredient is mescaline. This plant has been used by natives in northern Mexico and the southwestern United States as a part of religious ceremonies. Mescaline can also be produced through chemical synthesis.
    • Psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine) is obtained from certain types of mushrooms that are indigenous to tropical and subtropical regions of South America, Mexico, and the United States. These mushrooms typically contain less than 0.5 percent psilocybin plus trace amounts of psilocin, another hallucinogenic substance.
    • PCP (phencyclidine) was developed in the 1950s as an intravenous anesthetic. Its use has since been discontinued due to serious adverse effects.

    How Are Hallucinogens Abused?

    The very same characteristics that led to the incorporation of hallucinogens into ritualistic or spiritual traditions have also led to their propagation as drugs of abuse. Importantly, and unlike most other drugs, the effects of hallucinogens are highly variable and unreliable, producing different effects in different people at different times. This is mainly due to the significant variations in amount and composition of active compounds, particularly in the hallucinogens derived from plants and mushrooms. Because of their unpredictable nature, the use of hallucinogens can be particularly dangerous.

    LSD is sold in tablets, capsules, and, occasionally, liquid form; thus, it is usually taken orally. LSD is often added to absorbent paper, which is then divided into decorated pieces, each equivalent to one dose. The experiences, often referred to as “trips,” are long; typically, they end after about 12 hours.

    Peyote: The top of the peyote cactus, also referred to as the crown, consists of disc-shaped buttons that are cut from the roots and dried. These buttons are generally chewed or soaked in water to produce an intoxicating liquid. The hallucinogenic dose of mescaline is about 0.3 to 0.5 grams, and its effects last about 12 hours. Because the extract is so bitter, some individuals prefer to prepare a tea by boiling the cacti for several hours.

    Psilocybin: Mushrooms containing psilocybin are available fresh or dried and are typically taken orally. Psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine) and its biologically active form, psilocin (4-hydroxy-N,N-dimethyltryptamine), cannot be inactivated by cooking or freezing preparations. Thus, they may also be brewed as a tea or added to other foods to mask their bitter flavor. The effects of psilocybin, which appear within 20 minutes of ingestion, last approximately 6 hours.

    PCP is a white crystalline powder that is readily soluble in water or alcohol. It has a distinctive bitter chemical taste. PCP can be mixed easily with dyes and is often sold on the illicit drug market in a variety of tablet, capsule, and colored powder forms that are normally snorted, smoked, or orally ingested. For smoking, PCP is often applied to a leafy material such as mint, parsley, oregano, or marijuana. Depending upon how much and by what route PCP is taken, its effects can last approximately 4–6 hours.

    How Do Hallucinogens Affect the Brain?

    LSD, peyote, psilocybin, and PCP are drugs that cause hallucinations, which are profound distortions in a person’s perception of reality. Under the influence of hallucinogens, people see images, hear sounds, and feel sensations that seem real but are not. Some hallucinogens also produce rapid, intense emotional swings. LSD, peyote, and psilocybin cause their effects by initially disrupting the interaction of nerve cells and the neurotransmitter serotonin.1 Distributed throughout the brain and spinal cord, the serotonin system is involved in the control of behavioral, perceptual, and regulatory systems, including mood, hunger, body temperature, sexual behavior, muscle control, and sensory perception. On the other hand, PCP acts mainly through a type of glutamate receptor in the brain that is important for the perception of pain, responses to the environment, and learning and memory.

    There have been no properly controlled research studies on the specific effects of these drugs on the human brain, but smaller studies and several case reports have been published documenting some of the effects associated with the use of hallucinogens.

    LSD: Sensations and feelings change much more dramatically than the physical signs in people under the influence of LSD. The user may feel several different emotions at once or swing rapidly from one emotion to another. If taken in large enough doses, the drug produces delusions and visual hallucinations. The user’s sense of time and self is altered. Experiences may seem to “cross over” different senses, giving the user the feeling of hearing colors and seeing sounds. These changes can be frightening and can cause panic. Some LSD users experience severe, terrifying thoughts and feelings of despair, fear of losing control, or fear of insanity and death while using LSD.

    LSD users can also experience flashbacks, or recurrences of certain aspects of the drug experience. Flashbacks occur suddenly, often without warning, and may do so within a few days or more than a year after LSD use. In some individuals, the flashbacks can persist and cause significant distress or impairment in social or occupational functioning, a condition known as hallucinogen-induced persisting perceptual disorder (HPPD).

    Most users of LSD voluntarily decrease or stop its use over time. LSD is not considered an addictive drug since it does not produce compulsive drug-seeking behavior. However, LSD does produce tolerance, so some users who take the drug repeatedly must take progressively higher doses to achieve the state of intoxication that they had previously achieved. This is an extremely dangerous practice, given the unpredictability of the drug. In addition, cross-tolerance between LSD and other hallucinogens has been reported.

    Peyote: The long-term residual psychological and cognitive effects of mescaline, peyote’s principal active ingredient, remain poorly understood. A recent study found no evidence of psychological or cognitive deficits among Native Americans that use peyote regularly in a religious setting.2 It should be mentioned, however, that these findings may not generalize to those who repeatedly abuse the drug for recreational purposes. Peyote abusers may also experience flashbacks.

    Psilocybin: The active compounds in psilocybin-containing “magic” mushrooms have LSD-like properties and produce alterations of autonomic function, motor reflexes, behavior, and perception.3 The psychological consequences of psilocybin use include hallucinations, an altered perception of time, and an inability to discern fantasy from reality. Panic reactions and psychosis also may occur, particularly if a user ingests a large dose. Long-term effects such as flashbacks, risk of psychiatric illness, impaired memory, and tolerance have been described in case reports.

    PCP: The use of PCP as an approved anesthetic in humans was discontinued in 1965 because patients often became agitated, delusional, and irrational while recovering from its anesthetic effects. PCP is a “dissociative drug,” meaning that it distorts perceptions of sight and sound and produces feelings of detachment (dissociation) from the environment and self. First introduced as a street drug in the 1960s, PCP quickly gained a reputation as a drug that could cause bad reactions and was not worth the risk. However, some abusers continue to use PCP due to the feelings of strength, power, and invulnerability as well as a numbing effect on the mind that PCP can induce. Among the adverse psychological effects reported are—

    • Symptoms that mimic schizophrenia, such as delusions, hallucinations, paranoia, disordered thinking, and a sensation of distance from one’s environment.
    • Mood disturbances: Approximately 50 percent of individuals brought to emergency rooms because of PCP-induced problems—related to use within the past 48 hours—report significant elevations in anxiety symptoms.4
    • People who have abused PCP for long periods of time have reported memory loss, difficulties with speech and thinking, depression, and weight loss. These symptoms can persist up to one year after stopping PCP abuse.
    • Addiction: PCP is addictive—its repeated abuse can lead to craving and compulsive PCP-seeking behavior, despite severe adverse consequences.

    What Other Adverse Effects Do Hallucinogens Have on Health?

    Unpleasant adverse effects as a result of the use of hallucinogens are not uncommon. These may be due to the large number of psychoactive ingredients in any single source of hallucinogen.3

    • LSD: The effects of LSD depend largely on the amount taken. LSD causes dilated pupils; can raise body temperature and increase heart rate and blood pressure; and can cause profuse sweating, loss of appetite, sleeplessness, dry mouth, and tremors.
    • Peyote: Its effects can be similar to those of LSD, including increased body temperature and heart rate, uncoordinated movements (ataxia), profound sweating, and flushing. The active ingredient mescaline has also been associated, in at least one report, to fetal abnormalities.5
    • Psilocybin: It can produce muscle relaxation or weakness, ataxia, excessive pupil dilation, nausea, vomiting, and drowsiness. Individuals who abuse psilocybin mushrooms also risk poisoning if one of many existing varieties of poisonous mushrooms is incorrectly identified as a psilocybin mushroom.
    • PCP: At low-to-moderate doses, physiological effects of PCP include a slight increase in breathing rate and a pronounced rise in blood pressure and pulse rate. Breathing becomes shallow; flushing and profuse sweating, generalized numbness of the extremities, and loss of muscular coordination may occur.

      At high doses, blood pressure, pulse rate, and respiration drop. This may be accompanied by nausea, vomiting, blurred vision, flicking up and down of the eyes, drooling, loss of balance, and dizziness. PCP abusers are often brought to emergency rooms because of overdose or because of the drug’s severe untoward psychological effects. While intoxicated, PCP abusers may become violent or suicidal and are therefore dangerous to themselves and others. High doses of PCP can also cause seizures, coma, and death (though death more often results from accidental injury or suicide during PCP intoxication). Because PCP can also have sedative effects, interactions with other central nervous system depressants, such as alcohol and benzodiazepines, can also lead to coma.

    What Treatment Options Exist?

    Treatment for alkaloid hallucinogen (such as psilocybin) intoxication—which is mostly symptomatic—is often sought as a result of bad “trips,” during which a patient may, for example, hurt him- or herself.6 Treatment is usually supportive: provision of a quiet room with little sensory stimulation. Occasionally, benzodiazepines are used to control extreme agitation or seizures.

    There is very little published data on treatment outcomes for PCP intoxication. Doctors should consider that acute adverse reactions may be the result of drug synergy with alcohol.7 Current research efforts to manage a life-threatening PCP overdose are focused on a passive immunization approach through the development of anti-PCP antibodies.8 There are no specific treatments for PCP abuse and addiction, but inpatient and/or behavioral treatments can be helpful for patients with a variety of addictions, including that to PCP.

    How Widespread Is the Abuse of Hallucinogens?

    According to the 2013 National Survey on Drug Use and Health (NSDUH)*, more than 1.1 million people aged 12 or older reported using hallucinogens within the past 12 months.


    In 2013, more than 24.8 million people aged 12 or older reported they had used LSD in their lifetime (9.4 percent) according to NSDUH. More than 1.1 million people had used the drug in the past year. Between 2012 and 2013, the number of past-year initiates of LSD increased only slightly.

    Peyote and Psilocybin

    It is difficult to gauge the extent of use of these hallucinogens because most data sources that quantify drug use exclude these drugs.


    In 2013, 6.5 million people aged 12 or older reported that they had used PCP in their lifetime (2.5 percent) according to NSDUH. However, only 90,000 people reported use in the past year—a decrease from 172,000 in 2012.

    Learn More

    For more information on hallucinogens, please visit

    Other Data Sources

    * NSDUH (formerly known as the National Household Survey on Drug Abuse) is an annual survey of Americans age 12 and older conducted by the Substance Abuse and Mental Health Services Administration, U.S. Department of Health and Human Services. This survey is available on line at


    1. Fantegrossi WE, Murnane KS, Reissig CJ. The behavioral pharmacology of hallucinogens. Biochem Pharmacol. 2008;75(1):17-33.
    2. Halpern JH, Sherwood AR, Hudson JI, Yurgelun-Todd D, Pope HG Jr. Psychological and cognitive effects of long-term peyote use among Native Americans. Biol Psychiatry. 2005;58(8):624-631.
    3. Cunningham N. Hallucinogenic plants of abuse. Emerg Med Australas. 2008;20(2):167-174.
    4. Yago,KB, Pitts, FN, Burgoyne, RW, Aniline, O, Yago, LS, Pitts AF. The urban epidemic of phencyclidine (PCP) use: Clinical and laboratory evidence from a public psychiatric hospital emergency service. J Clin Psychiatry. 1981;42:193-196.
    5. Gilmore HT. Peyote use during pregnancy. S D J Med. 2001;54(1):27-29.
    6. Attema-de Jonge ME, Portier CB, Franssen EJ. Automutilation after consumption of hallucinogenic mushrooms. Ned Tijdschr Geneeskd. 2007;151(52):2869-2872.
    7. Schwartz RH, Smith DE. Clin Pediatr (Phila). 1988;27(2):70-73.
    8. Kosten T, Owens SM. Immunotherapy for the treatment of drug abuse. Pharmacol Ther. 2005;108(1):76-85.
  • The Brain's Response to Hallucinogens

    Hi, my name’s Sara Bellum. Welcome to my magazine series exploring the brain’s response to drugs. In this issue, we’ll investigate the fascinating facts about hallucinogens.

    Hallucinogens cause people to experience—you guessed it—hallucinations, imagined experiences that seem real.

    The word “hallucinate” comes from Latin words meaning “to wander in the mind.” No wonder some people refer to hallucinating as “tripping.”

    The “trips” caused by hallucinogens can last for hours. Parts of these trips can feel really good, and other parts can feel really terrible.

    Hallucinogens powerfully affect the brain, distorting the way our five senses work and changing our impressions of time and space. When people use these drugs a lot they may have a hard time concentrating, communicating, or telling the difference between reality and illusion.

  • Activity Three

    Activity Three


    The student will learn vocabulary and facts associated with hallucinogens.


    Instruct the students to complete the Hallucinogens Word Puzzle (below). The puzzle and solution to the puzzle are included in the guide.

    Word Puzzle

    Blank word puzzle


    Word Puzzle Answers

    Word puzzle with answers

  • Where Do Hallucinogens Come From?

    Some hallucinogens can be found in plants. Mescaline comes from a cactus called peyote. And certain mushrooms, also known as “magic” mushrooms, are hallucinogens.

    But many hallucinogens are chemicals that don’t occur in nature. Some examples are:

    • LSD, also called acid
    • MDA, also called the “love drug,” related to the stimulant amphetamine
    • MDMA, known as ecstasy, also related to amphetamine
    • PCP, often called angel dust
  • How Hallucinogens Affect Your Senses

    Your brain controls all of your perceptions—the way you see, hear, smell, taste, and feel. How does your brain communicate with the rest of your body? Chemical messengers transmit information from nerve cell to nerve cell in the body and the brain. Messages are constantly being sent back and forth with amazing speed.

    Your nerve cells are called neurons, and their chemical messengers are called neurotransmitters. When neurotransmitters attach to special places on nerve cells (called receptors), they cause changes in the nerve cells.

    This communication system can be disrupted by chemicals like hallucinogens, and the results are changes in the way you sense the world around you.

  • La respuesta del cerebro a los alucinógenos

    Clara Mente explorando peyotes desde un avión

    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 alucinógenos. Alguna de esta información fue descubierta recientemente por los científicos que lideran la investigación en este campo.

    Los alucinógenos hacen que las personas tengan –¡lo adivinaste!– alucinaciones. Las alucinaciones son experiencias imaginadas que parecen ser reales. La palabra "alucinar" viene de palabras en latín que significan "vagando por la mente".

    Con razón que algunas personas se refieren a tener alucinaciones como "tomar un viaje".

    Los "viajes" causados por los alucinógenos pueden durar varias horas. Partes de estos viajes pueden hacerte sentir muy bien y otras partes pueden hacerte sentir muy mal.

    Los alucinógenos afectan al cerebro de una manera muy poderosa, distorsionando la manera en que los cinco sentidos funcionan y cambiando nuestra percepción del tiempo y del espacio. Las personas que usan estas drogas a menudo pueden tener dificultad para concentrarse, comunicarse o para distinguir la diferencia entre la realidad y una ilusión.

  • How MDMA and MDA Affect Your Brain

    MDMA and MDA cause neurons to release a neurotransmitter called serotonin, which can overactivate serotonin receptors. Serotonin is important to many types of nerve cells, including cells that receive sensory information and cells that control mood, sleep, and memory. Animal studies have taught us that MDMA and MDA can damage fibers from these nerve cells. And even though some of these fibers grow back, they don’t grow back normally. They can wind up in places where they don’t belong.

  • ¿De dónde vienen los alucinógenos?

    Un cacto alucinógeno

    Algunos alucinógenos se encuentran en las plantas. La mescalina viene de un cacto llamado peyote. Ciertos hongos, conocidos como hongos mágicos, son alucinógenos.

    Pero muchos de los alucinógenos son sustancias químicas que no se encuentran en la naturaleza. Algunos ejemplos incluyen:

    • La LSD, también conocida como ácido;
    • La MDA, una anfetamina que es un tipo de droga que investigo en más detalle en mi boletín informativo sobre estimulantes;
    • La MDMA, una anfetamina conocida como éxtasis; y
    • La PCP (fenciclidina), a menudo llamada polvo de ángel.
  • Cómo los alucinógenos afectan tus sentidos

    Una célula nerviosa

    Tu cerebro controla cómo percibes las cosas, es decir, cómo ves, oyes, hueles, saboreas y cómo sientes. ¿Cómo se comunica tu cerebro con el resto de tu cuerpo? Los mensajeros químicos transmiten información de una célula nerviosa a otra tanto en el cuerpo como en el cerebro. Estos mensajes son enviados constantemente de un lado a otro a una velocidad impresionante.

    Tus células nerviosas se llaman neuronas y sus mensajeros químicos se llaman neurotransmisores. Cuando los neurotransmisores se adhieren a lugares especiales en las neuronas (llamados receptores) causan cambios en estas neuronas.

    Este sistema de comunicación puede ser interrumpido por sustancias químicas como los alucinógenos y los resultados son cambios en la manera en que percibes el mundo a tu alrededor.

  • LSD: The Most Commonly Used Hallucinogen

    LSD causes its effects mainly by activating one type of receptor for serotonin. Because serotonin has a role in many important functions, LSD use can have many effects. These may include sleeplessness, trembling, and raised heart rate and blood pressure.

    LSD users may feel several emotions at once (including extreme terror), and their senses may seem to get crossed—giving the feeling of hearing colors and seeing sounds.

    Even a tiny speck of LSD can trigger these effects. And LSD has an unusual “echo”: many users have flashbacks—sudden repetitions of their LSD experiences—days or months after they stop using the drug.

    Have your perceptions been

    altered upside down

    Hallucinogens can change the way you see things. The experience is a little like looking at the optical illusion above.

  • Un descubrimiento reciente

    Clara Mente reconectando las neuronas

    La MDMA y la MDA hacen que las neuronas liberen un neurotransmisor llamado serotonina. La serotonina es importante para muchos tipos de células nerviosas, incluyendo las células que reciben información sensorial y las células que controlan el sueño y las emociones. La serotonina que ha sido liberada puede sobreactivar los receptores de serotonina. En los animales se ha demostrado que la MDMA y la MDA dañan y destruyen las fibras nerviosas de aquellas neuronas que contienen serotonina. Esto puede ser un gran problema porque las neuronas que almacenan serotonina juegan un papel en varias cosas como en el estado de ánimo, el sueño y el control del ritmo cardiaco.

    Los científicos han descubierto recientemente que las neuronas con serotonina que han sido dañadas sí pueden hacer crecer sus fibras nuevamente, pero que éstas no vuelven a crecer normalmente. Es posible que las fibras vuelvan a crecer en áreas del cerebro donde normalmente no lo harían, mientras que no logran crecer en otras áreas del cerebro donde sí deberían encontrarse. Los nuevos patrones de crecimiento pueden causar cambios en el estado de ánimo, en el aprendizaje y en la memoria.

  • The Search Continues

    The truth is, there’s still a whole lot that scientists don’t know about the effects of hallucinogens on the brain. Maybe someday you’ll make the next big discovery.

    Until then, join me—Sara Bellum—in the other magazines in my series, as we explore how drugs affect the brain and nervous system.

    Mind Over Matter is produced by the National Institute on Drug Abuse, National Institutes of Health. These materials are in the public domain and may be reproduced without permission. Citation of the source is appreciated. NIH Publication No. 03-3858. Printed 1997. Reprinted 1998, 2000, 2003.

  • Cómo actúa la PCP sobre el cerebro

    La PCP no deja que ocurran las acciones que normalmente toman lugar cuando un neurotransmisor llamado glutamato, se adhiere a su receptor en el cerebro. También interrumpe las acciones de otros neurotransmisores.

    Los efectos de esta droga son impredecibles. Por ejemplo, puede hacer que algunas personas tengan alucinaciones y se vuelvan agresivas, mientras que a otras les puede dar somnolencia y se vuelven pasivas. También causa adicción.