Drugs

1. Drugs Module 22

2. What are psychoactive drugs? • chemical substances that alters perceptions, mood, or behavior • induce an altered state of consciousness • 3 most common: • caffeine • alcohol • nicotine

3. What is dependence? • physiological and/or psychological need for a drug • withdrawal follows if the drug is discontinued When does dependence become addiction? • when the drug seriously disrupts a person’s ability to function in everyday life

4. Withdrawal • discomfort & distress that follow when a person who is dependent on a drug discontinues use • symptoms are usually the reverse of the drug’s effects • example: heroin • intended effect – euphoria, relaxation, slowed breathing • withdrawal – depression, restlessness, rapid breathing

5. Tolerance • reduced responsiveness to a drug • user must increase dosage to achieve effects previously obtained by lower doses of the drug

6. Drugs and NeurotransmissionHow do psychoactive drugs work?

7. Neurotransmission • process where neurons communicate with each other • psychoactive drugs interfere with normal neurotransmission

8. 3 ways drugs affect neurotransmission: • Binding with receptors • mimicking neurotransmitter’s effect • example: morphine mimics endorphins • Blocking receptor site • preventing neurotransmitter’s binding • example:Botulin poisoning (paralyzes) • Blocking reuptake • intensifies neurotransmitter’s effect • example: cocaine blocks reuptake of dopamine (affects mood) increasing the amount in the synapses

9. Drug Classifications

10. Marijuana • Description: • derived from hemp plant • lowers inhibitions & produces feelings of relaxation and mild euphoria • Impact on Neurotransmission: • Active ingredient: THC (delta-9-tetrahydrocannabinol) • binds to cannabinoid receptor sites for neurotransmitter anandamide (pain relief, working memory, pleasure, eating, motivation) • binds to receptor sites for dopamine (pleasure/euphoria) & triggers their release

11. Marijuana • Physical & Psychological Impact: • lowers inhibitions & produces feelings of relaxation and mild euphoria • Health Concerns: • 9% of users become addicted • withdrawal symptoms: irritability, sleeplessness, decreased appetite, anxiety, & drug craving • disrupts short-term memory (activity in hippocampus is reduced) • Interferes with normal functioning of the cerebellum (short-term) • lung damage from smoke Leaves, stems, resin, and flowers form the hemp plant

12. Medical Marijuana (currently legal in 16 states & D.C.)

13. Hallucinogens • Description: • distort perceptions & cause sensory images in the absence of sensory input • Impact on Neurotransmission: • LSD (fungus that grows on grain)- stimulation of serotonin (mood, hunger, body temperature, sexual behavior, and muscle control) receptors on neurons • Ecstasy – blocks the reuptake of serotonin (mood/pleasure) intensifying its effect; brain is depleted of its serotonin supply & depression is a common after-effect

14. Hallucinogens • Physical & Psychological Impact: • LSD – visual hallucinations, detachment from reality, panic, sense of heightened understanding • Ecstasy – hallucinations, rushes of exhilaration (stimulant),physical sensitivity, lowers inhibitions, euphoria, paranoia • Health Concerns: • LSD – tolerance develops rapidly, rapid heartbeat & high blood pressure, “bad trips” – paranoia, panic delusions, dangerous behavior • Ecstasy – dehydration & heat exhaustion (club drug), increased body temp & blood pressure, nausea blurred, vision, teeth/jaw clenching

15. Stimulants • Description: • excite neural activity of CNS & speeds up body functions • Impact on Neurotransmission: • Caffeine – mimics adenosine (causes drowsiness) & blocks receptor sites • Nicotine – mimics acetylcholine (learning, memory, muscle movement, energy) & binds to receptor sites; body must create more receptor sites; endorphin (pain killers) production • Cocaine – blocks reuptake of dopamine (pleasure/emotion) • Amphetamines (prescription stimulants, ADHD) - mimics adrenaline (forces release of stored adrenaline); increases dopamine (pleasure/ motivation/ attention) – also with Methamphetamines (over time destroys dopamine receptors – can’t feel pleasure, can regrow over years); release adrenaline Coca plant

16. Stimulants • Physical & Psychological Impact: • All – increase blood pressure & heart rate, faster respiration • Caffeine – increases energy/alertness, reduces fine motor coordination • Nicotine – arousal, relaxation, sense of well being • Cocaine – euphoria, energy, increases body temperature • Amphetamines – euphoria, suppress appetite, increase focus & attention • Health Concerns: • Caffeine – insomnia, nervousness, headaches, dizziness, lethal in massive doses (abnormal heart rhythms, seizures, breathing in vomit) • Nicotine – death - heart/lung disease, stroke • Cocaine - heart attacks, respiratory failure, strokes, seizures, abdominal pain, nausea; sudden death on first use (rare) • Amphetamines – malnutrition, in high doses cardiovascular complications ( heart attack & stroke), amphetamine psychosis • Methamphetamines – stroke, dementia, reduced motor speed, impaired cognitive abilities, increased sex drive, lower inhibitions

17. Caffeine& the Body

18. Depressants • Description: • reduce neural activity & slow body functioning • Impact on Neurotransmission: • Alcohol – binds to receptors for acetylcholine, serotonin, GABA (reduces neural activity), increases release of dopamine • Sedatives (tranquilizers) • Barbiturates & Benzodiazepines – binds to GABA receptors

19. Depressants • Physical & Psychological Impact: • Alcohol – relaxation, reduced tension, lowered inhibitions, impairs concentration, slows reflexes • Sedatives – reduce anxiety or induce sleep • Health Concerns: • Alcohol – vomiting, breathing difficulties, unconsciousness, coma, impairs memory (suppresses REM sleep) damage to frontal lobes, kidney failure, vitamin B-1 deficiency, Fetal Alcohol Syndrome (alcohol use when pregnant) • Sedatives: • Barbiturates– lethal in overdose, impair memory & judgment • Benzodiazepines– dependency Fetal Alcohol Syndrome

20. Opiates • Description: • depress neural activity & temporarily lessen pain and anxiety • Impact on Neurotransmission: • Morphine (derived from poppy plant) & Heroin (made from morphine) – mimic endorphins and binds to opioid receptors (pain, reward, critical life functions like breathing)

21. Opiates • Physical & Psychological Impact: • Heroin & Morphine – rush of euphoria, relief from pain, clouded mental functioning • Health Concerns: • Heroin – overdose – stop breathing, use of needles (HIV/AIDS), liver or kidney failure • Morphine – dependence leading to addiction, cessation of breathing, nausea, vomiting, constipation

22. Drug Quick Write Without using your notes: • Choose onespecific psychoactive drug from the five major drug categories we have studied. Explain how that drug affects neurotransmission and behaviors.

23. Drug Neurotransmission Review anandamide & dopamine serotonin adenosine acetylcholine dopamine adrenaline acetylcholine, serotonin, GABA GABA endorphins

24. Drug Classifications Hallucinogen Stimulants Depressants Opiates Marijuana