Types of Psychoactive Drugs How they work

4 WAYS THAT DRUGS WORK: 1.Some drugs, like heroin and LSD, mimic the effects of a natural neurotransmitter 2.Others, like PCP, block receptors and thereby prevent neuronal messages from getting through 3.Some, like cocaine, interfere with the molecules that are responsible for transporting neurotransmitters back into the neurons that released them 4.Finally, some drugs, such as Methamphetamine, act by causing neurotransmitters to be released in greater amounts than normal 4 WAYS THAT DRUGS WORK: 1.Some drugs, like heroin and LSD, mimic the effects of a natural neurotransmitter 2.Others, like PCP, block receptors and thereby prevent neuronal messages from getting through 3.Some, like cocaine, interfere with the molecules that are responsible for transporting neurotransmitters back into the neurons that released them 4.Finally, some drugs, such as Methamphetamine, act by causing neurotransmitters to be released in greater amounts than normal

 A psychoactive drug is a substance that alters perceptions and mood  Dependence can be physical:  Physiological need  Marked by unpleasant withdrawal symptoms  Or dependence can be psychological:  Eg to relieve negative emotions  Tolerance is needing more of the drug to get the same effect

 Depressants  Reduce neural activity  Slow body functions  Alcohol, barbiturates, opiates  Stimulants  Excite neural activity  Speed up body functions  Caffeine, nicotine, amphetamines, cocaine  Hallucinogens  Psychedelic drugs that distort perceptions and cause sensory images (hallucinations) in the absence of sensory input  LSD, marijuana  asp asp

* Affect CNS by increasing heart rate, blood pressure, & muscular tension * Increase attentiveness, less need for sleep and food, can reduce anxiety * Caffeine can improve mood by mimicking brain chemical, adenosine  Eg. amphetamines, ecstasy, nicotine, caffeine and cocaine COCAINE:  Snorted, smoked, or injected  Increases well being, confidence, alertness, decreases appetite  Affects the neurotransmitter “dopamine”: normally, excess dopamine in a synapse is reabsorbed by the releasing axon  Cocaine blocks reabsorption, flooding brain with dopamine  pleasurable sensations  Afterwards, no dopamine is left over, and this produces the “crash” – feeling down, depressed once drug is worn off  Very addictive STIMULANTS

DEPRESSANTS (“downers”)  Reduce anxiety, slow down mental function, neurons fire more slowly  Inhibit brain’s normal functioning  Speech can become slurred, muscle control is reduced  Eg. alcohol, barbiturates, benzodiazepenes  Benzodiazepines enhance the effect of the neurotransmitter gamma- aminobutyric acid, which results in sedative, hypnotic (sleep-inducing), anxiolytic (anti-anxiety), anticonvulsant, muscle relaxant and amnesic action. [2] These properties make benzodiazepines useful in treating anxiety, insomnia, agitation, seizures, muscle spasms, alcohol withdrawal and as a premedication for medical or dental procedures.neurotransmittergamma- aminobutyric acidsedativehypnotic anxiolyticanticonvulsantmuscle relaxantamnesic [2]anxiety insomniaagitationseizuresmuscle spasmsalcohol withdrawal premedication

 Increase relaxation, relieve pain & anxiety  Also have a euphoric effect  Eg. morphine & heroin, oxycodone, codeine

HALLUCINOGENS Psychedelic drugs produce a loss of contact with reality:  Produce changes in perceptions, like:  HALLUCINATIONS -- perceptions that have no direct external cause – seeing, hearing, feeling, etc. things that don’t exist.  Hallucinations can be caused by hypnosis, meds, withdrawal from drugs, psychological breakdowns, prolonged sleep deprivation  Eg. Marijuana – scientific name - Cannabis sativa (Indian hemp)active ingredient THC (tetrahydrocannabinol)  It is usually smoked by various methods, but is also eaten in many various forms – there are also lotions for medicinal uses  Can produce euphoria, well being, but can also produce paranoia and sadness  Makes sensory experiences more intense  Magnifies both + and – feelings  Impairs memory