Transcript Uppers Downers & All Arounders
Uppers Downers & All Arounders
Chapter 2, Part II
Physiological Responses to Drugs
• Determines how drugs affect people and why it is difficult to control their levels of use.
• They include: – Tolerance to Drug – Tissue Dependence – Psychological Dependence & Reward reinforcing action of drugs – Withdrawal
Tolerance
• Results from the body’s attempt to eliminate a drug that it treats as a toxin • With continued drug use the body tries to neutralize the toxic effects by: – Requiring larger amounts of the drugs to achieve the original effects • Degree of effects depend on the : – Amount used – Duration of use – Frequency of use – Individual’s chemistry – State of mind
Kinds of Tolerance
• Dispositional Tolerance – Speeds up the metabolism to handle the drug in order to eliminate it – Example: Increases the amount of cytocells and mitochondria in the liver to neutralize the drug….. So it will take more of the drug to achieve the same level of intoxication
Kinds of Tolerance
• Pharmacodynamic Tolerance – Results from the desensitization of nerve cells to the action of the drug – Ex. The nerve cells become less sensitive and begin producing an antidote or antagonist to the drug, ie. The brain will generate more opiod receptor sites.
Kinds of Tolerance
• Behavioral Tolerance: – Brain adjustments that affect behavior – Someone who is high may make himself appear sober when threatened, then revert back to the high state • Reverse Tolerance – Person has greater sensitivity to the drug, after prolong use, and the body’s ability to metabolize the drug decreases. – Ex. A person who has drunk a 12-pack of beer daily for ten years, may find themselves drinking 3-4 beers to achieve the effect due to tissue damage of the liver and kidneys.
– Also, the person may stay drunk longer as the liver is no longer metabolizing the alcohol and the alcohol just continues to circulate in the body until it is eliminated.
Kinds of Tolerance
• Acute Tolerance: – The body’s immediate resistance to the effects of the drug – Ex. The brain and the body adapts instantly to the drug, as with tobacco • Select Tolerance: – The body will develop a tolerance to some effects of the drug, but not to other effects resulting in potentially fatal side-effects in high doses of the drug.
– Ex: The body may not feel the euphoric effect, but the organs of the body may react adversely to the drug: respiratory function of the lungs and continue damage to the liver
Kinds of Tolerance
• Inverse Tolerance (Kindling) – Person becomes more sensitive to the drug as the brain chemistry changes – After months of using marijuana or cocaine with minimal effect, the drug user may get an intense effect/reaction – Greater risk for heart attack or stroke
Development of Amphetamine Tolerance Over Time Desired effect
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• Tolerance develops rapidly to amphetamines. As the body adapts to the toxin, the liver, brain, and other tissues become better able to handle greater amounts. One dose of amphetamine on day 1 can increase to 30 doses on day 100 to achieve the same effect. Tolerance usually develops with higher-dose chronic use. Low-dose infrequent use induces only minimal tolerance. (p.58)
Tissue Dependence
• Biological adaptation of the body to the drug such that the body comes to depend on the drug to stay in balance.
• The tissues and organs of the body come to depend on the drug to stay functional – Ex. Alcoholic will need a drink to ward off the shakes – Heroin addict will need a fix to stop body aches, headaches
Psychological Dependence & the Reward-reinforcing Action of the Drugs • Results from the action of the drugs on the brain chemistry • Pleasurable effects induce user to continual use • Recognized as an important factor that contributes to addiction • Altered states of distorted perceptions of pleasurable feelings prompt users to avoid life’s problems
Withdrawal
• Marked by unpleasant effects that follow the cessation of drug use as the body attempts to restore its chemical balance – Withdrawal can be so severe that the user will continue to use drugs to avoid withdrawal symptoms • Kinds of Withdrawal – Non-purposive Withdrawal – Purposive – Protracted Withdrawal
Kinds of Withdrawal
• Non-purposive: – Series of unpleasant or even life-threatening physiological effects that accompanies cessation of use by an addict – Example: Sweating, headaches, vomitting, diarrhea, body aches, tremors, • Purposive: – Emotional expectation of physical effects – Manipulative counterfeiting in an effort to obtain more drugs, money or sympathy
Kinds of Withdrawal
• Protracted withdrawal (environmental triggers and cues) – Flashback or recurrence of addiction withdrawal symptoms that trigger heavy craving for a drug long after detoxification – Cravings can be triggered by a sensation associated with prior use and can be strong enough to cause relapse – PAWS (Post Acute Withdrawal Syndrome)
OPIOD EFFECTS VS WITHDRAWAL SYMPTOMS Numbness EFFECTS Euphoria Dryness of mouth Constipation Slow pulse Low blood pressure Shallow breathing , Suppressed cough Pinpoint pupils Sluggishness Withdrawal Symptoms Becomes painful Anxiety, depression or craving Sweating, runny nose, tearing, increased salivation Diarrhea Rapid pulse High blood pressure Coughing Dilated pupils Severe hyper-reflexes, muscle cramps
Basic Pharmacology
• Metabolism & Excretion – Metabolism is the ability of the body to process, use and inactivate drugs or food – Chief organ of metabolism is the liver – Metabolism rates vary depending on the age, gender, race, heredity, general health, emotional state, presence of other drugs, weight, tolerance and exaggerated or allergic reactions – Excretion is the process of elimination of those substances from the body – Chief organs of excretion are the kidneys via the Urethra • Other pathways of excretion is the sweat glands, & lungs
The liver is most responsible for metabolizing, detoxi-fying, and eliminating drugs. The drug laden blood enters through the portal vein, is processed by various enzymes, and then sent via the hepatic vein to the heart where it is then pumped to the rest of the body. If the alcohol and another depressant drug are taken together, they compete for the same enzymes so the liver allows the other to enter the circulatory system at full strength.
The Liver
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Desired Effects vs Side Effects
• Desired Effects include: – Satisfying curiosity, getting high, self-medicating, gaining self confidence, increased energy, relieving pain, controlling anxiety, peer pressure, social confidence, boredom, altering consciousness, coping with isolation, competion, seeking oblivion • Side Effects: (Biopsychosocial) – Mild to moderate to fatal effects • Polydrug Use: – Combination of more than one drug – May use another drug to replace the unavailable one – Get a different feeling – Enhance effects – Counteract effects – Cross addiction
LEVELS OF USE Copyright, 2004, CNS Productions, Inc.
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LEVELS OF USE • Abstinence: – Not using drugs, except accidentally – With true abstinence, drug craving cannot develop not matter how high hereditary and environmental predisposition factors are • Experimentation: – Infrequent use of a drug to satisfy curiosity – Only few exposures, no pattern of use develops – Problematic consequences can occur if user is pregnant, driving, has physical or mental illness, has an alergic reaction or has legal problems
LEVELS OF USE • Social/recreational Use – Use has irregular pattern with small impact on person’s life – Same consequences of use can occur as with experimentation • Habituation: – Regular pattern of use and loss of some control over a drug with minimal harmful consequences • Drug Abuse – Continues to use despite negative consequences, including health, school, work, emotional well-being and drug use continues on a regular basis.
LEVELS OF USE • Addiction/Dependency – Difference between abuse and Addiction is the Compulsion to use – Uses drug in larger amounts or for longer periods of time – Unsuccessfully tries to cut down or control use – Spends a great amount of time in activities to obtain drugs or recover from use – Gives up or reduces important social, occupational or recreational activities because of use – Continues use despite knowledge that drug use is causing physical or psychological problems
Theories of Addiction • DSM IV-TR divides substance related disorders into substance use and substance induced disorders • Substance use disorders are divided into abuse and dependency • Substance-induced disorders include conditions that are caused by specific substances, intoxication, withdrawal, delirium, etc.
• Theories of Addiction focus on the environment, the host (user) and agent (drug itself) and the interactions between them
Theories of Addiction • The Disease Model AKA Medical Model – Addiction is a chronic, progressive, relapsing, incurable and potentially fatal disease – Triggered by drug use that reacts to biochemical and neurological irregularities.
– Sees heredity as more important than environmental influences in moving a person to addiction – Addiction is characterized by impulsive use, loss of control, repeated attempts at abstinence, continuation of use despite negative consequences, and complications resulting from abuse
Theories of Addiction • The Behavioral/Environmental Model – Sees addiction as environmental and developmental influences as the main causes leading a person to addiction.
– Stress, anger and peer pressure are some stress factors • Academic Model – Sees addiction as occurring when body adapts to the toxic effects of drugs.
– Given enough drugs over time, a person will become addicted – The process is characterized by tissue dependence, withdrawal syndrome, and psychic dependence
Theories of Addiction • Diathesis-Stress Theory of Addiction – Result of genetic and environmental factors such as stress – People with a pre-disposition or vulnerability to develop drug addiction is caused by: • genetic and environment factors combined with an • availability of drugs and • practice of certain behaviors.
– When a person is stressed or challenged by the use of drugs or behaviors, then the brain changes to the point where return to normal use or behavior is difficult
Heredity, Environment & Use of Psychoactive Drugs
• Heredity: – Many traits are passed on through generations – Heredity susceptibility to avoid, use or abuse drugs varies from person to person, depending on the brain structure and neurochemical composition – Twin Studies – 34% with one parent, 400% 2 parents, 900% with grandparents – Alcoholic-Associated Genes • DRD A1 Allele gene found in 70% of chronic alcoholics • DRD4 gene with excessive dopamine prevents dependence from developing
Heredity, Environment & Use of Psychoactive Drugs
• Environmental factors include: – Physical/sexual/emotional abuse – Stress – Nutrition – Living conditions – Family relationships – Health care – School quality – Peer pressure – Economic factor
Heredity, Environment & Use of Psychoactive Drugs
• Psychoactive Drugs – Move people further along the compulsion curve • Depends on strength of drug • Amount • Frequency and • Duration of use – Long Term or heavy use may take a person with low susceptibility 10 years of heavy drinking to become an alcoholic – A person with high susceptibility can take just 1 year to become an alcoholic
SPECT stands for single photon emission computerized tomography, a method for imaging the activity of the brain. It shows areas of activity and inactivity. The “holes” in the brain are actually areas that are inactivated by the use of a drug or the practice of some behavior. Abstinence will restore much but not all of the brain function. The more chronic the use, the less restoration of activity. Methamphetamine is more toxic than heroin or cocaine.
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Alcohol is a protoplasmic poison, so much of the inactivation in the brain of a chronic alcoholic can be long lasting. Heroin is less toxic to brain cells, so abstinence will restore more brain function Copyright, 2004, CNS Productions, Inc.
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