Chapter 25 Outline. Chapter 25: Drug Abuse. Chapter 25 Outline. Drug Abuse. Drug Abuse. Drug Abuse. Drug abuse. Drug abuse

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1 Chapter 25: Drug Abuse Drug abuse Chapter 25 Outline General considerations Definitions Psychologic dependence Physical dependence Tolerance Addiction, habituation, and dependence Central nervous system (CNS) depressants Ethyl alcohol Nitrous oxide Opioid analgesics Sedative-hypnotics 2 Chapter 25 Outline Drug Abuse Drug abuse CNS stimulants Cocaine Amphetamines Caffeine Tobacco Psychedelics (hallucinogens) Lysergic acid diethylamide Phencyclidine Marijuana Identifying the drug abuser Haveles (pp ) Dental health care workers may become involved with drug abuse in a variety of ways They should become familiar with the various types of drugs commonly abused and their patterns of abuse Alcohol and tobacco abuse causes more medical problems than all of the other drugs of abuse combined The impaired dental health care worker 3 4 Drug Abuse Drug Abuse The idea of using drugs to produce profound effects on mood, thought, and feeling is as old as civilization The forms of drugs used today are much stronger and have a much faster onset of action This quick reinforcement produces abuse more quickly Agents used for their psychoactive properties can be divided into those that have therapeutic value and those that have no proven therapeutic value Some agents may move from one category to another Marijuana, previously considered to be worthless, is now claimed to be useful in the treatment of nausea associated with cancer chemotherapy and for glaucoma 5 6 1

2 General Considerations General Considerations Haveles (pp ) Definitions Psychologic dependence Physical dependence Tolerance Addiction, habituation, and dependence Haveles (p. 309) Abuse of a drug is defined as the use of a drug for nonmedical purposes, almost always for altering consciousness Both legitimate and illegitimate drugs may be abused Misuse of a drug means using the drug in the wrong dose or for a longer period than prescribed 7 8 Definitions Definitions Haveles (p. 309) Abstinence syndrome A state of being free of drugs, which is the goal of any treatment program Addiction This vague term should be replaced with dependence The pattern of abuse that includes compulsive use despite complications and frequent relapses after quitting Dependence A combination of either physical or psychologic manifestations occurring in a drug-dependent person when the drug is removed Drug abuse Self-administration of a drug in a socially unacceptable manner, resulting in negative consequences 9 10 Definitions Definitions Drug dependence A state, which may be physical, psychologic, or both, that occurs as a consequence of the interaction between a drug and a patient Characterized by a compulsion to take the drug to obtain its effects or to prevent the abstinence syndrome Enabling The behavior of family or friends that associate with the addict that results in continued drug abuse Habituation Physiologic tolerance to or psychologic dependence on a drug, short of addiction Physical/physiologic dependence The state in which the drug is necessary for continued functioning of certain body processes Psychologic dependence The state in which, after withdrawal of the drug, manifestations of emotional abnormalities and drugseeking behavior occur

3 Definitions Psychologic Dependence Tolerance Haveles (p. 309) With repeated dosing, the dose of a drug must be increased to produce the same effect, or The same dose of a drug produces less effect with consecutive dosing Withdrawal The constellation of symptoms that occurs when a physically dependent person stops taking the drug A state of mind in which a person believes that he or she is unable to maintain optimal performance without having taken the drug Although some highly abused drugs have only psychologic dependence, the need to use these drugs can be as strong or stronger than drugs with a physical dependence Physical Dependence Tolerance Haveles (p. 309) The altered physiologic state that results from constantly increasing drug concentrations The presence of physical dependence is established by the withdrawal or abstinence syndrome Withdrawal symptoms are often the opposite of the symptoms of use of the drug Haveles (p. 309) Characterized by the need to increase the dose continually to achieve the desired effect or the giving of the same dose, which produces a diminishing effect Central tolerance is a definite decrease in the response of brain tissue to constantly increasing amounts of the drug Addiction, Habituation, and Dependence Addiction, Habituation, and Dependence Haveles (pp ) The desire to continue using the drug is present in both addiction and habituation, but dependence is also present in addiction Habituation and dependence are really only degrees of misuse or abuse of drugs Experts recommend that these terms be replaced by dependence, a state of psychologic or physical desire to use a drug Haveles (pp ) Drugs that produce tolerance and physical dependence are grouped according to their ability to be substituted for one another The phenomenon of substitution to suppress withdrawal between different drugs is called crosstolerance or cross-dependence

4 Addiction, Habituation, and Dependence Approximately 80% of incarcerated individuals are there because of drug abuse problems Problems and treatment are less related to the drugs themselves than to the inner person of the patient involved in this type of behavior and his or her genetic predisposition Addiction, Habituation, and Dependence Haveles (p. 310) Abusable drugs are divided into CNS depressants CNS stimulants Hallucinogens Some drugs may fall in more than one group Central Nervous System Depressants Ethyl Alcohol Haveles (pp ) Include alcohol, opioids, barbiturates, benzodiazepines, volatile solvents, and nitrous oxide Haveles (pp ) The most often abused drug Alcoholism is the number one public health problem in the United States The incidence of alcoholism in the United States is about 10% Pharmacokinetics of Ethyl Alcohol Acute Intoxication of Ethyl Alcohol Haveles (p. 310) (Fig. 25-1) Ethyl alcohol is rapidly and completely absorbed from the gastrointestinal tract Peak levels while fasting occur in less than 40 minutes Food delays absorption and reduces the peak levels Metabolism follows zero-order kinetics; thus a constant amount is metabolized per unit of time, regardless of the amount ingested Haveles (p. 310) Impairment of judgment, emotional lability, and nystagmus occur with mild intoxication Dilated pupils, slurred speech, ataxia, and a staggering gait are noted with moderate intoxication Seizures, coma, and death can occur if intoxication is severe Treatment includes fluids and electrolytes, thiamine (vitamin B 6 ), sodium bicarbonate, and magnesium

5 Withdrawal from Ethyl Alcohol Withdrawal from Ethyl Alcohol Haveles (pp ) Stage 1 usually begins 6 to 8 hours after drinking has stopped and includes withdrawal, psychomotor agitation, and autonomic nervous system hyperactivity Stage 2 withdrawal includes hallucinations, paranoid behavior, and amnesia Stage 3 includes disorientation, delusions, and grand mal seizures A cross-tolerant benzodiazepine may be used to prevent withdrawal symptoms Withdrawal is termed delirium tremens (DTs) because the patient will often experience shaky movements Chronic Effects of Ethyl Alcohol Alcoholism Haveles (p. 311) Chronic medical effects include deficiency of proteins, minerals, and water-soluble vitamins Fetal alcohol syndrome can occur if a pregnant woman is using ethanol chronically More severe cases include cardiac abnormalities and mental retardation Chronic alcohol use increases the risk of cancer of the mouth, pharynx, larynx, esophagus, and liver Haveles (pp ) (Box 25-1) A disease in which the alcoholic continues to drink despite the knowledge that drinking is producing a variety of problems A genetic link for alcoholism exists Red flags include drinking at an inappropriately early time, shaking when not drinking, blackouts when drinking, and being told that you drink too much Treatment of Alcoholism Treatment of Alcoholism Haveles (p. 312) Alcoholics anonymous Haveles (p. 312) Drug treatment A self-help organization made up of recovering alcoholics Members give support to alcoholics who are attempting recovery Outpatient psychiatric treatment can help provide some insight for alcoholics Alcoholics who are motivated and socially stable can be given disulfiram A buildup of acetaldehyde occurs because disulfiram inhibits the metabolism of aldehyde dehydrogenase Acetaldehyde produces significant side effects if alcohol is ingested These effects include vasodilation, flushing, tachycardia, dyspnea, throbbing headache, vomiting, and thirst

6 Treatment of Alcoholism Naltrexone was originally used to prevent relapse in the opioid-dependent patient Its new use is to reduce alcohol craving More detailed knowledge of the receptors affected by alcohol may increase the chance of developing other agents to manage this disease Dental Treatment of the Alcoholic Patient Haveles (pp ) (Fig. 25-3) Dental treatment of the alcoholic patient includes some modifications Most alcoholic patients have poor oral hygiene Check for sweet musty breath and painless bilateral hypertrophy of parotid glands Cirrhosis of the liver can occur when alcoholics continue to abuse alcohol Dental Treatment of the Alcoholic Patient The liver is able to store less vitamin K, and conversion of vitamin K to the coagulation factors is reduced because of hepatic failure The outcome of these effects is a deficiency in coagulation factors II, VII, IX, and X, with resulting bleeding tendencies The patient s international normalized ratio (INR) can be elevated Thrombocytopenia secondary to portal hypertension and bone marrow depression magnifies the hemostatic deficiency Spontaneous bleeding can occur due to the presence of esophageal varices Dental Treatment of the Alcoholic Patient Haveles (p. 313) (Box 25-2; Table 25-2) Oral complications include glossitis, loss of tongue papillae, angular/labial cheilosis, and Candida infection The dental health care worker should check any oral lesions carefully because alcohol and tobacco use and abuse predispose a patient to oral squamous cell carcinoma Dose reductions may be necessary because of diminished liver function Nitrous Oxide Abuse Pattern of Nitrous Oxide Haveles (p. 314) Haveles (p. 314) (Fig. 25-4) Abuse can result in psychologic but not physical dependence Inhalation of 50% to 75% produces a high for 30 seconds followed by a sense of euphoria and detachment for 2 to 3 minutes Tingling or warmth around the face, auditory illusions, slurred speech, and a stumbling gait can occur Nitrous oxide is an incomplete general anesthetic readily available in many dental offices It is abused primarily by dentists, dental hygienists, and dental assistants

7 Adverse Reactions of Nitrous Oxide Adverse Reactions of Nitrous Oxide Haveles (p. 314) General Adverse reactions include dizziness, headache, tachycardia, syncope, and hypotension Nitrous oxide impairs the ability to drive or operate heavy machinery Can produce chronic mental dysfunction and infertility with chronic use Haveles (p. 314) Myeloneuropathy Chronic use or abuse of nitrous oxide can lead to myelopathy, resulting in a combination of symptoms pathognomonic for nitrous oxide abuse Initial symptoms include loss of finger dexterity and numbness or paresthesia of the extremities Later, Lhermitte sign, clumsiness, and weakness can be demonstrated Neurologic deficiencies include extensor plantar reflex and polyneuropathy The neurologic deficiency is similar to that of spinal cord degeneration in pernicious anemia Opioid Analgesics Pattern of Abuse Haveles (pp ) Heroin, methadone, morphine, hydromorphone, meperidine, oxycodone, and oxycodone sustained release are currently the most popular abused opioids In addition to being analgesics, opioids produce a state described as complete satiation of all drives in some people The driving motivation to obtain the drug becomes more and more negative with the development of physical dependence Haveles (p. 314) Heroin is the most commonly administered parenteral opioid The signs and symptoms of an acute overdose are fixed, pinpoint pupils, depressed respiration, hypotension and shock, slow or absent reflexes, and drowsiness or coma Tolerance develops to most of the pharmacologic effects but does not develop to miosis or constipation Pattern of Abuse Management of Acute Overdose and Withdrawal The symptoms and time course of the withdrawal syndrome are determined by the specific drug abused and the dose of the drug The first signs of withdrawal from heroin are yawning, lacrimation, rhinorrhea, and diaphoresis, followed by a restless sleep Anorexia, tremors, irritability, weakness, and excessive gastrointestinal activity occur with further abstinence Haveles (pp ) Naloxone should be administered immediately if the triad of narcotic overdose (respiratory depression, pinpoint pupils, and coma) is present Patients in withdrawal can be made comfortable with methadone, a long-acting opioid that can replace heroin and then be gradually withdrawn

8 Dental Implications Dental Implications Haveles (p. 315) Pain control Because an opioid abuser develops tolerance to the analgesic effects of any opioid, treating patients with opioids is ineffective and can cause a recovering addict to begin using opioids again Best to alleviate the cause of the pain and then prescribe nonsteroidal antiinflammatory drugs Haveles (p. 315) Prescriptions for opioids Abusers often come to the dental office requesting an opioid for severe pain Increased incidence of disease Certain diseases that can be transmitted by the use of needles for injections have a higher incidence in opioid abusers Chronic pain Patients who have pain for a much longer time than normal deserve a workup for chronic pain Opioid Street Drugs Sedative-Hypnotics Haveles (p. 315) Haveles (pp ) Opioids available on the street change with time and are different in different parts of the country The dental health care worker should be aware that most drug abusers misuse more than one substance and that street drugs are often adulterated Sedative-hypnotics include barbiturates, alcohol, meprobamate, methaqualone, chloral hydrate, benzodiazepines, and nitrous oxide Initial symptoms resemble the well-known symptoms of alcohol intoxication Drowsiness and sleep occur with increasing doses, respiration is depressed, cardiac output is decreased, and gastrointestinal activity and urine output is diminished Pattern of Abuse of Sedative- Hypnotics Pattern of Abuse of Sedative- Hypnotics Haveles (pp ) CNS depressant drugs are generally taken orally Respiratory and cardiovascular depression occur with an acute overdose, leading to coma and hypotension The pupils may be unchanged or small, and lateral nystagmus is seen Confusion, slurred speech, and ataxia are always present Haveles (pp ) The first signs of withdrawal are insomnia, weakness, tremulousness, restlessness, and perspiration Delirium and convulsions may culminate in cardiovascular collapse and loss of the temperature-regulating mechanism Another troubling abuse of sedative-hypnotics involves administering them to other people to control them

9 Management of Acute Overdose and Withdrawal of Sedative-Hypnotics Haveles (p. 316) The most important consideration with an acute overdose of a CNS depressant is support of the cardiovascular and respiratory systems Withdrawal from CNS depressants can be life threatening, and the patient should be hospitalized A long-acting benzodiazepine is usually substituted for the abused drug and then gradually withdrawn over a period Central Nervous System Stimulants Haveles (pp ) Cocaine Amphetamines Caffeine Tobacco Cocaine Amphetamines Haveles (p. 316) Cocaine is a CNS stimulant with local anesthetic properties when applied topically Cocaine induces intense euphoria, a sense of total self-confidence, and anorexia Paranoia and extreme excitability cause some cocaine users to perform violent acts while under its influence Psychologic dependence becomes intense, but neither tolerance nor withdrawal has been shown Haveles (p. 316) Pattern of abuse Sympathomimetic CNS stimulants are abused for their ability to produce a euphoric mood, a sense of increased energy and alertness, and a feeling of omnipotence and self-confidence With prolonged use, tolerance to the euphorigenic effect develops, and toxic symptoms appear Signs and symptoms of an acute overdose include dilated pupils, elevated blood pressure, rapid pulse, and cardiac arrhythmias Amphetamines Caffeine Haveles (p. 316) Management of acute overdose and withdrawal Treatment of an overdose of a CNS stimulant is symptomatic The most serious sociologic problem with stimulant abuse is the induction of mental abnormalities Experimental evidence suggests that amphetamine psychoses can be induced in previously unaffected volunteer subjects Haveles (p. 317) (Table 25-3) Caffeine stimulates the CNS Toxicity can occur with as little as 300 mg of caffeine contained in two or three cups of coffee A withdrawal syndrome can be identified that begins around 24 hours after the last cup of coffee Symptoms consists of headache, lethargy, irritability, and anxiety

10 Tobacco Tobacco Haveles (pp ) Nicotine Haveles (p. 317) Pattern of Abuse The CNS active component of tobacco is nicotine A large number of components of the gaseous phase of tobacco smoke contributes to its undesirable effects These components include carbon monoxide, nitrogen oxides, volatile nitrosamines, hydrogen cyanide, volatile hydrocarbons, and many other substances Approximately 25% of the adult American population smokes Children commonly begin smoking between 11 and 14 years of age Chronic use of tobacco is causally related to many serious diseases, including coronary artery disease and oral and lung cancers Tobacco Tobacco Haveles (p. 317) Smokeless tobacco More than one quarter of high school boys use chewing tobacco in some communities Oral mucosal changes include chronic gingivitis, leukoplakia, and precancerous lesions Haveles (p. 317) (Table 25-4) Management and withdrawal The withdrawal syndrome that occurs after cessation of chronic tobacco smoking varies greatly from person to person The most consistent symptoms are anxiety, irritability, difficulty in concentrating, and cravings for cigarettes The syndrome of withdrawal from tobacco can be suppressed to some extent by administration of nicotine chewing gum or nicotine patches Tobacco Tobacco Haveles (p. 317) Bupropion Another approach to treating tobacco cessation involves the use of bupropion, an antidepressant, to reduce craving Varenicline Varenicline is a nicotine-receptor blocker that binds to the nicotine receptor and prevents the nicotine from tobacco from reaching its receptor site By binding to the receptor, varenicline limits the amount of dopamine that is released in the brain The most common side effects include nausea, sleep problems, constipation, gas, vomiting, and changes in mood and behavior

11 Tobacco Psychedelics (Hallucinogens) Lysergic acid diethylamide (LSD) Phencyclidine (PCP) Marijuana The dental health care worker s role in tobacco cessation Dental health care workers are in a special situation to be helpful in promoting tobacco cessation because of their role in encouraging patients to change habits Smoking cessation is another habit change Psychedelics Lysergic Acid Diethylamide Psychedelic agents are capable of inducing states of altered perception and generally do not have any medically acceptable therapeutic use Psychedelics affect perception in such a way that all sensory input is perceived with heightened awareness Psychedelic-induced dependence is psychologic, and tolerance develops within a short time LSD is the most potent hallucinogen An overdose of LSD produces symptoms that include widely dilated pupils, flushed face, elevated blood pressure, visual and temporal distortions, hallucinations, derealization, panic reactions, and paranoia Flashbacks can occur years after ingesting LSD Phencyclidine Marijuana The effects of marijuana include an increase in pulse rate, reddening of the conjunctivae, and behavioral changes Euphoria and enhanced sensory perception occur with normal doses This phase is followed by sedation and altered consciousness Psychologic dependence is determined by the frequency of use Physical dependence, tolerance, and withdrawal symptoms are rare PCP, originally developed as an animal tranquilizer, was popular in the 1970s PCP inhibits the reuptake of dopamine, serotonin, and norepinephrine PCP is a powerful CNS stimulant with dissociative properties Changes in body image and disorganized thought have led to bizarre behavior and psychosis

12 Identifying the Drug Abuser Impaired Dental Health Care Worker A professional who is abusing drugs is in denial, and confrontation by staff, relatives, and friends is often ineffective The dentist s practice deteriorates, and mood swings occur Any dental health care worker who observes or suspects that another worker is abusing drugs should report the person to the appropriate impaired professional committee Shoppers interact with many health care workers in an attempt to obtain controlled substances for illegitimate uses Many shoppers are excellent storytellers and actors with convincing histories and the presence of a pathologic dental condition They may suggest certain drugs or give a history of allergy to analgesics they do not want