VIEWS: 27 PAGES: 4 POSTED ON: 4/17/2010
Drug Use, Misuse, Abuse I. Drugs and Effects Drug: a chemical effecting mood and/ or function. Many target the nervous system. (A) Nervous System Overview -1- Central Nervous System (CNS) = Brain and Spinal Cord. Responsible for integration (decision making). -2- Peripheral Nervous System (PNS) divided into sensory/ afferent and motor/ efferent divisions. a. Somatic subdivision controls voluntary muscles. b. Autonomic subdivision controls involuntary muscles and glands. Parasympathetic activity for maintenance and regulation; sympathetic responses for stress. -3- Most communication via neurotransmitters- may be stimulatory or inhibitory. The effect depends upon the receptor type of the receiving cells. Drugs may be neurotransmitter mimetics or blocking agents. Neurotransmitters include epinephrine, norepinephrine- both sympathetic; Acetylcholine (parasympathetic), dopamine, serotonin („feel good‟ chemicals) and many more. (B) Administration Oral, inhaled, injected (subcutaneous, intravenous, intramuscular), topical (creams, patches), sublingual. Dosage crucial, most with toxicity. Responses may be individual. Drugs deactivated in the liver or excreted in urine. II. Medications Listed in the PDR: Physicians Desk Reference. OTC (over-the-counter) regulated by the FDA. Medications may have up to three names: Brand (e.g. Bayer); generic (aspirin): chemical (salicylates). (A) OTC – potentially unsafe. Some converted from prescription, recently gyne-lotrimin/ monistat (vaginal yeast); peptid AC/ tagamet (acid reflux). Most misused are nasal sprays- overuse can have the opposite effect; laxatives; eye drops; sleep aides; cough syrup (ingredient DXM used to make „ecstasy‟). Dependence on these remedies can cause the body to lose its own regulatory abilities. -1- Psychoactive: mind altering. a. stimulants ephedrine (now illegal to sell) caffeine: the most commonly used psychoactive drug. In coffee, teas, sodas, medications (anacin, exedrin, midol). Increases heart rate, respiratory rate, blood pressure, can lead to dependence, anxiety, digestive effects, dizziness. Eventual tolerance to the diuretic effect. Used as a diet aide. Most negative health effects not well documented. b. sedatives Only one currently OTC is scopolamine (in Dramamine). -2- Analgesics, for pain relief. Aspirin, acetaminophen and ibuprofen. All three are also antipyretic (reduce fever), aspirin and ibuprofen are anti-inflammatory, only aspirin is a blood thinner. a. aspirin = salicylates. Quick absorption, irritates stomach, increases bleeding time, inhibits platelets, prevents clots. Risk of Reyes Syndrome in children with viral infections – 25% fatal cases. b. acetaminophen- Tylenol, datril. Overuse causes liver damage. c. ibuprofen- advil, nuprin, motrin. Overuse causes stomach irritation, liver damage. -3- Cold and Allergy- symptom treatment for viral infections. Antihistamines for runny nose, watery eyes, itching; Decongestants for stuffy nose and sinuses (most contain Pseudephedrine). (B) Prescription- new not always better. Problems = nonadherance (antibiotic resistance), physical side effects, allergies, psychological effects, drug interactions. III. Commonly Abused or Recreational Drugs All psychoactive, target the nervous system, many increase levels of dopamine, norepinephrine and GABA. May result in dependence (psychological and/ or physical), tolerance, withdrawal. (A) Amphetamines Increase levels of norepinephrine, epinephrine, dopamine. Increases heart rate, blood pressure, dimishes appetite, causes bronchodilation. Benzedrine (bennies), methamphetamine (crystal meth), speed, Ritalin (treats ADD). Presrcibed for narcolepsy, as diet aides. Dependence, possible withdrawal. (B) Cannabis- Active ingredient = THC. Marijuana, hashish (concentrated resin). Increases appetite, euphoria, some panic, decreases intraocular pressure (treats glaucoma). Consistent effects not well documented. Steady release from fat. Prevents wasting in AIDS and chemotherapy patients. Damages lungs- 50% more tar than tobacco. Some with withdrawal. (C) Cocaine from the South American coca plant. Forms vary- inhaled as powder, dissolved and injected (speedballing when combined with heroin), smoked as crack/ freebase (cheapest). Stimulates CNS, increases dopamine, norepinephrine and serotonin. Brief euphoria, quick dependence. Dangerous with alcohol. Complicates pregnancy, prevents healthy weight gain. Some withdrawal, especially behavioral. (D) Club Drugs MDMA (ecstacy)- stimulant, mildly hallucinogenic; ketamine (Special K); rohypnol (roofies)- odorless, tasteless, mixed in drinks, associated with date rape. Risks similar to cocaine and amphetamines. Loss of behavioral inhibition. (E) Hallucinogens change thoughts, feelings, perceptions. Intense imagry, synesthesia (blending senses, e.g. „seeing sounds‟). LSD- very potent, rapid tolerance. No dependence. Risks associated with sympathetic activity. Mescaline from peyote- similar effects. PCP- associated with manic behavior, violence. Psilocybin mushrooms. (F) Inhalants Gaseous anesthetics (nitrous oxide); solvents, aerosols, glue. May stimulate, intoxicate. Volatile solvents very dangerous; may lead to cardiac arrhythmia, asphyxiation, brain damage (due to oxygen deprivation). (G) Opioids derived from the Asian Poppy plant. Enhance endorphin release- pain relief, euphoria, suppresses coughs, treats diarrhea. Morphine, codeine, heroin. Synthetic nonopioids act similarly = Demerol, methadone, darvon. All addictive, rapid dependence, terrible withdrawal (symptoms like intestinal flu). Methadone maintenance controversial – avoids needle use, facilitates counseling. (H) PCP – Phencyclidine. Angel dust with marijuana. Once used for surgical anesthesia, doesn‟t suppress respiration. Unpredictable effects, associated with violence. (I) Depressants- sedatives, hypnotics. Benzodiazepines = Librium, valium, xanax. Used to treat anxiety. Depress CNS. Replaced barbiturates (anything with name ending “barbital”), very dangerous with alcohol. Risk of apnea. Methaqualone = Quaaludes. Dependence and withdrawal. IV. Alcohol 100 proof = 50% ethanol. Concentration increased with distillation. One drink defined as ½ oz. ethanol. BAC (blood alcohol concentration) legal limit: .08%. More than 3 mixed drinks/ hour/ 150 lb. man. Quickly absorbed, from stomach. Inhibits ADH for diuretic effect. Processed by liver (damaged with abuse), fat deposits, leads to cirrhosis. Excess also damages cardiovascular system, impairs immunity, increases cancer risk, peptic ulcers, drug interactions. Fetal Alcohol Syndrome effects 1/750 babies. Facial defects (droopy eyelids, far- spaced eyes, flat nasal bridge, area between nose and upper lip wide and flat); other organ defects; learning disabilities/ retardation. Tolerance, dependence, withdrawal (potentially fatal due to BP extremes). Delirium Tremens (DTs), increased heart rate, siezures. V. Tobacco Active ingredient = nicotine. Many contaminants contain tars. Highly addictive. Mimics acetylcholine. Stimulates CNS (short puffs) or sedative (long drags). Increases adrenaline, heart rate, blood pressure, diminishes appetite and taste. Causes dermal vasoconstriction. Smoke contains carbon monoxide, decreases blood oxygen transported on hemoglobin. Declared a health hazard in 1964. Many risks: Cardiovascular disease, blood clots, cancers (especially lung), COPD (chronic obstructive pulmonary disease)- chronic bronchitis, asthma & emphysema. Associated with ulcers, gum disease, cirrhosis, osteoporosis. Low infant birth weight, SIDS, increased miscarriage risk. Other forms: cigars, clove cigarettes, bidis, pipes- also significant risks. Smokeless forms = snuff and chewing tobacco also addictive and associated with mouth cancers. Environmental/ second hand smoke defined by EPA as a carcinogen. Similar effects. Most dangerous= side stream smoke from lit cigarettes, not exhaled. Terrible withdrawal. Nicotine replacement therapy with gum, patches.
"Drug Use_ Misuse_ Abuse"