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Chapter 17: Pharmacology, Drugs and Sports. Pharmacology is the branch of science that deals with the action of drugs on the biological systems Specifically those that are used in medicine for diagnostic and therapeutic purposes Used to achieve definite outcomes that improve quality of life
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Pharmacology is the branch of science that deals with the action of drugs on the biological systems • Specifically those that are used in medicine for diagnostic and therapeutic purposes • Used to achieve definite outcomes that improve quality of life • Various drugs and other substances are being used widely for performance enhancement or mood alteration
What is a drug? • Chemical agent used in prevention, treatment, & diagnosis of disease • Ancient practice dating back to the Egyptians • Many are derived from natural sources • Drugs which have, in the past, come from nature are now produced synthetically
Pharmacokinetics • Method by which drugs are absorbed, distributed, metabolized and eliminated from the body • Pharmacodynamics is the actions or effects of drugs on the body
Administration of Drugs • Must first enter the system and reach receptor tissue to be effective • Drug vehicles • Therapeutically inactive substance used to transport drug (solid or liquid) • Internal administration • Inhalation (medication through respiratory tract) • Intradermal (into the skin) • Intramuscular (medication directly into muscle) • Intranasal • Intraspinal (medication injected into the spine)
Intravenous (into a vein) • Oral (most common form) • Rectal (limited due to dosage regulation) • Sublingual/buccal (dissolvable agents placed under tongue • Intravaginal (placing drug device inside vagina) • External Administration • Inunctions (oil based medication rubbed into skin) • Ointments (long lasting topical medication) • Pastes (ointments with nonfat base) • Plasters (thick ointment, counterirritant for pain & inflammation relief, increasing circulation) • Transdermal patches (patch with slow release mechanism) • Solutions (administered externally)
Absorption of Drugs • Drug must dissolve before absorption • Rate and extent determined by chemical characteristics of drug, dosage, and gastric emptying • Bioavailability • How completely a drug is absorbed by the system • Dependent on characteristics not dosage • (Absorption rate dependent on dosage form)
Distribution • Once absorbed, drug is transported through blood to target tissue • Volume of distribution: volume of fluid/plasma in which drug is dissolved and indicates extent of distribution of that drug • Efficacy: capability of producing therapeutic effect • Potency: dose of the drug required to produce a desired therapeutic effect • Metabolism • Biotransformation of drug to water soluble compounds that can be excreted • Most takes place in liver, rest in blood and kidneys • Liver detoxifies active agents • Metabolites may be toxic
Excretion • Excretion of drug or its metabolites is controlled by kidneys • Filtered through kidneys and usually excreted in the urine (some is reabsorbed) • May also be excreted in saliva, sweat and feces
Drug Half-Life • The amount of time required for the plasma drug level to be reduced by one half • It is either measured in minutes, hours, or days depending on the drug • Critical information in determining how much of what drug to utilize • Drug steady state • The amount taken is equal to the amount excreted • Drugs with long half-lives may take days or weeks to reach steady state
Effects of Physical Activity on Pharmokinetics • Exercise decreases the absorption after oral administration • Exercise increases absorption after intramuscular or subcutaneous administration due to the increased rate of blood flow • Exercise has an influence on the amount of a drug that reaches the receptor site
Legal Concerns in Administering Versus Dispensing Drugs • Defined as a single dose of medication to be used by a patient • Dispensing constitutes providing a sufficient quantity to be used for multiple doses • By law, only licensed persons may prescribe or dispense prescription drugs for an athlete • ATC’s are not allowed to dispense medication unless allowed by state licensure
Administering Over the Counter Drugs • ATC may be allowed to administer a single dose of nonprescription medication • Rules relative to secondary schools • Oral medications vs. wound medication • College and professional athletes • Most are of legal age and are allowed to use whatever nonprescription drugs they choose • ATC must still use reasonable care and be prudent about types of medication provided • In all cases, actions should be performed under the supervision of a physician
Record Keeping • Must maintain accurate and up to date medical records • Should include the following in log • quantity of medication given • method of administration • Should be aware of state regulations relative to ordering, prescribing, distributing, storing and dispensing of the medications • Obtaining legal counsel, working w/ state boards of pharmacy, student health clinic, physicians and establishing policies to minimize violating state laws
Name Complaint Current medications Any known drug allergies Name of medication Lot number Expiration Date Quantity of medication given Method of administration Date and time of administration Record Keeping-ATC’s must maintain accurate and up to date medical records
Name of product Name and address of manufacturer, packer or distributor Net contents of package Name of active ingredients and quantity of certain other ingredients Name of any habit forming drug contained Cautions and warnings to protect consumer Adequate directions for safe, effective use Expiration date and lot number Labeling Requirements (federally mandated)
Nonprescription drugs should not be repackaged w/out meeting labeling criteria • All drugs dispensed from the athletic training room must be properly labeled • Legal liability if drugs removed from original packaging and dispensed • Unable to review contents, dosage, directions and precautions (information needed for safe use) • Same liability associated with providing prescription medication
Safety in Use of Pharmaceuticals • No drug is completely safe and harmless • Any drug under the correct conditions can be potent and dangerous, w/ every individual reacting differently • Athlete must be instructed on specifics of medications (when to, how to and w/ what medication should be taken with) • Drug Responses • Individuals react differently to the same medications, w/ different conditions causing altered effects of drugs • Drugs can change with aging and relative to how they are administered • Alcohol ingestion w/ medications should be avoided
Alcohol is a CNS depressant and can increase or decrease effects of other drugs • Also used in many liquid preparations • Medication can potentially effect certain physiologic functions related to dehydration (sweating, urination, and the ability to control and regulate body temperature) • Can cause fluid depletion, further complicating illness, or make individuals sensitive to sunlight increasing risk of sunburn and allergic reactions • Different diets may impact absorption rate • Consumption of acidic foods such as fruit, carbonated drinks and vegetable juice may cause adverse reactions • ATC must know their athlete’s in order to avoid potential adverse reactions
Buying Medication • Pharmacist is a vital resource, assisting in selection and purchase of nonprescription drugs, suggesting less expensive generic drugs, and acting as a general advisor • Properly storing medication is critical • Keep in locked cabinet • Maintain original container • Store away from direct light, heat, damp places and extreme cold
Traveling with Medications • When traveling with a team or individually the athlete should be advised to do the following relative to medications • Medication should not be stored in a bag/luggage but carried by the athlete taking it • Sufficient supply should be packaged in case of emergency • Make sure there is a source of medication while traveling • Take copies of written prescriptions • Keep medication in original container • If traveling internationally, understand restrictions of individual boundaries
Selected Therapeutic Drugs to Treat the Athlete • Widespread use in athletics and general society • Pharmaceutical labs develop compounds in vitro and then test, retest, and refine drugs in vivo before submitting it to the Food and Drug Administration (FDA) • Number of texts and databases are available for reference to determine appropriateness and effectiveness of medications for different conditions
Drugs to Combat Infection • Local Antiseptics and Disinfectants • Antiseptics are substances that can be placed on living tissue for killing bacteria or inhibiting growth • Disinfectants are used to combat microorganisms but should be applied to non-living objects • Germicides (generic name) designed to destroy bacteria, fungicides, sporicides and sanitizers
Alcohol • Most widely used skin disinfectant • Ethyl alcohol (70% by weight) and isopropyl alcohol (70% by weight) are equally effective • Inexpensive and nonirritating, kill bacteria immediately with the exception of spores • No long lasting germicidal action, can be used as an antiseptic or astringent • 70% solution can be used to disinfect instruments • Also can be utilized as mild anesthetic and topical skin dressing when combined with 20% benzoin • Phenol • Early antiseptic and disinfectant in medical profession • Used to control disease organisms • Found in various concentrations and emollients • Derivatives include, resorcinol, thymol, and common house cleaner Lysol
Halogens • Chlorine, bromine, fluoride (used for antiseptic effect) • Iodophor or halogenated compounds create a much less irritating solution than tincture of iodine • Betadine solution- excellent germicide, very effective for skin lesions, abrasions and lacerations • Oxidizing agent • Hydrogen peroxide is commonly used in the athletic training room • Readily decomposes in presence of organic substances and has little use as an antiseptic • Cleanses infected cutaneous and mucous membranes • Dilute solution can be used to treat inflammatory mouth and throat conditions
Antifungal Agents • Medicine used to treat fungi (epidermophyton, trichophyton, and candida albicans) • Numerous antifungal agents • Some can be used against deep seated fungal infections • Others are administered orally • Must be carefully monitored by physician • Antibiotics • Chemical agents that are produced by microorganisms • Interferes w/ necessary metabolic processes of pathogenic microorganisms
Used topically or as systemic medication • Indiscriminate use can produce hypersensitivity and prevent development of natural immunity or resistance to subsequent infections • Must be carefully controlled by physician • A number of antibiotics are available • Penicillin • Most important antibiotic • Useful in skin and systemic infections • Interferes w/ metabolism of bacteria • Bacitracin • Antibacterial agent • Tetracycline • Wide group of antibiotics that have broad antibacterial spectrum • Usually oral, modifies infection rather than eradicating it completely
Erythromycin • Used for streptococcal infection and mycoplasma pneumoniae • Same general spectrum as penicillin but can be used with individuals allergic to penicillin • Sulfonamides • Group of synthetic antibiotics • Make pathogens vulnerable to phagocytes and certain enzymatic actions • Quinolones • New group of antibiotics with broad spectrum of activity • Must be carefully monitored for adverse effects
Drugs for Asthma • Used to treat chronic inflammatory lung disorder • National Asthma Education and Prevention Program has established guidelines for diagnosis and treatment • Goals of asthma therapy are to prevent chronic and troublesome symptoms, maintain normal lung function, prevent exacerbation and provide adequate pharmacotherapy with minimal adverse effects • Portable hand-held inhalers are available • Meter dosed inhalers (pressurized canister) • Dry powder inhalers • Nebulizer • Often individuals become dependent on inhalers • Treatment should not just be drug based
Drugs that Inhibit Pain and Inflammation • Pain Relievers • Numerous drugs and procedures can be used • Reasons for effectiveness • Excitatory effect on an individual impulse is depressed • Individual impulse is inhibited • Perceived impulse is decreased • Anxiety created by pain or impending pain is decreased
Counterirritants and Local Anesthetics • Analgesics give relief by causing systemic and topical analgesia • Application causes local increases in circulation, redness, rise in skin temperature • Mild pain can often be reduced w/ counterirritants • Examples include • Liniments • Analgesic balms • Spray coolants • Alcohol • Menthol • Cold • Local anesthetics (injected by physician)
Narcotic Analgesics • Most derived from opium or are synthetic opiates (morphine and codeine) • Depress pain impulse and respiratory center • Examples include • Codeine (morphine like action, found in cough suppressants) • Morphine (dangerous due to respiratory effects, habit forming qualities) • Propoxyphene hydrochloride (slightly stronger than aspirin and can be fatal if mixed with sedatives or depressants) • Meperidine (Demerol - substitute for morphine, effective when given intravenously or intramuscularly)
Non-narcotic Analgesics and Antipyretics • Designed to suppress all but most serious pain w/out losing consciousness • Acetaminophen • Tylenol - effective analgesic and antipyretic but has no anti-inflammatory activity • Does not irritate GI system and is often replacement for aspirin in non-inflammatory conditions • Over-ingestion can lead to liver damage
Drugs to Reduce Inflammation • Acetylsalicylic Acid (Aspirin) • Widely used analgesic, anti-inflammatory, antipyretic and abused drug • Helps reduce pain, fever and inflammation • Adverse reactions generally GI related • Over-ingestion can lead to ear ringing and dizziness, Reye’s syndrome (adolescents) • Allergic reactions result in anaphylaxis -- asthmatics may be at risk for reactions • Should be avoided w/ contact sports as it prolongs clotting time
Nonsteroidal Anti-inflammatory Drugs (NSAID’s) • Anti-inflammatory, antipyretic and analgesic properties • Inhibit prostaglandin synthesis and effective for osteo- and rheumatoid arthritis • Used primarily to reduce pain, stiffness, swelling, redness, fever associated w/ localized inflammation • Fewer side effects and longer duration than aspirin
Should not be used in place of acetaminophen or aspirin for headaches or increased temperature • Individuals w/ nasal polyps, associated bronchospasm or history of anaphylaxis should not receive NSAID’s • Can cause GI reactions, headache, dizziness, depression, tinnitus, • Taken in conjunction w/ heavy alcohol use can produce stomach bleeding
Corticosteroids • Used primarily for chronic inflammation of musculoskeletal and joint problems • Prolonged use can create complications • Fluid and electrolyte disturbances • Musculoskeletal and joint impairment • Dermatological problems • Neurological impairment • Endocrine dysfunction • Ophthalmic conditions • Metabolic impairment • Cortisone is primarily injected • Can have negative effect on ligaments and tendons • Also administered through iontophoresis and phonophoresis
Drugs that Produce Skeletal Muscle Relaxation • Include methocarbamol (Robaxin) and carisoprodol (Soma) • Due to overall relaxation effect, physicians believe these are less specific to muscle relaxation than once believed (also cause drowsiness) • Used to eliminate muscle guarding and spasm • Do not appear to be superior analgesics or sedatives in either acute or chronic conditions
Drugs Used to Treat Gastrointestinal Disorders • Includes stomach upset, gas formation due to food incompatibilities, acute or chronic hyperacidity • Poor eating habits may lead to digestive dysfunction such as diarrhea or constipation • Antacids • Neutralize acidity in upper GI, reducing pepsin activity (particularly on mucosal nerve endings • Relief of acid indigestion, heart burn, peptic ulcers
Sodium bicarbonate or baking soda are popular • Antacids w/ magnesium tend to have laxative effect • Those w/ aluminum and calcium cause constipation • Overuse can cause electrolyte imbalance • Antiemetics • Used to treat nausea and vomiting • Working Locally • Work on mucosal lining of stomach (may be more placebo) • Working Centrally • Affect brain, making it less sensitive to nerve impulses from inner ear and stomach • Variety of meds available, but may cause drowsiness
Carminatives • Provide relief from flatulence (gas) • Inhibit gas formation and aid in expulsion • Cathartics (laxatives) • Must be under direct supervision of physician • Constipation may be symptomatic of serious disease • Indiscriminate use may render athlete unable to have normal bowel movements • May cause electrolyte imbalance • Antidiarrheals • Diarrhea tends to be a symptom, not a disease • Result of emotional stress, allergies, adverse drug reactions, or different intestinal problems
Antidiarrheal (continued) • Acute diarrhea • Accompanied by chills, vomiting, intense abdominal cramps/pain • Will typically run course and stop when irritating agent removed from system • Chronic diarrhea • May lasts for days or weeks and may be the result of more serious disease states • Treat with Kaolin (absorb chemicals and pectin), substances that add bulk to stool • Systemic agents (except Imodium AD) are prescription drugs • Most are opiate derivatives and will cause drowsiness, dry mouth, and constipation • Do not treat antibiotic induced diarrhea as it may be protective symptom in antibiotic induced psuedomembranous colitis
Histamine-2 Blockers • Reduce stomach acid output by blocking histamine on certain stomach cells • Used to treat peptic and gastric ulcers and GI hypersecretory conditions • Drug examples include Cimetidine (Tagamet) and ranitidine (Zantac)
Drugs Used to Treat Colds and Allergies • Nasal Decongestants • Number of topical nasal decongestants available • Prolonged use may cause rebound congestion and dependency • Antihistamines • Often added to decongestants • Opposes histamine actions, but have little effects on the common cold • Beneficial in allergies • Impairs body’s ability to dissipate heat
Cough Medications • Suppress cough (antitussives) or produce fluid in respiratory system (expectorant) • Few side effects from nonnarcotic antitussives and are not addictive • Little evidence that expectorants are any more effective on reducing cough than simply drinking water • Sympathomimetics • May cause heat related problems • Epinephrine (Epipen) • ATC’s can receive instruction on use • Used to treat anaphylaxis resulting from food or insect bites
Drugs to Control Bleeding • Vasoconstrictors • Most often administered externally at sites of profuse bleeding • Epinephrine or adrenaline commonly used • Acts immediately, constricting vessels --very valuable in instances of epistaxis (nosebleed) • Hemostatic Agents • Drugs that immediately inhibit bleeding (under investigation) • Thrombin
Anticoagulants • Heparin • Prolongs clotting time but will not dissolve clot once formed • Controls extension of a thrombus already present • Coumarin derivatives • Acts by suppressing formation of prothrombin in the liver • Given orally, they can be used to slow clotting time in certain vascular disorders
Drugs that Can Increase the Rate of Heat Illness • Some drugs may alter the body’s ability to thermoregulate • Anticholinergics and antihistamines (decrease sweating mechanism) • Sympathomimetic amines (may predispose athlete to heat stroke) • Phenothiazines (impacts hot/cold temp. regulation) • Diuretics (alters volume expansion and cutaneous vasodilation) • ATC must be aware of potential risk of medications relative to heat illnesses
Substance Abuse Among Athletes • Drug use and performance enhancing agents in athletics • Substance abuse has no place in athletics • Use and abuse of substances can have a profound effect on performance • Athletic trainer must be knowledgeable about substance abuse in athletic population and should be able to recognize signs that athlete may be engaged in substance abuse
Performance Enhancing Substances (Ergogenic Aids) • Stimulants • Used to increase alertness, reduce fatigue, increase competitiveness and hostility • Psychomotor stimulant drugs • Amphetamines and non-amphetamines • Produces rapid turnover of catecholamines, which have strong effect on nervous and cardiovascular systems, metabolic rates, temperature and smooth muscle • Sympathomimetic drugs • Work on adrenergic receptors (those that release catecholamines) • Cause mental stimulation and increased blood flow but can cause elevated blood pressure, headache, increased and irregular heart beat, anxiety and tremors