1	Chapter 17 Pharmacology
2	Scenario An 80-year-old woman has fallen and is experiencing severe pain. You observe obvious deformity of the hip. Her husband hands you a sack that contains her pill bottles, but he is too upset to tell you what she is being treated for.
3	Discussion Why is it important to understand the general actions of her home medications? What additional information will you need to obtain prior to treating her pain? How will the age of this patient affect your drug administration?
4	Ancient Health Care Pharmacology dates to 10,000 to 7,000 B.C. Medicinal herbs Medications mentioned in Bible Plant-derived drugs used in Middle Ages
5	Historical Trends in Pharmacology “Chemical medicine” born in 17^th century Studies of drug dosage in 19^th century Led to development of manufacturing plants to produce drugs
6	Modern Health Care Expansion of consumer health education Increased research Incentives to develop orphan drugs for treatment of rare, chronic diseases
7	Drugs Defined as: Any substance taken by mouth; injected into a muscle, blood vessel, or cavity of the body; inhaled; or applied topically to treat or prevent a disease or condition
8	Sources of Drugs Five major sources Plants (alkaloids, glycosides, gums, and oils) Animals and humans Minerals or mineral products Microorganisms Chemical substances made in laboratory
9	Drug Names Chemical name Generic name Nonproprietary name Trade name Brand or proprietary name Official name
10	Drug References American Medical Association (AMA) Drug Evaluation American Hospital Formulary Service (AHFS) Medication package inserts Mosby’s Drug Consult Physician's Desk Reference (PDR) Nursing Drug Reference (NDR) Electronic data bases FDA web page Medline PharmInfoNet web page Toxline
11	Drug Standards and Legislation Before 1906: Little control Pure Food and Drug Act, 1906 Shirley Amendment, 1912 Harrison Narcotic Act, 1914 Federal Food, Drug, and Cosmetic Act, 1938 Durham-Humphrey Amendment, 1952 Kefauver-Harris Amendment, 1962
12	Comprehensive Drug Abuse Prevention and Control Act, 1970 Also called the Controlled Substances Act (CSA) Superseded Harrison Narcotic Act of 1914 Classified drugs into five categories (schedules) based on: Potential for abuse and physical and psychological dependence Defined terms drug dependency and drug addiction Established education and treatment programs for drug abuse
13	Drug Schedules Schedule I High abuse potential No accepted medical use Schedule II High abuse potential Accepted medical uses Schedule III Less abuse potential than drugs in schedules I and II Accepted medical uses; may lead to some physical dependence or high psychological dependence
14	Drug Schedules Schedule IV Lower abuse potential than schedule III drugs Accepted medical uses; may lead to limited physical or psychological dependence Schedule V Low abuse potential compared to schedule IV drugs Accepted medical uses; may lead to limited physical or psychological dependence
15	Drug Regulatory Agencies In 1973 the Drug Enforcement Agency (DEA) became the sole drug enforcement organization in the U.S. Other regulatory bodies or services Food and Drug Administration Public Health Service Federal Trade Commission Canadian drug control International drug control
16	General Properties of Drugs Therapeutic effects Desirable drug actions Side effects Undesirable or harmful drug actions Drug interaction with other drugs Can produce unpredictable effects Drug actions are biochemical interaction between drug and tissue components
17	Pharmaceutical Phase Pharmaceutics Science of dispensing drugs Dissolution Rate at which a solid drug goes into solution after ingestion More rapid rate of dissolution = more quickly drug is absorbed
18	Pharmacokinetic Phase Pharmacokinetics How the body handles a drug over a period of time Absorption Distribution Biotransformation Excretion
19	Drug Absorption Movement of drug molecules from site of entry to general circulation Variables affecting drug absorption Absorbing surface Blood flow to the administration site Drug solubility pH Drug concentration Dosage form
20	Routes of Medication Administration Mode affects the rate of onset of action May affect the therapeutic response Drugs are given for local or systemic effects
21	Routes of Medication Administration Topical Enteral Pulmonary Parenteral
22	Enteral Route Drugs administered along GI tract Oral Rectal Nasogastric Safe, convenient, economical Least reliable and slowest route Food contents Emotional state Physical activity
23	Oral Absorption Rich blood supply, little absorption in mouth Nitroglycerin and some hormones administered by sublingual or buccal routes Rapidly dissolve in salivary secretions
24	Gastric Absorption Length of time a drug remains in the stomach varies depending on: pH of the environment Gastric motility
25	Absorption in the Small Intestine Rich blood supply and large absorption area Most drug absorption occurs in the upper portion of the small intestine
26	Rectal Absorption Effective for some medications Vascular surface area capable of drug absorption Erratic absorption may occur from: Rectal contents Local drug irritation Uncertainty of drug retention No hepatic alteration on first pass through body
27	Parenteral Administration Subcutaneous Intramuscular Intravenous Intradermal Intraosseous Endotracheal
28	Subcutaneous Administration An injection beneath skin into connective tissue or fat beneath dermis Used for small volumes of drugs (<0.5 mL) that do not irritate tissue Absorption rate is slow Can provide sustained effect
29	Intramuscular Administration Injection given into skeletal muscle Absorption occurs more rapidly than SC injection Greater tissue blood flow
30	Intravenous Administration An injection given directly into the bloodstream Bypasses absorption process Almost immediate effect Most IV drugs are administered slowly to help prevent adverse reactions
31	Intradermal Administration Injection just below the epidermis Primarily used for allergy testing and to administer local anesthetics
32	Intraosseous Administration An injection directly into the bone marrow cavity through an IO infusion system Agents circulate via bone’s medullary cavity Time from injection to onset of action similar to venous route
33	Endotracheal Administration Generally through an ET tube Drug delivery into the pulmonary alveoli Systemic absorption via lung capillaries Absorption almost as rapid as IV route Usually reserved for situations in which an IV line cannot be established
34	Endotracheal Administration Adult ET medications include: Lidocaine (Xylocaine) Epinephrine (Adrenalin) Atropine Naloxone (Narcan)
35	Pulmonary Route Drugs given by gas or fine mist (aerosol) Absorption in blood is rapid due to: Large surface area Rich alveolar capillary network Produces primarily local effects Occasionally unwanted systemic effects
36	Topical Route Drugs applied topically to skin and mucous membranes Usually rapidly absorbed to produce a local effect Only intact skin surfaces used to prevent systemic effects Massaging skin promotes drug absorption
37	Drug Distribution Transport of a drug through the bloodstream to body tissues and site of action Distribution rate depends on capillary permeability to drug Cardiac output and regional blood flow affect rate and extent of distribution
38	Drug Reservoirs Drugs accumulate at storage sites, form reservoirs by binding to specific tissues Two types of drug reservoirs: Plasma protein binding Tissue binding
39	Blood-Brain Barrier Single layer of capillary endothelial cells Line blood vessels entering the CNS Permits only lipid-soluble drugs to be distributed into brain and CSF e.g., general anesthetics and barbiturates Drugs poorly soluble in fat have trouble passing this barrier Cannot enter the brain e.g., many antibiotics
40	Placental Barrier Membrane layers separate blood vessels of mother and fetus Not permeable to many lipid-insoluble drugs Provides some protection to the fetus Allows passage of certain non-lipid-soluble drugs Steroids, narcotics, anesthetics, and some antibiotics Can affect developing embryo or neonate if given to pregnant mother
41	Biotransformation Process by which the drug is chemically converted to a metabolite Purpose is to "detoxify" a drug and render it less active Liver is primary site of drug metabolism If drug metabolism is delayed, drug accumulation and cumulative drug effects may occur
42	Excretion Elimination of toxic or inactive metabolites Organs of excretion Kidneys Intestine Lungs Sweat and salivary glands Mammary glands
43	Excretion by Kidneys Can be excreted in urine unchanged or as metabolite of its previous form Renal excretion Passive glomerular filtration Partial reabsorption Active tubular secretion
44	Excretion by the Intestine Drugs eliminated by biliary excretion After liver metabolism, metabolites are carried in bile, passed into duodenum, and eliminated with feces Some drugs are reabsorbed by the bloodstream, returned to the liver, and later excreted by the kidneys
45	Excretion by the Lungs Drugs that can be excreted by the lungs include General anesthetics Volatile alcohols Inhaled bronchodilators Factors that can alter elimination via the lungs are Rate and depth of respiration Cardiac output
46	Excretion through Mammary Glands Many drugs or their metabolites cross the epithelium of the mammary glands Are excreted in breast milk Breast milk is acidic (pH 6.5) Nursing mothers are cautioned against medication use
47	Factors that Influence Actions of Drugs Age Body mass Gender Environment Time of administration Pathological state Genetic factors Psychological factors
48	Pharmacokinetic Phase of Drug Action
49	Pharmacodynamics Study of how a drug acts on a living organism Pharmacologic response relative to the concentration of a drug at an active site in the organism
50	Pharmacodynamics Most drugs produce effects by: Drug-receptor interaction Agonists Antagonists Affinity Efficacy Types of receptors Drug-enzyme interaction Nonspecific drug interaction
51	Drug-Receptor Interaction Agonists Drugs that bind to a receptor and cause a physiological response Antagonists Drugs that bind to a receptor and whose presence prevents a physiological response or other drugs from binding
52	Plasma Level Profiles Relationship between plasma concentration and level of therapeutic effectiveness over time Depend on: Rate of absorption Distribution Biotransformation Excretion
53	Plasma Level Profiles Therapeutic range Concentration (dose) that provides highest probability of response Least risk of toxicity Some patients fail to respond to therapeutic doses Others may develop toxicity
54	Plasma Level Profiles
55	Biological Half-Life Time needed to metabolize or eliminate half of total amount of drug in body A drug is considered gone from the body after five half-lives have passed Affected by renal and hepatic function
56	Therapeutic Index Measures relative safety of a drug Ratio between: Lethal dose 50 (LD 50) Dose of a drug lethal in 50% of laboratory animals tested Effectiveness dose (ED 50) Dose that produces a therapeutic effect in 50% of a similar population TI = LD 50/ED 50 The closer the ratio to 1, the greater the danger in administering the drug to humans
57	Drug-Receptor Interaction Most drug actions Chemical interaction between drug and various receptors in body Most common form of drug action is the drug-receptor interaction Most drugs are thought to bind to drug receptors to produce their desired effect
58	Drug Interactions Variables influencing drug interaction: Intestinal absorption Competition for plasma protein binding Drug metabolism or biotransformation Action at the receptor site Renal excretion Alteration of electrolyte balance
59	Drug-Drug Interactions Some drug-drug interactions are dangerous Drugs associated with significant interactions: Blood thinners Tricyclic antidepressants Monoamine oxidase (MAO) inhibitors Amphetamines Digitalis glycosides Diuretics Antihypertensives
60	Drug Interactions Other factors influencing drug interactions: Drug-induced malabsorption of foods and nutrients Food-induced malabsorption of drugs Enzyme alterations that affect the metabolism of foods or drugs Alcohol consumption Cigarette smoking Food-initiated alteration of drug excretion
61	Drug Storage Refer to local protocol Drug potency can be affected by: Temperature Light Moisture Shelf life Controlled medications security
62	Paramedic Responsibilities Use correct medications and techniques Observe and document the effects of drugs Keep current on changes in pharmacology trends Maintain professional relationships with health care team
63	Paramedic Responsibilities Understand pharmacodynamics of drugs being administered Carefully evaluate patients for drug indications and contraindications Take a thorough patient medication history Consult with medical direction as needed
64	Components of a Drug Profile Drug names Classification Indications Pharmacokinetics Side/adverse effects
65	Components of a Drug Profile Dosages Routes of administration Contraindications Special considerations Storage requirements
66	Special Considerations Pregnant patients Pediatric patients Geriatric patients
67	Pregnancy Ratings for Drugs Category A Risk of fetal harm remote Category B Inconclusive risk in first trimester, no risk in later trimesters Category C Give only if potential benefit outweighs risk to fetus Category D Evidence of fetal risk; may be acceptable if life-threatening situation Category X Risk outweighs any benefit
68	Pediatrics Effects unpredictable in infants Drug doses weight related Higher doses of water-soluble drugs may be needed Less effective blood-brain barrier in infants Slow drug clearance, excretion Longer half-life
69	Elderly Patient Causes of noncompliance and medication errors: Expense Forgetfulness or confusion Symptoms disappear Errors in taking medications Noncompliance may be deliberate
70	Drugs that Affect the Nervous System
71	Autonomic Nervous System Effects of many drugs depend on: Which branch of ANS they act on Whether the ANS branch is stimulated or inhibited by drug therapy
72	Autonomic Nervous System CNS Brain Spinal cord PNS Cranial and spinal nerves and their branches Connects all parts of body to CNS
73	Types of Nerve Fibers Visceral afferent (sensory) Convey impulses from internal organs to CNS Visceral efferent (motor) Convey impulses from CNS to internal organs, glands, and smooth and cardiac muscle Somatic afferent (sensory) Convey impulses from head, body wall, and extremities to CNS Somatic efferent (motor) Convey impulses from CNS to striated muscles
74	Autonomic Nervous System Peripheral nervous system provides a double set of nerve fibers: Sympathetic (adrenergic) Exit from thoracic and lumbar regions Parasympathetic (cholinergic) Exit from cranial and sacral portions
75	Autonomic Nervous System Sympathetic nerve stimulation Excitatory effects in some organs Inhibits effects in others Parasympathetic stimulation Excitation in some organs Inhibition in others
76	Autonomic Nervous System Both systems function continuously Occasionally react in reciprocal fashion Most organs are dominantly controlled by one system
77	Overview of Nervous System
78	Pre- and Postganglionic Neurons A two-neuron chain exists in a series between the CNS and effector organs Preganglionic neuron located in the CNS Passes between CNS and ganglia Postganglionic neuron located in the periphery Passes between ganglia and effector organ Synapse Junction between two neurons
79	Autonomic Conduction Pathways
80	Acetylcholine (ACh) Neurotransmitter At junction between preganglionic fiber and synapse At junction between postganglionic fiber and effector cell Fibers that release ACh are known as cholinergic fibers All preganglionic fibers of autonomic division All postganglionic fibers of parasympathetic division
81	Norepinephrine Neurotransmitter between sympathetic postganglionic fiber and effector cell Adrenergic fibers Release norepinephrine Most postganglionic neurons of the sympathetic division are adrenergic
82	Nerve Impulse Transmission Acetylcholine combines with cholinergic receptors Nicotinic Excitatory response Muscarinic Excites or inhibits
83	Nerve Impulse Transmission Norepinephrine combines with alpha and beta receptors in effector organs Binds to and activates both types of receptor molecules More affinity for alpha receptors
84	Nerve Impulse Transmission Epinephrine is an adrenergic substance: Produced by adrenal medulla Nearly equal affinity for both receptors In tissues containing alpha- and beta-receptor cells, one type is more abundant Has a dominating effect
85	Nerve Impulse Transmission
86	Drugs that Affect the ANS
87	Classifications Cholinergic (parasympathomimetic) Cholinergic blocking (parasympatholytic) Adrenergic (sympathomimetic) Adrenergic blocking (sympatholytic)
88	Narcotic Analgesics and Antagonists Narcotic analgesics relieve pain Narcotic antagonists reverse the narcotic effects of some narcotic analgesics
89	Pain Components Sensation of pain Involves the nerve pathways and the brain Emotional response to pain Anxiety level Previous pain experience Age Gender Culture
90	Narcotics Contain or abstracted from opium Morphine: Chief alkaloid of opium Bind with opioid receptors in brain and other body organs Alters pain perception and emotional response to pain
91	Narcotics Undesirable effects Nausea and vomiting Constipation Urinary retention Cough reflex suppression Orthostatic hypotension CNS depression
92	Opioid Analgesics Morphine (morphine sulfate) Codeine (methylmorphine) Hydromorphone (Dilaudid, Dilaudid-HP) Meperidine (Demerol) Methadone (Dolophine, Methadose) Oxycodone (Percodan, Tylox, Percocet) Hydrocodone (Lortab) Propoxyphene (Darvon, Dolene)
93	Opioid Antagonists “Block” opioid analgesics Displace analgesics from receptor sites Examples: Naloxone (Narcan) Naltrexone (Trexan) Nalmefene (Revex)
94	Opioid Agonist-Antagonists Analgesic and antagonist effects Pharmacokinetic and adverse effects similar to morphine Lower dependency risk than opioids Less severe withdrawal symptoms May cause withdrawal symptoms in addicts
95	Nonnarcotic Analgesics Peripheral mechanism Interferes with local mediators released when tissue is damaged Mediators stimulate nerve endings Cause pain Nonnarcotic analgesics decrease nerve ending stimulation
96	Anesthetics CNS depressants Reversible action on nervous tissue Major categories of anesthesia: General Regional Local
97	Antianxiety Agents and Alcohol Antianxiety agents Reduce feelings of apprehension Nervousness Worry Fearfulness
98	Sedative-Hypnotic Agents Depress CNS Calming effect Sedatives and hypnotics differ by degree of CNS depression Agent may be sedative and hypnotic Depends on dose used
99	Alcohol CNS depressant Can produce sedation, sleep, and anesthesia Enhances sedative-hypnotic effects of other drugs Blood alcohol measured (mg/dL) Behavioral effects based on blood alcohol levels
100	Benzodiazepines Bind to receptors in cerebral cortex and limbic system Actions Anxiety reducing Sedative-hypnotic Muscle relaxing Anticonvulsant Schedule IV drugs
101	Benzodiazepines Commonly prescribed benzodiazepines Alprazolam (Xanax) Chlordiazepoxide (Librium) Clorazepate (Tranxene) Diazepam (Valium) Flurazepam (Dalmane) Prazepam (Centrax) Midazolam (Versed) Lorazepam (Ativan) Triazolam (Halcion)
102	Barbiturates Duration of action Ultra-short acting Short acting Intermediate acting Long acting
103	Miscellaneous Sedative-Hypnotic Drugs Not benzodiazepines or barbiturates More like barbiturates than benzodiazepines Examples Chloral hydrate (Noctec) Ethchlorvynol (Placidyl) Meprobamate (Equanil, Meprospan) Some antihistamines have sedative effects Hydroxyzine hydrochloride (Vistaril, Atarax)
104	Anticonvulsants Treat seizure disorders Mode of action not understood Choice of drug depends on: Type of seizure disorder Patient's drug tolerance Medication noncompliance common
105	CNS Stimulants Classified by site of action Cerebrum Medulla and brainstem Hypothalamic limbic regions Common CNS stimulant drugs Anorexiants Amphetamines
106	Psychotherapeutic Drugs Psychotherapeutic drugs include Antipsychotic agents Antidepressants Lithium Treat psychoses and affective disorders Schizophrenia, depression, and mania
107	Psychotherapeutic Drugs Neurotransmitters in CNS affecting emotion: Acetylcholine Norepinephrine Dopamine Serotonin Monoamine oxidase
108	CNS and Emotions Alterations in neurotransmitter levels associated with changes in mood and behavior Drug therapy alleviates symptoms Temporarily modifies unwanted behavior
109	Antipsychotic Agents Schizophrenia (primary use) Tourette syndrome Senile dementia associated with Alzheimer disease Antipsychotic (neuroleptic) drugs block CNS dopamine receptors
110	Antipsychotic Agents Classifications Phenothiazine derivatives Butyrophenone derivatives Dihydroindolone derivatives Dibenzoxapine derivatives Thienbenzodiazepine derivatives Atypical agents
111	Antidepressants Treatment of affective disorders (mood disturbances) Depression Mania Elation Tricyclic antidepressants and MAO inhibitors are prescribed for depression Lithium is preferred treatment for mania
112	Antidepressants Newer classes of antidepressants (second-generation drugs) have been developed Examples Bupropion (Wellbutrin) Fluoxetine (Prozac) Trazodone (Desyrel) Sertraline (Zoloft) Paroxetine (Paxil)
113	Tricyclic Antidepressants Increase levels (block reuptake) of norepinephrine and serotonin Examples Imipramine (Tofranil) Amitriptyline (Elavil)
114	MAO Inhibitors Central-acting monoamines, especially norepinephrine and serotonin are thought to cause depression and mania Monoamine oxidase is responsible for metabolizing norepinephrine within nerve MAO inhibitors block this enzyme, leading to increased norepinephrine levels
115	Lithium Alters sodium transport in nerve and muscle cells Affects norepinephrine and serotonin Antimanic effects are thought to result from: Increased norepinephrine uptake Increased serotonin receptor sensitivity
116	Drugs for Specific CNS-Peripheral Dysfunction Parkinson disease Muscle rigidity Tremors Suspected cause: Low dopamine levels Huntington disease Progressive dementia Involuntary muscle twitching Dopamine, acetylcholine imbalance
117	Drugs with Central Anticholinergic Activity Inhibit or block acetylcholine Anticholinergic Restore brain’s dopamine-acetylcholine balance Examples Benztropine (tablets and injections) Ethopropazine hydrochloride
118	Drugs Affecting Brain Dopamine Three classifications Those that release dopamine Those that increase brain levels of dopamine Dopaminergic agonists
119	Skeletal Muscle Relaxants Central acting Baclofen (lioresal) Cyclobenzaprine (flexeril) Diazepam (valium) Direct acting Dantrolene (Dantrium) Neuromuscular blockers Can cause paralysis Pancuronium (Pavulon), vecuronium (Norcuron) Succinylcholine (Anectine)
120	Drugs Affecting the ANS Autonomic drugs Mimic or block effects of sympathetic and parasympathetic divisions of autonomic nervous system
121	Autonomic Drugs Cholinergic drugs Parasympathomimetic Mimic parasympathetic nervous system Cholinergic-blocking drugs Parasympatholytic Block parasympathetic nervous system
122	Autonomic Drugs Adrenergic drugs Sympathomimetic Mimic sympathetic nervous system (adrenal medulla) Adrenergic-blocking drugs Sympatholytic Block actions of sympathetic nervous system (adrenal medulla)
123	Receptors Catecholamines act on alpha and beta receptors Alpha 1 Alpha 2 Beta 1 Beta 2 Norepinephrine Acts mainly on alpha receptors Epinephrine Acts on alpha and beta receptors
124	Alpha and Beta Activities Alpha activities Vasoconstriction Arterioles in the skin and splanchnic area Pupil dilation Relaxation of the gut Beta activities Cardiac acceleration and increased contractility Vasodilation of skeletal muscle arterioles Bronchial relaxation Uterine relaxation
125	Alpha-Blocking Drugs Block the vasoconstricting effect of catecholamines Used in certain cases of hypertension Prevent necrosis after norepinephrine (Levophed) or dopamine (Intropin) extravasation into tissues Limited use in prehospital setting
126	Beta-Blocking Agents Block beta receptors Selective beta 1 blockers Metoprolol, atenolol Treatment of hypertension, angina Nonselective beta blockers Nadolol, propranolol, labetalol Antianginal, antihypertensives
127	Cardiac Drug Terminology Chronotropic drugs Affect heart rate Dromotropic drugs Affect conduction velocity through the conducting tissues of the heart Inotropic drugs Affect force of contraction
128	Cardiac Glycosides Positive inotropic effect Increase contractility Negative chronotropic effect Slow heart rate Negative dromotropic effect Slow conduction velocity Digoxin (Lanoxin) Small therapeutic index Side effects common
129	Antidysrhythmics Treat and prevent disorders of cardiac rhythm Work by: Direct action on the cardiac cell membrane (lidocaine) Indirect action that affects the cell (propranolol) Both
130	Antidysrhythmics—Classifications Based on mode of action on cardiac muscle Drugs that belong to the same class do not produce identical actions All antidysrhythmics can suppress automaticity
131	Class I Sodium Channel Blockers Class I-A Decrease conduction velocity Prolong electrical potential of cardiac tissue Procainamide (Pronestyl) Class I-B Decrease or have no effect on conduction velocity Lidocaine (Xylocaine) Class I-C Profoundly slow conduction Control life-threatening ventricular dysrhythmias Flecainide (Tambocor)
132	Class II Beta-blocking agents Reduce adrenergic stimulation of the heart Negative chronotrope Propranolol (Inderal)
133	Class III Potassium channel blockers Increase contractility Do not suppress automaticity Have no effect on conduction velocity Terminate dysrhythmias that result from reentry of blocked impulses Amiodarone (Cordarone)
134	Class IV Calcium channel blockers Block inflow of calcium through cell membranes of cardiac and smooth muscle cells Depresses the myocardial and smooth muscle contraction Decreases automaticity and in some cases decreases conduction velocity Diltiazem (Cardizem)
135	Antihypertensives Diuretics Sympathetic blocking agents (sympatholytic drugs) Vasodilators Angiotensin-converting enzyme (ACE) inhibitors Calcium channel blockers Angiotensin II receptor antagonists
136	Diuretics Renal excretion of excess salt and water Thiazide diuretics Moderately effective in lowering blood pressure Hydrochlorothiazide (HCTZ) Loop diuretics Short-acting agents that inhibit sodium and chloride reabsorption in loop of Henle Furosemide (Lasix) Potassium-sparing diuretics Less potassium loss than other diuretics Spironolactone (Aldactone)
137	Sympathetic Blocking Agents Beta-blocking agents and adrenergic-inhibiting agents Beta-blocking agents Treatment of suspected myocardial infarction, high-risk unstable angina, and hypertension Atenolol (Tenormin), metoprolol (Lopressor) Labetalol (Normodyne, trandate), nadolol (Corgard)
138	Adrenergic Inhibiting Agents Centrally acting adrenergic inhibitors Clonidine hydrochloride (Catapres) Peripheral adrenergic inhibitors Doxazosin (Cardura) Mechanism by which many of these agents work is unknown
139	Vasodilator Drugs Act directly on the smooth muscle walls of arterioles, veins, or both Lower peripheral resistance and blood pressure Arteriolar dilator drugs Hydralazine (Apresoline) Arteriolar and venous dilator drugs Nitroglycerin sublingual tablet (Nitrostat)
140	Angiotensin-Converting Enzyme (ACE) Inhibitors Angiotensin II is a powerful vasoconstrictor: Raises blood pressure Causes the release of aldosterone Contributes to sodium and water retention Inhibits conversion of angiotensin I to angiotensin II (brought about through ACE) Renin-angiotensin-aldosterone system is suppressed Blood pressure is lowered Captopril (Capoten)
141	Calcium Channel Blockers Inhibit contractility of vascular smooth muscle Reduce peripheral vascular resistance Dilate coronary vessels Verapamil (Isoptin) Diltiazem (Cardizem)
142	Angiotensin II Receptor Antagonists Selectively inhibit angiotensin II receptors Lower systolic and diastolic BP Candesartan (Atacand) Irbesartan (Avapro) Losartan (Cozaar, Hyzaar)
143	Monoamine Oxidase (MAO) Inhibitors Block release of norepinephrine at the sympathetic junction Interfere with vasoconstriction Reduce peripheral vascular resistance Decrease blood pressure Not widely used to treat hypertension
144	Antihemorrheological Agents Used to treat peripheral vascular disorders caused by pathological or physiological obstruction
145	Antihemophilic Agents Hemophilia Hemophilia A (classic hemophilia) is caused by a deficiency of factor VIII Hemophilia B (the “Christmas disease”) results from a deficiency in factor IX complex Replacement therapy of the missing clotting factor can be effective in the management of hemophilia Factor VIII (Factorate) Factor IX (Konyne) Antiinhibitor coagulant complex (Autoplex)
146	Drugs that Affect the Blood Drugs that affect blood coagulation may be classified as: Antiplatelet agents Anticoagulant agents Fibrinolytic agents
147	Antiplatelet Agents Interfere with platelet aggregation Prevention of clots, MI, stroke Treatment of valvular disease, shunts Include: Aspirin Dipyridamole (Persantin) Abciximab (ReoPro)
148	Anticoagulants Used to prevent intravascular thrombosis Decreases blood coagulability Examples Heparin (Liquaemin) Coumadin (Warfarin)
149	Fibrinolytic Agents Used to dissolve clots after formation Used for some acute myocardial infarcts Used in some stroke patients Examples Streptokinase Tissue plasminogen activator (t-PA) Reteplase (Retavase) Alteplase (Activase) Tenecteplase (TNKase)
150	Hemostatic Agents Hasten clot formation to reduce bleeding Systemic hemostatic agents Control rapid blood loss after surgery by inhibiting fibrinolysis Topical hemostatic agents Control capillary bleeding during surgical and dental procedures
151	Blood and Blood Components Replacement therapies Whole blood (rarely used) Packed red blood cells Fresh-frozen plasma Plasma expanders (Dextran) Platelets Coagulation factors Fibrinogen Albumin Gamma globulins
152	Antihyperlipidemic Drugs Hyperlipidemia: Excess lipids in plasma Used in conjunction with diet and exercise to control serum lipid levels Examples Atorvastatin (Lipitor) Cholestyramine (Questran) Niacin (Nicobid) Pravastatin (Pravachol) Lovastatin (Mevacor) Simvastatin (Zocor)
153	Bronchodilators Primary treatment for obstructive pulmonary disease Asthma, chronic bronchitis, and emphysema Classified as: Sympathomimetic drugs Xanthine derivatives Many agents are administered by inhalation via a nebulizer or pressure cartridge
154	Sympathomimetic Drugs Nonselective adrenergic drugs Have alpha, beta-1 (cardiac), and beta-2 (respiratory) activities Epinephrine (Adrenalin, Asmolin) Nonselective beta-adrenergic drugs Have both beta-1 and beta-2 effects Isoproterenol inhalation aerosol (Isuprel) Selective beta-2 receptor drugs Act primarily on beta-2 receptors in the lungs Albuterol (Proventil, Ventolin)
155	Xanthine Derivatives Xanthine drugs include caffeine, theophylline, and theobromine Actions Relax smooth muscle (particularly bronchial smooth muscle) Stimulate cardiac muscle and CNS Increase diaphragmatic contractility Promote diuresis through increased renal perfusion
156	Other Respiratory Drugs Prophylactic asthmatic agents Cromolyn sodium (Intal) Aerosol corticosteroid agents Beclomethasone dipropionate (Vanceril inhaler, Beclovent) Muscarinic antagonists Ipratropium (Atrovent) Antileukotrienes Montelukast (Singulair)
157	Mucokinetic Drugs Move respiratory secretions and sputum along tracheobronchial tree Alter consistency of secretions so that they can more easily be removed from the body Diluents (water, saline) Expectorants (Mucomyst)
158	Oxygen Treatment of hypoxia and hypoxemia Colorless, odorless, and tasteless gas essential for sustaining life
159	Respiratory Stimulants Direct stimulants (analeptics) Act on medullary center of brain Increase rate and depth of respirations Reflex respiratory stimulants Spirits of ammonia only inhalation drug given as a reflex respiratory stimulant Administered during cases of fainting
160	Respiratory Depressants Includes opium and barbiturate groups Respiratory depression is a common side effect Seldom given to intentionally inhibit rate and depth of respiration
161	Cough Suppressants Cough is a protective reflex to expel harmful irritants It may be: Productive (removes airway secretions) Nonproductive (dry and irritating) Antitussive agents Narcotic agents (codeine) Nonnarcotic agents Benzonatate (Tessalon)
162	Antihistamines Chemical mediator in most body tissues Highest in the skin, lungs, and GI tract Body releases histamine if exposed to antigen Antihistamines compete with histamine for receptor sites Prevent action of histamine
163	Antihistamines H 1 receptors Act primarily on blood vessels and bronchioles H 2 receptors Act mainly on GI tract Anticholinergic or atropine-like action
164	Antihistamines Primary clinical use is for allergic reactions Also for motion sickness, sedative, antiemetic Examples Dimenhydrinate (Dramamine) Diphenhydramine (Benadryl) Promethazine (Phenergan)
165	Serotonin Naturally occurring vasoconstrictor In platelets and in cells of brain and intestine Serotonin is not administered as a drug Has a major influence on other drugs and some disease states Helpful in repairing damaged blood vessels Stimulates smooth muscle contraction Acts as a neurotransmitter in the CNS
166	Antiserotonins Antiserotonins (serotonin antagonists) work to inhibit responses to serotonin and its influence on other drugs and disease states Vascular headache, allergic disorder treatment Cyproheptadine (Periactin) Methysergide maleate (Sansert)
167	Drugs Affecting the GI System Antacids (Alka-Seltzer) Antiflatulents (Mylicon) Digestants (Pancrease) Emetics (syrup of ipecac)
168	Drugs Affecting the GI System Antiemetics Compazine, Phenergan Cytoprotective agents Protect cells from damage Cytotec, Carafate
169	Drugs Affecting the GI System H2 receptor antagonists Reduce volume and acidity of gastric acid Zantac, Tagamet, Pepcid Proton pump inhibitors Treat symptomatic gastroesophageal reflux disease, esophagitis Nexium, Prevacid, Prilosec, Aciphex
170	Drugs Affecting the Lower GI Tract Laxatives Constipation causes: Neurological disease, pregnancy, rectal disorders, surgery, drug poisoning Epsom salt, Dulcolax, Colace Antidiarrheals Adsorbents (Pepto-Bismol) Anticholinergics (Donnatal) Opiates (paregoric) Other (Lomotil, Imodium)
171	Drugs Affecting the Eye Antiglaucoma agents Pilocarpine, acetazolamide Mydriatic and cycloplegic agents Treat inflammation, relieve pain Atropine, homatropine opthalmic solution
172	Drugs Affecting the Eye Antiinfective/antiinflammatory agents Treat conjunctivitis, sty, keratitis Topical anesthetic agents Prevent pain, rapid onset Proparacaine HCl, tetracaine HCl
173	Drugs Affecting the Ear Antibiotics for infection Chloramphenicol Steroid/antibiotic combinations Superficial bacterial infections Cortisporin Otic Miscellaneous preparations Treat ear wax, fungal infections, inflammation
174	Drugs Affecting the Endocrine System Endocrine system works to control and integrate body functions Natural chemicals (hormones) are produced by endocrine glands
175	Drugs Affecting the Pituitary Anterior and posterior pituitary gland hormones regulate secretion of other hormones Anterior pituitary drugs Treat growth failure in children caused by growth hormone deficiency Posterior pituitary drugs Treat symptoms of diabetes insipidus due to antidiuretic hormone deficiency
176	Drugs Affecting the Thyroid Thyroid hormone controls rate of metabolic processes Required for normal growth and development Parathyroid hormone regulates level of ionized calcium in blood through: Release of calcium from bone Absorption of calcium from the intestine Rate of excretion of calcium by the kidneys
177	Thyroid Gland Disorders Goiter Enlargement of thyroid Hypothyroidism Thyroid hormone deficiency Hyperthyroidism Thyroid hormone excess Drugs to treat hypothyroidism and prevent goiters Thyroid (Synthroid) Iodine products Levothyroxine
178	Parathyroid Disorders Hypoparathyroidism and hyperparathyroidism Drugs to treat hyperparathyroidism Vitamin D Calcium supplements
179	Drugs Affecting the Adrenal Cortex Adrenal cortex secretes steroid hormones Glucocorticoids (cortisol) Raise blood glucose Deplete tissue proteins Suppress the inflammatory reaction Mineralocorticoids (primarily aldosterone) Regulate electrolyte and water balance Sex hormones Little physiological effect under normal circumstances
180	Drugs Affecting the Pancreas Hormones of the pancreas Insulin Primary hormone that regulates glucose metabolism Glucagon Stimulates liver to break down glycogen so that glucose is released into the blood Also inhibits uptake of glucose by muscle and fat cells
181	Drugs Affecting the Pancreas Insulin Preparations Rapid acting Insulin lispro Insulum aspart Short acting Regular Intermediate acting Lente Insulin NPH Insulin Long acting Ultralente Insulin glargine Oral Hypoglycemic Agents Amaryl Glucophage Glucotrol Micronase Oral Combination Agents Glucovance Metaglip Avandamet
182	Drugs Affecting the Pancreas Hyperglycemic Agents Glucagon Diazoxide (Proglycem) Dextrose Oral glucose (Glutose, Insta-Glucose)
183	Drugs Affecting the Reproductive System Includes synthetic and natural substances Hormones Female Male
184	Female Sex Hormones Two hormones secreted by ovary: Estrogen Progesterone Supplemental estrogen indicated for: Estrogen deficiency or replacement Treatment of breast cancer Prophylaxis for osteoporosis in postmenopausal women Progesterone (and synthetic progestins) used to: Treat hormonal imbalance Treat endometriosis Treat specific cancers Prevent pregnancy when properly used
185	Oral Contraceptives Oral contraception most effective form of birth control Commonly known as “the pill” Combination of estrogen and progesterone that results in suppression of ovulation Available in several different forms
186	Ovulatory Stimulants and Infertility Drugs Absence of ovulation (anovulation) may be a pathological condition in women with abnormal bleeding or infertility Sometimes treated with: Gonadotropins Thyroid preparations Estrogen Synthetic agents
187	Drugs Affecting the Male Reproductive System Testosterone therapy Indicated for treatment of: Hormone deficiency (e.g., testicular failure) Impotence Delayed puberty Female breast cancer Anemia
188	Drugs Affecting Sexual Behavior Drugs that impair libido and sexual gratification Includes some antihypertensives, antihistamines, antispasmodics, sedatives, tranquilizers Drugs that enhance libido and sexual gratification Levodopa (L-dopa) Sildenafil (Viagra)
189	Drugs Used in Neoplastic Diseases Antineoplastic agents Used in cancer chemotherapy to prevent proliferation of malignant cells Do not directly kill tumor cells Interfere with cell reproduction or replication Examples Adrucil Mustargen Amethopterin
190	Antibiotics Treat local or systemic infection Kill or suppress growth of microorganisms Disrupt bacterial cell wall Disturb functions of cell membrane Interfere with cell’s metabolic functions Includes: Penicillins Cephalosporins and related products Macrolide antibiotics Tetracyclines Miscellaneous antibiotic agents
191	Antifungal Drugs Some fungi are always present in body Mouth, skin, intestines, and vagina Prevented from multiplying through competition from bacteria and from actions of the immune system Infection occurs when person becomes immunocompromised Tinactin, Diflucan, Mycostatin
192	Antiviral Drugs Few effective drugs to treat minor viral infections Viral infections range from harmless (e.g., warts) to serious diseases Often have toxic effects Acyclovir (Zovirax) Zidovudine (Retrovir) Lamivudine; zidovudine (Combivir)
193	Protease Inhibitors Complete mechanism of action not clear Appear to inhibit replication of retroviruses (e.g., HIV) in acute and chronically infected cells Side effects and adverse reactions Indinavir (Crixivan) Ritonavir (Norvir)
194	Analgesic-Antipyretic Drugs Antipyretics reduce fever Analgesic-antipyretic drugs work by reversing the effect of the pyrogen on the hypothalamus Analgesics act on peripheral pain receptors to block activation Acetaminophen Aspirin
195	Nonsteroidal Antiinflammatory Drugs Aspirin is the prototype of the NSAIDs Inhibit enzymes so that prostaglandins (substances that promote inflammation and pain) are not formed Aspirin Ibuprofen Naproxen Ketorolac Celecoxib
196	Drugs Affecting the Immunological System Immunosuppressants Antirejection, anticancer, corticosteroid drugs Immunomodulating agents Serums Vaccines
197	Conclusion To ensure maximum effectiveness and reduce the potential for harm, the paramedic must have a thorough understanding of drugs and their actions before they are administered.
198	Questions?