PHARMACOLOGY REVIEWER PHARMACOLOGY Greek: pharmakon + logos Study of drugs and their actions Study of biologic effect of chemicals DRUGS roog roog meaning dry Dutch: d Chemical substances that have an effec t on living organisms Therapeutic drugs PHARMACOTHERAPEUTICS Clinical pharmacology Branch of pharmacology involvin g drugs used to treat, prevent or diagnose disease MEDICINES Therapeutic drugs Sources o Plants o Animal products o Inorganic compounds o Synthetic sources ROLE IN NURSING CARE 1. PREVENTION - First level - Health impact of environmen t social, medicinal and illegal drug abuse - Health aspects of 2.
EARLY DETECTION OF DI SRUPTION IN A HEALTHY CLIENT - Second level - Case finding and referral habituation, toxicity addiction and untoward side effects - Seeks evidence of
3.
CARE NEEDED FOR CLIENTS WITH ACUTE HEALTH NEED S - Third level - Institutional setting - Administering drugs to acutely ill pa tients
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REHABILITATION AND RESUMPTION OF NORMAL LIVING - Fourth level - Focus education and assistance drugs necessary - Long term use of
PHARMACOLOGY IN NURSING EDUCATION Integrated in curriculum PHARMACOLOGY IN RESEARCH Drug research Considerations in drug research o Nurse
Fully informed o Information available to physician o Research and pharmacist o Recommended dosage o Route of administration o Desired therapeutic effects o Adhere to the study protocol ETHICAL PRINCIPLES Respect for person o Individuals are independent meaning they are capable of making decisions BENEFICENCE duty to do no harm JUSTICE social benefits can be alloca ted objectivel y and that those with equivalent circumstances should be treated equally
PRINCIPLES OF DRUG ADMINISTRATION NURSE- should understand professional responsibilities Medical administrations Medication deliver y systems Durg orders DRUG DISTRIBUTIONS SYTEM 1.
FLOOR STOCK - All medications are stocked at nursing station - Except dangerous drugs - Utilized in small hospitals, government hospitals
2.
INDIVIDUAL PRESCRIPTION PRDER SYSTEM - Medications dispensed form pharmacy - Receipt prescription or drug order
3.
COMPUTER-CONTROLLED DISPENSING SYSTEM - Drug order sent to pharmacy - Encode order to a computer system security code and password access the system - Nurse with the use of
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UNIT DOSE SYSTEM drugs - Single unit packages of - Dispensed to fell each dose required - Individual packages placed in individual labelle d drawers kept in - Refilled every 24 hours and large unit dose cabinet; 3 to 7 days in long term facilities
NARCOTIC CONTROL SYSTEM Within hospitals It is a standard policy that controlled substances are issued in single unit packages and are kept in separate locked cabinet in each nursing unit Head nurse designated individuals is responsible for the key When controlled substances are issued to a nursing unit DRUG ORDERS y
STAT - emergency doses
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- Meds given ASAP but ONCE only SINGLE ORDER - Administration at a certain time only but once STANDING ORDER doses - Meds given for a specific number of PRN (pro re nata) - For the thing born - As needed - Allows nurse to practice judgement to when a medication should be administered VERBAL ORDERS Should be avoided Physician should co-sign and date the order in 24 hours
RESPONSIBILITIES IN DRUG THERAPY RIGHT 1. 2. 3. 4. 5. 6.
Patient Drug Time Dose Route Administration
LEGAL AND ETHICAL Practice under professional license PATIENTS CHART Primary source of information THE NURSING PROCESS ASSESSMENT Subjective and objective Prescriptions OTCs Herbals Responses to medications NURSING DIAGNOSIS Decision about the needs/problems of patient Critical thinking, creativity and accurate data PLANNING Goals and outcome criteria Specific and measurable Patient-centered Time-frame Prioritization IMPLEMENTATION Initiation and completion of nursing plans LEGAL REGULATIONS OF PHARMACOLOGY
1.
US PHARMACOPEIA (USP) - Drug standard revised every 5 years - Drugs have high standards for therapeutic use - International Pharmacopeia first published in 1951
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FEDERAL LEGISLATION - Public protected from drugs that are impure, toxic, ineffective or not tested prior to public use
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FOOD, DRUG AND COSMETIC ACT 1938 drug - To monitor and regulate the manufacture and marketing of ul effects have label wi th accurate - It is FDAs responsibili ty to ensure that all drugs are tested for harmf information, an enclose with drugs packaging detaile d literature that explains adverse effects
4.
DURHAM-HUMPHREY AMENDMENT 1938 (1952) - Distinguishes between drugs that are solid with or without prescription and those that should not be refille d without new prescription
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KEFAUVER-HARRIS AMENDMENT OF 1938 (1962) the 1950s - Resulted from the Thalidomide tragedy of Taken during first trimester Babies were born with extreme limb deformities
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COMPREHENSIVE DRUG ABUSE PREVENTION AND CONTROL ACT - Categorize substances into schedules
CONTROLLED SUBSTANCES ACT drug abuse, included several provi sions Designed to remedy the escalating problem of drug education and research into the prevention and treatment of drug dependence o Promotion of Strengthening of enforcement authority o treatment and rehabili tation facili ties o Establishment of schedules or categories for controlled substances according to abuse liabili ty o Designation of o CONTROLLED SUBSTANCES SCHEDULE I- not approved for medical use, abuse potential and extent of physical and psychologic depen dence are greater with schedule I SCHEDULE II to V- have accepted medical use SCHEDULE V- limited potential and extent of physical and psychologic dependence CODEINE- schedule II but when added to acetaminophen it becomes a schedule II drugs and when it is used in combination as a cough preparation becomes schedule V drug NURSING INTERVENTION S: CONTROLLED SUBSTANCES y Account for all controlled drugs y Keep a special controlled-substance record for required information y Countersign all discarded or wasted medication y Ensure that records and drugs on hand match y Keep all controlled drugs locked up; narcotics must be kept under double lock y Be certain that only authorized persons have access to the keys o the DOJ- charged with the role of being the nations sole DRUG ENFORCEMENT ADMINISTRATION of legal drug enforcement agency 8. DRUG REGULATION REFORM ACT1978 Shortened the time in w hich new drugs could be developed and marketed 9. DRUG RELATIONS ACCT 1992 drugs used to treat AIDS and cancer The regulations were change to increase the approval rate of Pharmaceutical companies pay a user fee at the time they file the application for the new drug 10. THE FOOD AND DRUG ADMINI STRATION MODERNIZATION ACT 1997 7. -
FIVE PROVISIONS o Review and use of new drugs is accelerated o Drugs can be tested in children before marketing o Clinical trial data are necessary for experimental drug use for serious or life-threatening health conditions o Drug companies are required to give information on off-label drugs and their uses and costs o Drug companies that plan to discontinue drugs must inform health professionals and clients at least 6 months before stopping drug production 11. HEALTH INSURANCE PORTABILITY AND ACCOUNTABILITY ACT (HIPPA) 2003 Sets te standards for the privacy of individually indentifiable health information as of 2003 health Gives clients more control over their health information, including boundaries on the use and release of records Limitations on access to information from the pharmacy Pharmacist must provide a private are for consultation with the client and have all clients sign a statement that they have received a copy of the privacy statement 12. PDIATRIC RESEARCH EQUITY ACT 2003 drugs and biologic products for safety and effectiveness in children by FDA is authorized to require testing of drug manufacturers One must not assume that children are small adults 13. MEDICARE PRESCRIPTION DRUG IMPROVEMENT AND MODERNIZATION ACT 2003 Serves to provide financial assistance to seniors to purchase needed prescription medications -
LEGAL REGULATIONS 1.
CANADIAN FOOD AND DRUG ACT OF 1953 - Schedule G and H - Advertising, labelling and quality SCHEDULE F- prescription drugs; no potential for abuse o SCHEDULE G- written prescription and refill s require written or verbal prescription; potential for abuse o and must have a G on the label SCHEDULE H- no recognized medical use and are potentially dangerous o
2.
WHEELER-LEA ACT OF 1938 drugs food and cosmetics - Non-fraudulent advertising of
3.
NURSE PRACTICE ACT - Cannot prescribe or administer drugs without MD order
LEGAL TERM 1. MISFEASANCE a. Negligence b. Nonfeasance c. Omission 2. MALFEASANCE a. Giving right drug by wrong route PHILIPPINE LAW S 1.
NATIONAL DRUG POLICY 1987 - Ensures drugs are safe, effective and essential - Reasonable and affordable
Components uality assurance of drugs o Q o drugs by health professionals and consumers Rational use of o Self reliance and self sufficiency o Targeted drug procurement by government in suppor t for the 1stof 3 pillars 2.
GENERIC ACT OF 1988 (RA 6675) - Identifies by their scientific and internationall y recognized active ingredients ADVANTAGES - Decreases prices - Ensures adequate drug supply - Promote safety drugs - For scientific basis use of DISADVANTAGES - Some have inert fillers and binders that may result in differences in effectiveness - May have some variation in action or response - Too long and difficult to pronounce
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SENIOR CITIZEN ACT Provision in which senior citizen will be given 20% discount RA 9502- UNIVERSALLY ACCESIBLE CHEAPER AND QUALITY MED S ACT OF 2008 Effective September 2008 drug prices thru free competition and better access to affordable brand Lowering of Generic forms to test, produce and register generic versions of patented drugs unknown drugs Prohibits ne patent of newly discovered uses of
CHAPTER 1 DRUG ACTION: PHARMACEUTIC , PHARMACOKINETIC AND PHARMACODYNAMIC PHA SES PHARMACEUTIC PHASE Dissolution- drugs in solid form must disintegrate into small particles to dissolve into a liquid Excipients fillers and inert substances; used in drug preparation to take on a par ticular size and shape and to enhance drug dissolution Disintegration- breakdown of a tables into smaller particles the smaller particles in the GI fl uid before absorption Dissolution dissolving of Rate limiting- the time it takes the drug to disintegrate and dissolve to become available for the body to absorb it ** drugs are both disintegrated and absorbed faster in acidic fluids with a pH of 1 or 2 rather than alkaline fl uids -
the stomach, so the disintegration does not Enteric-coated drugs- resist disintegration in the gastric acid of the small intestine; should not be crashed occur until the drug reaches the alkaline environmen t of
PHARMACOKINETIC PHASE drug movement to achieve drug action The process of 1. ABSORPTION drug particles from the GI tract to body fl uids by passive absorption, active absorption or - Movement of pinocytosis the small intestine through the action of the - Most oral drugs are absorbed into the surface area of extensive mucosal villi - Dec. number of villi = dec. absorption rugs- ( insulin and growth hormones) destroyed in the s.intestine by digestive enzymes - Protein-based d usion - PASSIVE ABSORPTION- occurs mostly by diff - ACTIVE ABSORPTION- requires a carrier such as an enz yme or protein to move the drug against a concentration gradient - PINOCYTOSIS- process by which cells carry drug across their membrane by engulfing the drug particles ** drugs that are fat soluble pass rapidly through the GI membrane ** weak acid drugs such as aspirin are less ionized in the stomach and they pass through the stomach lining easily and rapidly the antif ungals need an acidic environment to achieve greater ***calcium carbonate and many of absorption - FIRST-PASS EFFECT or HEPATIC FIRT PASS- process in which the drug passess to the liver first; example: Coumadin, morphine the administered drug that reaches the - BIOAVAILABILITY- subcategory of absorption; percentage of systemic circulation - FACTORS THAT ALTER BIOAVAILABILITY o Drug form o Route of admini stration o GI mucosa and motili ty o Food and other drugs o Changes in liver me tabolism
2.
DISTRIBUTION - Process by which the drug becomes available to body fl uids and body tissues - Influenced by blood flow, its affinity to the tissue and protein-binding effect - VOLUME OF DRUG DISTRIBUTION- dependent on drug dose and its concentration in the body - Larger Vd = longer half-life drug that is bound is inactive because it is not available to receptors, and the - FREE DUGS- por tion of portion that remains unbound; are active and can cause pharmacologic effect - Two highly protein bound drugs = drug accumulation and possible drug toxicity
3.
METABOLI SM OR BIOTRANSFORMATION -LIVER primary site of metabolism st drugs are inactivated by liver enzymes and are then converted or transformed by hepatic *** Mo enzymes to inactive metabolites or water-soluble substances for excretion the drug concentration to be elimina ted - HALF LIFE- the time it takes for one half of - SHORT HALF-LIFE= 4 to 8 hours - LONG HALF-LIFE= 24 hours or longer the drug for three to five half-lives saturates the biologic system to the extent that the - Admini stration of drugs equals the amount metabolized and excreted intake of therapeutic effect - STEADY- STATE SERUM CONCENTRATION is the predictive of
4.
EXCRETION or ELIMINATION - Main route of elimina tion is through the kidneys - KIDNEYS filter free, unbound drugs; water soluble drugs and drugs hat are unchanged - LUNGS eliminate volatile drugs substances and products metabolized to CO2 and H2O - ACID URINE promotes elimina tion of weak base drugs - ALKALINE URINE promotes elimination of weak acid drugs - ASPIRIN a weak acid; excreted rapidly in alkaline urine - SODIUM BICARBONATE antidote for aspirin - CRANBERRY JUICE- can decrease urine pH unction; varies with age and gender; - CREATININE CLEARANCE- most accurate test to determine renal f lower in elderly and female clients - CREATININE- me tabolic byproduct of muscles that is excreted by the kidneys - CREATININE CLEARANCE TEST 12 or 24 hour urine collection - NORMAL CREATININE CLEARANCE- 85 to 135ml/min unctioning nephrons - AGING- decreases muscle mass and results in a decrease in f
PHARMACODYNAMIC PHASE drug concentration and its effects on the body PHARMACODYNAMICS- the study of Primary effect may be desirable; secondary effect may be desirable or undesirable drug dose needed to DOSE RESPONSE- relationship between the minimal ver sus the maximal amount of produce the desired drug response ter a drug is administered ONSET OF ACTION- time it takes to reach the minimum effective concentration af PEAK ACTION- occurs when the drug reaches its highest blood or plasma concentration time the drug has a pharmacologic effect DURATION OF ACTION- the length of RECEPTORS- protein in structure; found on cell membranes LIGAND-BINDING- the site on the receptor in which dr ugs bind FOUR RECEPTOR FAMILIES o CELL MEMBRANE-EMBEDDED ENZYME S LIGAND BINDING DOMAIN- on the cell surface; the drug activates the enzyme and a response is initiated o LIGAND-GATED ION CHANNELS the drug spans the cell membrane an d with this receptor, the channel the cells. The ions are primarily sodium and calcium. opens, allowin g for the flow of ions into and out of o G PROTEIN-COUPLE RECEPTOR SYSTEMS Receptor
G protein than binds with guanosine triphosphate Effector that is either an enzyme or an ion channel o the cellmembrane TRANSCRIPTION FACTORS on the DNA in the cell nucleus and not on the surface of Drugs act through receptors by binding to the receptor to produce a response or to block a response the drug to bin to a specific receptor Activity of many drugs is determined by the ability of AGONISTS- drug that produce a response ANTAGONISTS- drugs that block a response CHOLINERGIC RECEPTORS- located in the bladder, heart, blood vessels, lungs and eyes NON SELECTIVE DRUGS- drugs that affect various sites FOUR CATEGORIES OF DURG ACTION STIMULATION OR DEPRESSION o STIMULATION- the rate of cell activity or secretion from a gland increases unction of a specific organ are reduced DEPRESSION-cell activity and f o REPLACEMENT- replace e ssential body compounds o INHIBIT OR KILL- interfere with bacterial cell growth o IRRITATION safety of a drug through the use of a ratio that measure the THERAPEUTIC INDEX- estimates the margin of effective dose and the lethal dose safety o LOW THERAPEUTIC INDEX- have a narrow margin of o safety and less danger of a producing toxic effec ts HIGH THERAPEUTIC INDEX- wi de margin of THERAPEUTIC RANGE- be tween the minimum effective concentration in the plasma for obtaining desired drug action and the minimum toxic concentration in the plasma for obtaining desired drug action and the minimum toxic concentration drug at a specific time PEAK DRUG LEVEL- highest plasma concentration of o Orally- 1 to 3 hours o IV- 10 minutes TROUGH LEVEL- lowest plasma concentration of a drug and it measures the rate at which the drug is eliminated LOADING DOSE- initial dose DIGITALIZATION- the process by which the minimum effective concentration level for digoxin is achieved in the plasma within a short time SIDE EFFECTS- physiologic effects not related to desired drug effects untoward effects that cause mild to severe side ADVERSE REACTIONS- more severe than side effects; a range of effects including anaphylaxis the drug TOXIC EFFECTS or TOXICITY- can be identifie d by monitoring plasma therapeutic range of genetic PHARMACOGENICS- effect of a drug action that varies from a predicted drug response because of factors or hereditary influence TACHYPHYLAXIS- drug tolerance to a frequently repeated administration of a certain drug PLACEBO EFFECT- psychologic benefi t from a compound that may not have the chemical structure of a drug effect
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PHARMACEUTIC
SOLID FORM LIQUID FORM
PHARMACOKINETICS ABSORPTION DISTRIBUTION METABOLISM OR BIOTRANSFORATION EXCRETION
PHARMACODYNAMICS DRUG ACTION RECEPTORS ENZYMES HORMONES
UNIT FIVE ADRENERGICS AND ADRENERGIC BLOCKERS AUTONOMIC NERVOU S SYSTEM AGENTS
the brain and spinal cord - CENTRAL NERVOUS SYSTEM- bodys primary nervous system that consists of - PERIPHERAL NERVOUS SYSTEM- located outside the brain and spinal cord heart, respiratory - AUTONOMIC NERVOU S SYTEM- acts on smooth muscles and glands; control and regulation of system, gastrointestinal tract, bladder, eyes and glands; an involuntary nervous - AUTONOMIC COMPONENTS OF THE PNS o AFFERENT NEURONS- sends impulses to the CNS where they are interpreted o EFFERENT NEURON S- receive the impulses from the brain and transmit those impulses through the spinal cord to the effector organ cells EFFERENT PATHWAYS SYMPATHETIC NERVOU S SYSTEM- also known as the ADRENERGIC NERVOUS SYSTEM o At one time it was believe d that adrenaline was the neurotransmitter that innervated the smooth muscle NOREPINEPHRINE the actual neurotransmitter o PARASYMPATHETIC NERVOUS SYSTEM- called the CHOLINERGIC SYSTEM the neuron that innervates the muscle is ACETYLCHOLINE Neurotransmitter at the end of Cholinergic receptors are either NICOTINIC or MU SCARINIC Drugs that mimic the neurotransmitters norepinephrine and acetylcholine produces response opposite to each other in the same organ
CNS
BRAIN
PNS
SPINAL CORD
ANS
SYMPATHETIC
SNS
PARASYMPATHETIC
BODY TISSUE/ORGAN
SYMPATHETIC RESPONSE
PARASYMPATHETIC RESPONSE
EYES LUNGS HEART BLOOD VESSELS GASTROINTESTINAL BLADDER UTERUS SALIVARY GLAND
Dilates pupils Dilates bronchioles Increases heart rate Constricts blood vessels
Constricts pupils Constricts bronchioles and increa ses secretions
Decreases heart rate Dilates blood vessels
Relaxes smooth muscles of GI tract
Increases peristalsis
Relaxes bladder muscle
Constricts bladder
Relaxes uterine muscle --------------
--------------Increases salivation
SYMPATHETIC STIMULANTS
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SYMPATHOMIMETIC S adrenergics, adenomimetics or adrenergic agonists
PARASYMPATHETIC STIMULANTS DIRECT ACTING -
PARASYMPATHOMIMETICS Cholinergics or cholinergic agonists Decrease blood pressure Decrease pulse rate Constrict brongchioles Constrict pupil of eyes Increase urinary contraction Increase peristalsis
Increase BP Increase PR Relax bronchioles Dilate pupils of eyes Relax uterine muscles Increase blood sugar
CHOLINESTERASE INHIBITORS Increase muscle ton
SYMPATHETIC DEPRESSANTS
PARASYMPATHETIC DEPRESSANTS
SYMPATHOLYTICS Adrenergic blockers, adrenolytics or adrenergic antagonists Decrease pulse rate Decrease blood pressure Constrict bronchioles
INDIRECT ACTING
PARASYMPATHOLYTICS Anticholinergics, cholinergic antagonists or anti spasmodic Increase pulse rate Decrease mucous secretions Decrease gastrointestinal motility Increase urinary retention Dilate pupils of eyes
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ACETYLCHOLINE- between nerves and muscles
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the sympathetic branch of ANS NOREPINEPHRINE AND EPINEPHRINE- ca techolamine. Relea sed in the nerves of
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DOPAMINE- increase in concentration in the brain for coordination of impulses (motor and intellectual)
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GABA- in brain; inhibits nerve activity
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SEROTONIN- limbic system; arousal and sleep; prevents depression and promotes motivation
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NOREPINEPHRINE adrenergic NS
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ACETYLCHOLINE cholinergic NS
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ADRENERGIC- stimulate the sympathetic nervous system; located throughout the body, alpha and beta receptors
CHAPTER 17 ADRENERGICS AND ADRENERGIC BLOCKERS y
ADRENERGICS- drugs that stimulate the sympathetic nervous system
they mimic the sympathetic neurotransmitters
they act on one or more adrenergic receptor sites located on the cells of smooth muscles, such the eye as the heart, bronchiole wall s, GI tract, urinary bladder and ciliary muscle of
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smooth muscles ALPHA-ADRENERGIC RECEPTORS- located in the vascular tissues (vessels) of
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STIMULATION OF ALPHA 1 RECEPTORS- arterioles and venules constrict. Thereby decreasing peripheral resistance and blood return to the heart improved circulation and increased blood pressure
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ALPHA2 RECEPTORS- located in the postganglionic sympathetic nerve endings
When stimulated it inhibits the release of norepinephrine thus leading to a decrease in vasoconstriction and this results to decrease in blood pressure
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BETA 1 RECEPTORS- located primaril y in the heart; stim ulation increases myocardial contractility and
heart rate o
the lung, the arterioles of skeletal muscles BETA 2 RECEPTORS- found mostly in the smooth muscles of and the uterine muscle
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Stimulation causes y
the smooth muscles of the lungs, resulting in bronchodilation Relaxation of
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An increase in blood flow to the skeletal muscles
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the uterine muscle, resulting in a decrease in uterine contractions Relaxation of
DOPAMINERGIC- located in renal, mesenteric, coronary and cerebral arteries o
When stimulated, the vessels dilate and blood flow increases ALPHA1 RECEPTOR
BLOOD VESSELS
EYE
VASOCONSTRICTION
MYRDIA SIS (PUPIL DILATION)
BLADDER
PROSTATE
CONTRACTION
CONTRACTION
INCREASED BP ALPHA2 RECEPTOR INC. CONTRACTIBILITY OF THE HEART
BLOOD VESSELS
DEC. BP (REDUCED NOREPINEPHRINE)
SMOOTH MUSCLES GI TRACT
DEC. GI TONE AND MOTILITY
BETA 1 RECEPTOR
HEART
KIDNEY
INC. HEART CONTRACTION
INC. RENIN SECRETION
INC. HEART RATE
INC. ANGIOTEN SIN
INC BP
BETA 2 RECEPTOR
SMOOTH MUSCLE GI TRACT
LUNGS
DEC. GI TONE AND MOTILITY
BRONCHODILATION
UTERUS
RELAXATION OF UTERINE SMOOTH MUSCLE
LIVER
ACTIVATION OF GLYCOGENOLY SIS
INC. BLOOD SUGAR
INACTIVATION OR NEUROTRAN SMITTER S -
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Caused by o
the transmitter back into the neuron (nerve terminal) Reuptake of
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Enzymatic transformation or degradation
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usion away from the receptor Diff
the enzymatic action MECHANISM OF NOREPINEPHRINE UPTAKE pla ys more important role in inactivation of