PHARMACY TECHNICIAN

PHARMACY TECHNICIAN CHAPTER TWENTY NINE

The Endocrine System • A “communication” system for the body • Major components of the endocrine system are: • Hypothalamus • Pituitary gland

The Endocrine System (cont.) • Secondary components of the endocrine system are: • Thyroid • Parathyroid • Pancreas • Adrenal glands • Gonads • The pituitary gland controls the secondary components of the endocrine system • During pregnancy, the placenta also acts as an endocrine gland

The Hypothalamus and Pituitary Gland • Hypothalamus • Part of the brainstem • Controls the activity of the pituitary gland • Pituitary gland • About the size of a large pea • Called the “master gland” because it controls many other glands • Composed of anterior and posterior lobes • Each lobe contains a number of hormones • Hormones—chemical substances that regulate certain bodily functions

Hormones • Transfer information and instructions from one set of cells to another • Each hormone affects only the cells that are genetically programmed to receive and respond to its message • Hormones are divided into two groups according to their structure: • Steroids—slow acting, long lasting, and usually end in the suffix “-rone” (examples: testosterone, progesterone) • Peptides and amines—made of proteins, fast acting, and short lived (examples: insulin, ADH)

Female Sex Hormones • Estrogen—responsible for: • Development of secondary sex characteristics • Formation of osteoblasts • Inhibition of osteoclasts • Bone loss • Progesterone—prepares lining of uterus for implantation of fertilized egg • Replacement female hormones may be derived from animal, plant, or lab-modified sources

Male Sex Hormones • Also called androgens or masculinizing hormones • Primary male sex hormone is testosterone: • Produced in the testes • Stimulates the development of male sex organs • Maintains secondary sex characteristics • Progesterone—maintains healthy prostate • Replacement male hormones are typically anabolic steroids

Glandular Disease States • Some cancers (breast, uterus, prostate gland) are dependent on sex hormones • Use of opposite sex hormones appears to antagonize or inhibit tumor growth • Endocrine therapy is palliative only

Pituitary Gigantism • Results from an excessive secretion of GH in childhood • Usually caused by a nonmalignant tumor of the pituitary gland • Causes the child to grow excessively and to be bigger in all areas of the body • Size and growth are proportionate

Pituitary Dwarfism • Results from a lack of GH • Person may be somewhat short at birth • In most cases the child’s growth is normal until 6 to 12 months of age

Acromegaly • Excessive secretion of GH during the adult years • Characterized by enlarged bones of the cheek, hands, feet, and jaws • Prominent forehead and large nose • Arms, legs, and hands are disproportionate, excessively large • Often the person will have slender arms, sometimes with atrophied muscles

Anabolic Steroid Use • Excessive steroid use signals the pituitary gland to stop producing gonadotropin • Natural ability to produce testosterone may shut down • May lead to a permanent imbalance of the hormone • In men and women, anabolic steroid use can lead to: • Edema and weight gain due to sodium and water retention • Jaundice or hepatic carcinoma • High cholesterol and associated diseases • Increased or decreased libido

Anabolic Steroid Use (cont.) • Women may undergo masculinization, such as growth of facial hair, permanent increases in amount of body hair, and permanent deepening of the voice • Men may endure sterility, impotence, priapism, and gynecomastia (enlarged breast and nipple tenderness)

PHARMACY TECHNICIAN CHAPTER THIRTY

Figure 30.1 The female reproductive system.

Female Reproductive System • Composed of internal organs and external genitals • Internal reproductive organs are: • Two ovaries • Two fallopian tubes • Uterus • Vagina • External genitals are known together as the vulva. The vulva consists of: • Labia minora • Labia majora • Clitoris

Male Reproductive System • Composed of external genitals and gonads, and internal organs • External genitals and gonads are the penis and testes • Internal organ is the prostate

Female Reproductive Function • The function of the female reproductive system is to conceive and bear children • Governed by the menstrual cycle, which consists of two stages: • Ovulation—prepares an oocyte for fertilization • Menstruation—dissolves the unfertilized oocyte and sheds uterine lining • Hormones that govern the female reproductive system are the estrogenic hormones • Estriol - Estrone - Estradiol

Male Reproductive Function • The function of the male reproductive system is to deliver sex cells to the female • Fertility in the male begins with the production of gonadotropin releasing hormone (GnRH) in the hypothalamus • GnRH instructs the pituitary gland to manufacture FSH and LH • FSH causes sperm production • LH stimulates production of testosterone

Infertility • Defined as the failure to conceive after one year of regular, unprotected intercourse • May be caused by either or both sex partners • In women, can be treated with antiestrogenic drugs • Stimulates pituitary production of FSH and LH • Boosts follicle growth and the release of eggs • In men, infertility can be treated with • Antibiotics—if infertility is caused by infection • Antihistamines—block mast cells that reduce sperm quality • Anti-erectile dysfunction agents—may enhance fertility by increasing sperm motion and capacitation

Infertility (cont.) • In men, infertility can be treated with • Bromocriptine—used to reduce excess prolactin manufactured by the pituitary • Gonadotropin releasing hormone (GnRH)—beneficial for men with gonadotropin deficiency and hypogonadism; good for restoring sperm production after chemotherapy

Pelvic Inflammatory Disease (PID) • The major cause of infertility worldwide • Symptoms of the reproductive system include: • Scarring • Abscess formation • Tubal damage • Treatment is with anti-infectives

Infertility From Sexually Transmitted Diseases • Affects both males and females • Viral STDs (genital herpes, HIV) • Symptoms managed with medication • Cannot be cured • Bacterial STDs (gonorrhea, chlamydia) • Curable with antibiotics • Fungal and parasitic diseases • Curable with antifungal and anthelminthic agents, respectively

Erectile Dysfunction • Inability to sustain an erection for penetration • Many causes, including stress and poor health • Treated with: • Levitra® (vardenafil) • Cialis® (tadalafil) • Viagra® (sildenafil)

Benign Orostatic Hyperplasia • Noncancerous growth or enlargement of the prostate gland • Treated with alpha-adrenergic blockers and 5-alpha reductase inhibitors • Alpha-adrenergic blockers relax smooth muscle tissue in the bladder neck and prostate, which increases urinary flow • 5-alpha reductase inhibitors prevent the conversion of testosterone to the hormone dihydrotestosterone (DHT

PHARMACY TECHNICIAN CHAPTER THIRTY ONE

The Nervous System • Divided into central nervous system (CNS) and peripheral nervous system (PNS) • Central nervous system • Includes brain and spinal cord • Controls all nervous system functions • Control may be direct or indirect • Peripheral nervous system • Includes all other nerves and sensory organs • Controlled by central nervous system • Divided into somatic and autonomic nervous systems

Functions of the Nervous System • Sensory (afferent) • Sends impulses from other parts of body toward the CNS • Senses external changes or conditions in the environment, such as cold or heat • Senses internal changes in the body, such as decrease in potassium or calcium • Integrative • Processes perceived information about the sensory changes • Interprets or explains changes in external/internal environments

Functions of the Nervous System (cont.) • Motor (efferent) • Sends impulses away from the CNS to other parts of the body • Allows and controls body movement • Causes glands to secrete hormones or other chemicals into the bloodstream

Sympathetic Nervous System • Governed by the neurotransmitter norepinephrine • Prepares body for energetic tasks, stressful situations, and the “fight or flight” response • Stimulates heart, lungs, and blood vessels • Decreases activity of gastrointestinal and genitourinary functions

Parasympathetic Nervous System • Governed by the neurotransmitter acetylcholine • Activates body for sleep in nonstressful periods • Effects the “rest and relaxation” response • Decreases activity of heart, lungs, and blood vessels • Increases activity of gastrointestinal and genitourinary functions

Neuron • Smallest unit of the nervous system • Brain is composed of approximately 100 billion neurons • Highly differentiated from other cells

Neuron (cont.) • Has specialized projections called dendrites and axons that communicate with the rest of the body: • Dendrites bring information to the cell body from the central nervous system • Axons take information away from the cell body to the central nervous system

Nervous System Communication • Neurons communicate with each other through an electrochemical process • Can be compared to a computer sending electrical signals over its wires • Brain sends electrical signals through neurons instead of wires • Neurons produce electrochemical hormones called neurotransmitters • Neurotransmitters are stored in the ends of the nerve cells

Neurotransmitters • Released at the end of the neuron • Synapse is the space between two different neurons • Neurons transfer information by crossing synapses • Neurotransmitters travel across the synapse to reach a receiving neuron • Attach to special structures called receptors • Communicate with and control glands, organs, and muscles

Blood-Brain Barrier (BBB) • Semipermeable membrane that allows some substances to enter brain, prevents others from entering • Protects brain from substances in the blood that could injure the brain and protects the brain from hormones and neurotransmitters in the rest of the body • Maintains a constant environment, or homeostasis, for the brain • Water-soluble or low-lipid/low-fat-soluble molecules do not penetrate and highly-lipid/fat-soluble molecules, such as barbiturates, rapidly cross • Large molecules do not easily pass through • Highly electrically charged molecules are slowed down

Anxiety • Uncomfortable emotional state characterized by apprehension, worry, and fear • Associated with the following risk factors: • Genetics • Brain chemistry • Life events • Personality • Treated with benzodiazepines, antidepressants

Depression • Symptoms include feelings of despair, lack of energy, inability to concentrate • Related to decreases in concentration of the neurotransmitters • Treated with drugs that: • Block the reuptake of neurotransmitters • Interfere with the breakdown of the monoamines within the synaptic cleft

Bipolar Disorder • Characterized by severe emotional highs (mania) and lows (depression) • Episodes, referred to as mood swings, can last hours, days, months, or years • Treatment may include: • Lithium—reduces hyperexcitability of the nerves • Antidepressant drugs

Psychosis • State in which a person is out of touch with reality • One cause may be an increase in dopamine • Treated with antipsychotic drugs that attach to the dopamine D2 receptor

Mental Disorders • The following mental disorders may be treated psychotherapeutically: • Psychosis • Depression • Anxiety • Obsessive-compulsive disorder • Panic disorder • Although there is no cure for mental illness, drugs will help the patient to have a better experience in daily living and function more effectively

Mental Disorders (cont.) • The National Institutes of Mental Health classifies the following four types of psychotherapeutic agents: • Antianxiety • Antidepressant • Antimanic • Antipsychotic

PHARMACY TECHNICIAN CHAPTER THIRTY TWO

Age Categories • Neonates are newborn babies, from birth to one month of age • Infants are between the ages of one month to two years • A child or “pediatric” patient is considered to be between 2 years and 12 years of age

Pharmacokinetics • Significant physiologic differences with pediatric patients • Absorption, distribution, metabolism, and excretion occur differently in children • Organ systems are not fully developed • Pediatric patients may not absorb a medication as quickly as adults • Children have more water and less fat in their bodies • Water-soluble and fat-soluble drugs will not distribute in the same manner • Children may have slower or more rapid metabolism rates • Children may have slower excretion rates than adults, leading to toxicity risks

Administering Medications • Dosage adjustments must be considered to compensate for physiological differences • Route of administration and dosage forms must also be considered • Compliance in pediatric patients is an important factor • Liquids are the dosage form most commonly used, because they can be colored and flavored to mask bitter or other unpleasant tastes

Determining Dose • Several formulas are used, including those based on: • Weight • Age • Body surface area (BSA) • Milligrams per body weight per day • Body weight is most common and reliable method used • Age is considered the least reliable

Asthma • Affects around 6 million children under the age of 18 each year in the United States • The most common chronic condition among children • Accounts for several million absences from school each year

Jaundice • Affects as many as 50 percent of newborns in the first two to four days postpartum • Typically disappears by one to two weeks of life • Causes skin and whites of the eyes to appear yellow • Caused by excess buildup of bilirubin in the blood • The infant’s liver cannot break down the bilirubin as fast as the body makes it • If left untreated, high levels can cause deafness, cerebral palsy, and brain damage

PHARMACY TECHNICIAN CHAPTER THIRTY THREE

PHARMACY TECHNICIAN