Exam 2 Pharmacology Study Guide Part two 48,49,54,55
c. What are the most important teaching points for patients receiving theophylline to treat obstructive pulmonary disorders?
* Bronchodilators work by relaxing the airways, helping to make breathing easier and to decrease wheezes and shortness of breath. To be effective, this drug must be taken exactly as prescribed. * This drug should be taken on an empty stomach with a full 8-oz glass of water. If GI upset is severe, you can take the drug with food. Do not chew the enteric-coated or time-release capsules or tablets—they must be swallowed whole to be effective. * Common effects of this drug include the following: o Gastrointestinal upset, nausea, vomiting, heartburn: Taking the drug with food may help this problem. o Restlessness, nervousness, difficulty sleeping: The body often adjusts to these effects over time. Avoiding other stimulants, such as caffeine, may help decrease some of these symptoms. o Headache: This often goes away with time. If headaches persist or become worse, notify your health care provider. o Report any of the following to your health care provider: vomiting, severe abdominal pain, pounding or fast heartbeat, confusion, unusual tiredness, muscle twitching, skin rash, and/or hives. * Many foods can change the way that your drug works; if you decide to change your diet, consult with your health care provider. * Adverse effects of the drug can be avoided by avoiding foods that contain caffeine or other xanthine derivatives (coffee, cola, chocolate, tea) or by using them in moderate amounts. This is especially important if you experience nervousness, restlessness, or sleeplessness. * Cigarette smoking affects the way your body uses this drug. If you decide to change your smoking habits, such as increasing or decreasing the number of cigarettes you smoke each day, consult with your health care provider regarding the possible need to adjust your dosage. * Avoid the use of any over-the-counter medication without first checking with your health care provider. Several of these medications can interfere with the effectiveness of this drug. * Tell any doctor, nurse, or other health care provider involved in your care that you are taking this drug. * Keep this drug, and all medications, out of the reach of children.
b. What are the therapeutic actions and most common adverse effects associated with decongestants?
* Decongestants are drugs that cause local vasoconstriction and, therefore, decrease the blood flow to the irritated and dilated capillaries of the mucous membranes lining the nasal passages and sinus cavities. * An adverse effect that accompanies frequent or prolonged use of decongestants is rebound vasodilation, called rhinitis medicamentosa. The reflex reaction to vasoconstriction is a rebound vasodilation, which often leads to prolonged overuse of decongestants. * Topical nasal decongestants are preferable in patients who need to avoid systemic adrenergic effects. Oral decongestants are associated with systemic adrenergic effects and require caution in patients with cardiovascular disease, hyperthyroidism, or diabetes mellitus. * Topical nasal steroid decongestants block the inflammatory response from occurring. These drugs, which take several days to weeks to reach complete effectiveness, are preferred for patients with allergic rhinitis who need to avoid the complications of systemic steroid therapy.
What are the indications and therapeutic actions for epoetin alfa, folic acid, and hydroxocobalamin?
* Epoetin Alfa o Indications: Treatment of anemia associated with chronic renal failure, related to treatment of HIV infection or to chemotherapy in cancer patients; to reduce the need for allogenic blood transfusions in surgical patients o Therapeutic actions: Natural glycoprotein that stimulates RBC production in the bone marrow * Folic Acid o Indications: Treatment of megaloblastic anemia due to sprue, nutritional deficiency o Therapeutic actions: Reduced form of folic acid, required for nucleoprotein synthesis and maintenance of normal erythropoiesis * Hydroxocobalamin o Indications: Treatment of vitamin B12 deficiency; to meet increased vitamin B12 requirements related to disease, pregnancy, or blood loss o Therapeutic actions: Essential for synthesis of nucleic acid and protein; used for growth, cell reproduction, hematopoiesis, and nucleoprotein and myelin synthesis
d. What are the indications, therapeutic actions, pharmacokinetics, and most common adverse effects associated with guaifenesin?
* Indications: Symptomatic relief of respiratory conditions characterized by dry, nonproductive cough and in the presence of mucus in the respiratory tract * Actions: Enhances the output of respiratory tract fluid by reducing the adhesiveness and surface tension of the fluid, facilitating the removal of viscous mucus * Pharmacokinetics: Route Onset Peak Duration Oral 30 min Unknown 4-6 h o T1/2: Unknown; metabolism and excretion are also unknown. * Adverse effects: Nausea, vomiting, headache, dizziness, rash
What are the important teaching points for patients receiving iron preparations used to treat anemias?
* Iron is a naturally occurring mineral found in many foods. It is used by the body to make red blood cells, which carry oxygen to all parts of the body. Supplemental iron needs to be taken when the body does not have enough iron available to make healthy red blood cells, a condition called anemia. * Iron is a toxic substance if too much is taken. You must avoid self-medicating with over-the-counter preparations containing iron while you are taking this drug. * You will need to return for regular medical checkups while taking this drug to determine its effectiveness. * Take your medication as follows, depending on the specific iron preparation that has been prescribed: o Dissolve ferrous salts in orange juice to improve the taste. o Take liquid iron preparations with a straw, to prevent the iron from staining the teeth. o Place iron drops on the back of the tongue to prevent staining the teeth. * Some of the following adverse effects may occur: o Dark, tarry, or green stools: The iron preparations stain the stools; the color remains as long as you are taking the drug and should not cause concern. o Constipation: This is a common problem; if it becomes too uncomfortable, consult with your health care provider for an appropriate remedy. o Nausea, indigestion, vomiting: This problem often can be solved by taking the drug with food, making sure to avoid eggs, milk, coffee and tea. o Report any of the following to your health care provider: severe diarrhea, severe abdominal pain or cramping, unusual tiredness or weakness, bluish tint to the lips or fingernail beds. * Tell any doctor, nurse, or other health care provider that you are taking this drug. * Keep this drug, and all medications, out of the reach of children. Because iron can be very toxic, seek emergency medical help immediately if you suspect that a child has taken this preparation unsupervised. * Because iron can interfere with the absorption of some drugs, do not take iron at the same time as tetracycline or antacids. These drugs must be taken during intervals when iron is not in the stomach.
. What information is important for the use of drugs that act on the upper respiratory tract with older adults?
* Older adults frequently are prescribed one of these drugs. Older adults are more likely to develop adverse effects associated with the use of these drugs, including sedation, confusion, and dizziness. Safety measures may be needed if these effects occur and interfere with the patient's mobility and balance. * Older adults are also more likely to have renal and/or hepatic impairment related to underlying medical conditions, which could interfere with the metabolism and excretion of these drugs. The dosage for older adults should be started at a lower level than recommended for younger adults. The patient should be monitored very closely, and dosage adjustment should be based on the patient's response. * These patients also need to be alerted to the potential for toxic effects when using OTC preparations and should be advised to check with their health care provider before beginning any OTC drug regimen.
b. What are the considerations for children for drugs used to treat anemias?
* Proper nutrition should be established for children to provide the essential elements needed for formation of RBCs. The cause of the anemia should be determined to avoid prolonged problems. * The safety and efficacy of epoetin alfa use have not been established for children. If the drug is used, careful dosage calculation should be done based on weight and age, and the child should be monitored very closely for response, iron levels, and nutrition. * Iron doses for replacement therapy are determined by age. If a liquid solution is being used, the child should drink it through a straw to avoid staining the teeth. Periodic blood counts should be performed; it may take 4 to 6 months of oral therapy to reverse an iron deficiency. Remember that iron can be toxic to children, and iron supplements should be kept out of their reach and administration monitored. * Maintenance doses for folic acid have been established for children based on age. Nutritional means should be used to establish folic acid levels whenever possible. * Children with pernicious anemia will require a monthly injection of vitamin B12; the nasal form has not been approved for use with children.
b. What are the therapeutic actions for sympathomimetics, leukotriene receptor antagonist
* Sympathomimetics are drugs that mimic the effects of the sympathetic nervous system. They are used for dilation of the bronchi and to increase rate and depth of respiration * Leukotriene receptor antagonists block or antagonize receptors for the production of leukotrienes D4 and E4, thus blocking many of the signs and symptoms of asthma.
a. What are the indications and therapeutic actions associated with antitussives?
Antitussive drugs suppress the cough reflex by acting centrally to suppress the medullary cough center of the brain to depress the cough reflexor locally as an anesthetic on the respiratory passages, lung or pleurae, blocking the effectiveness of the stretch receptors that stimulate a cough reflex or to increase secretion and buffer irritation.
What are the therapeutic actions and most common adverse reactions for aspirin, heparin, and urokinase?
Aspirin o Actions: Inhibits platelet aggregation by inhibiting platelet synthesis of thromboxane A2 o Adverse effects: Acute aspirin toxicity with hyperpnea, possibly leading to fever, coma, and cardiovascular collapse; nausea; dyspepsia; heartburn; epigastric discomfort; GI bleeding; occult blood loss; dizziness; tinnitus; difficulty hearing; anaphylactoid reaction * Heparin o Actions: Inhibits thrombus and clot production by blocking the conversion of prothrombin to thrombin and fibrinogen to fibrin o Adverse effects: Loss of hair, bruising, chills, fever, osteoporosis, suppression of renal function (with long-term use). * Urokinase o Actions: Converts endogenous plasminogen to plasmin, which breaks down fibrin clots, fibrinogen, and other plasma proteins; lyses thrombi and emboli o Adverse effects: Headache, angioneurotic edema, hypotension, skin rash, bleeding, breathing difficulties, bronchospasm, pain, fever, anaphylactic shock
What are the indications for mucolytics?
Mucolytics work to break down mucus in order to aid high-risk respiratory patients in coughing up thick, tenacious secretions.
What are the indications and therapeutic actions associated with antihistamines?
The antihistamines selectively block the effects of histamine at the histamine-1 receptor sites, decreasing the allergic response. Antihistamines are used for the relief of symptoms associated with seasonal and perennial allergic rhinitis, allergic conjunctivitis, uncomplicated urticaria, or angioedema. They are also used for the amelioration of allergic reactions to blood or blood products, for relief of discomfort associated with dermographism, andas adjunctive therapy in anaphylactic reactions. Patients taking antihistamines may react to dryness of the skin and mucous membranes.
a. What are the uses of drugs used to treat lower respiratory tract disorders:
sympathomimetics, anticholinergics, inhaled steroids * Sympathomimetics replicate the effects of the sympathetic nervous system; they dilate the bronchi and increase the rate and depth of respiration. * Anticholinergics affect the vagus nerve to relax bronchial smooth muscle and thereby promote bronchodilation. * Steroids decrease the inflammatory response. The inhalable form is associated with many fewer systemic effects than are the other corticosteroid formulations.
What is the process of erythropoiesis and its correlation with the development of three types of anemias?
· Red blood cells (RBCs) are produced in the bone marrow in a process called erythropoiesis, which is controlled by the glycoprotein erythropoietin, produced by the kidneys. · RBCs do not have a nucleus, and their lifespan is about 120 days, at which time they are lysed and their building blocks are recycled to make new RBCs. · The bone marrow uses iron, amino acids, carbohydrates, folic acid, and vitamin B12 to produce healthy, efficient RBCs. · An insufficient number or immaturity of RBCs results in low oxygen levels in the tissues, with tiredness, fatigue, and loss of reserve. · Anemia is a state of too few RBCs or ineffective RBCs. Anemia can be caused by a lack of erythropoietin or by a lack of the components needed to produce RBCs. · Iron deficiency anemia occurs when there is inadequate iron intake in the diet or an inability to absorb iron from the GI tract. Iron is needed to produce hemoglobin, which carries oxygen. Iron deficiency anemia is treated with iron replacement. · Iron is a very toxic mineral at high levels. The body controls the absorption of iron and carefully regulates its storage and movement in the body. · Folic acid and vitamin B12 are needed to produce a strong supporting structure in the RBC so that it can survive 120 days of being propelled through the vascular system. These are usually found in adequate amounts in the diet. Deficiencies are treated with folic acid and vitamin B12 replacement. · A dietary lack of or inability to absorb folic acid, vitamin B12, or both will produce a megaloblastic anemia, in which the RBCs are large and immature and have a short lifespan. · Pernicious anemia is a lack of vitamin B12, which is also used by the body to maintain the myelin sheath on nerve axons. If vitamin B12 is lacking, these neurons will degenerate and cause many CNS effects. · Pernicious anemia is caused by the deficient production of intrinsic factor by gastric cells. · Intrinsic factor is needed to allow the body to absorb vitamin B12. If intrinsic factor is lacking, vitamin B12 must be given parenterally or intranasally for life to ensure absorption. · Sickle cell anemia is a genetic disorder characterized by the production of hemoglobin S. The RBCs have a sickle shape and can stack up in blood vessels and cause anoxia, pain, and even cell death. · Sickle cell anemia is treated with antibiotics, pain-relieving measures, and the cytotoxic drug hydroxyurea, which causes increased fetal hemoglobin production in the bone marrow and dilution of the hemoglobin S with a resultant reduction in RBC stacking and clogging of blood vessels.