... Show The first statement is true; the second statement is false. -The first statement is true; the second statement is false. Nystatin is available for treatment of oral candidiasis in the form of an aqueous suspension and oral pastilles. The aqueous solution should be used as a rinse and expectorated, although swallowing is unlikely to result in harm because the gastrointestinal tract does not absorb the drug. Clarithromycin Clarithromycin Which statement is correct regarding the Opioid Hydromorphone (Dilaudid)? It is reserved for management of severe pain. It is favored by addicts because of its strength. -Hydromorphone (Dilaudid) is an orally effective opioid reserved for the management of severe pain. It is more potent than morphine and better absorbed orally but produces similar adverse reactions. Addicts like to use it because of its strength Which route of administration will REDUCE the systemic distribution of opioids? Oral. Opioids should be used w/caution w/other CNS depressants. The respiratory depression produced by the opioids is additive w/that produced by other CNS depressants. Both statements are TRUE. Which routes of absorption can be used w/opioids? Oral, Parenteral, Transdermal Patches absorbed through the Mucous Membranes of the Mouth, Nose & Lungs. -Most opioid analgesic agents are absorbed well when taken orally; absorption occurs from the lungs and from the nasal and oral mucosa and from intact skin through transdermal patches. They are also administered parenterally. Intramuscular administration is rare Which factors determines the addition potential of opioids? Potency of the analgesic & frequency of use. -The degree of addiction potential of opioids is proportional to their analgesic strength and duration and their frequency of use, limiting the usefulness of the strongest agents. Opioids that produce euphoria and reduce anxiety have a stronger addiction potential than opioids that do not produce euphoria and reduce anxiety. All of the statements are TRUE regarding codeine EXCEPT which of the following? Codeine is so effective that it is the drug of choice for dental inflammatory pain. -Although codeine is the most commonly used opioid used in dentistry when combined with acetaminophen, it is a relatively weak analgesic. Codeine taken alone is no more efficacious than two tablets of aspirin or acetaminophen, with prescription doses of NSAIDs producing better pain management for dentistry. When codeine is combined with nonopioid analgesics, there is additive analgesic effect, so combinations of codeine with aspirin or acetaminophen are available. Adverse effects include nausea, vomiting, dizziness, and physical dependence. Large doses of the opioids have which effects on the Cardiovascular System? Postural Hypotension, Syncope; Stimulation of Vagus nerve; Bradychardia. -In large doses, opioids may depress the vasomotor center, simulating the vagus nerve. Postural hypotension, bradycardia, and even syncope may result. Depression of the vagus nerve does not occur when large doses of the opioids are administered. Pts who are given analgesic doses of opioids frequently suffer from Nausea & Vomiting caused by the stimulation of the chemoreceptor trigger zone in the brain. How can this adverse effect be REDUCED? By taking the medication w/a meal & by discouraging movement or ambulation. -Movement will stimulate the chemoreceptor trigger zone in the brain and will increase the likelihood of nausea and vomiting; having the patient remain quiet will reduce these effects. Taking the medication with a full glass of water and a meal will also reduce gastrointestinal upset. The opioids are linked to Hepatic, Renal & Hematologic tissue damage. The adverse effects of the opioids are extensions of their pharmacologic effects, which if proportional to their analgesic strength. The 1st statement is FALSE, the 2nd statement is TRUE. -The first statement is false; the second statement is true. The opioids are unique in that they do not directly damage the liver, kidneys, and other tissues. Their adverse effects are extensions of their pharmacologic effect; the stronger the agent is, the more adverse effects will occur, such as depression of the central nervous system, causing coma or death in large doses of morphine. What is the usual cause of death in opioid overdose? Respiratory Depression. -The opioid analgesic agonists depress the respiratory center of the brain in relation to the dose. Rate and depth of respiration are reduced, and the usual cause of death in opioid overdose is respiratory arrest. Unlike many medications, opioids do not directly damage the kidneys, liver, or hematologic tissue. Opioid overdose would lead to hypotension, not hypertension, but hypotension is not the usual cause of death in these cases. Why would a pt. who is taking opioids develop a runny nose & itchy eyes? Histamine release stimulated by opioids. -Opioids can stimulate the release of histamine, and itching and urticaria can result from their administration. This effect can occur at the site of intramuscular injection or at remote sites (e.g., itchy nose). The most common type of allergic reactions to opioids are dermatologic and include skin rashes and urticaria. Contact dermatitis may occur with topical exposure. It is important to differentiate between allergy and adverse drug effects. Opioid analgesics do not directly affect capillary vasoconstriction or bronchoconstriction. Pts. w/which condition are least sensitive to the respiratory depression induced by opioids? Hyperthyroidism. -Patients with hyperthyroidism are more tolerant to opioid agonist-induced respiratory depression, whereas patients with hypothyroidism are more sensitive to respiratory depression. Opioids should not be used in patients with head injuries because the opioids could mask central nervous system diagnostic symptoms. Diabetes has no direct effect on opioid agonist-induced respiratory depression. Opioid abuse/overdose can often be diagnosed by which sign? Myosis (pinpoint pupils) -Opioid abuse or overdose causes the pupils to constrict, and tolerance to miosis does not develop. Mydriasis, or dilation of the pupils, may occur with amphetamine use. Photophobia and CNS excitation are not commonly associated with opioid abuse or overdose. How much codeine is added to acetaminophen for the prescription medication Tylenol #3? 30 mg. -The amount of codeine in combination products is designated by Arabic numbers: #2 = 15 mg of codeine, #3 = 30 mg of codeine, and #4 = 60 mg of codeine. Doses greater than 30 to 60 mg usually produce too much nausea for the patient to tolerate well. Nausea & Vomiting w/analgesic doses of opioids is caused by which of the following? Direct stimulation of chemoreceptor trigger zone in the Medulla & pt. movement. -The nausea and vomiting often experienced in analgesic doses of opioids is caused by their direct stimulation of the chemoreceptor trigger zone in the medulla of the brain. Movement by the patient will make the nausea worse; therefore, patients should be discouraged from being ambulatory when they are taking these medications. Indirect stimulation of the vestibulocochlear area is not involved in opioid-induced nausea and vomiting.
Which opioid family is most commonly used perioperatively or during general anesthesia? Fetanyl Family. -Fentanyl (Duragesic, Sublimaze), sufentanil (Sufenta), and alfentanil (Alfenta) are short-acting parenterally administered agonist opioid analgesics that are used perioperatively or during general anesthesia. Morphine is used parenterally to control postoperative pain in hospitalized patients. Methadone is used primarily for treatment of opioid addiction. Oxycodone is used alone or combined with aspirin in Percodan, or acetaminophen in Percocet and Tylox for relief of moderate to severe pain. All are pharmacologic actions of opioids EXCEPT which of the following? Excitation. -Central nervous system excitation rarely occurs, because opioids are considered central nervous system depressors. In usual therapeutic doses, opioids produce analgesia, sedation and euphoria, relief from anxiety, cough suppression, and peristaltic action reduction. Naloxone (Narcon) is an example of a(m): Opioid Antagonist. -Naloxone (Narcan) is a pure opioid antagonist and can be used to treat an opioid overdose by binding to the opioid receptor site and blocking the action of the opioid. An opioid agonist will bind to the opioid receptors and produce the drug effect. Morphine is the prototype opioid agonist. A partial opioid agonist (buprenorphine) may suppress or precipitate withdrawal in an opioid-dependant person, depending on the amount of opioid in the patient's bloodstream. The only oral opioid agonist-antagonist, pentazocine (Talwin), produces analgesia, sedation, and respiratory depression, but the analgesia is due to stimulation of different receptors than the opioid agonists. All of these terms refer to analgesic drugs that affect the CNS EXCEPT which of the following? Nonsteroidal Antinflammatory drug (NSAIDs). -NSAIDs are nonopioid analgesics. Opioids, opiates, and narcotics are terms used to identify analgesics with the ability to depress the central nervous system. Opioids mimic the action of which endogenous substances by binding to these naturally occurring receptor sites? Enkephalins, Endorphins & Dynorphins. -The enkephalins, endorphins, and dynorphins are three groups of endogenous substances that produce an opioid-like action in the body by binding to naturally occurring receptor sites. These naturally occurring peptides have analgesic action and have an addiction potential. Opioid withdrawal includes all signs & symptoms EXCEPT which of the following? Drowsiness. -Drowsiness is not a symptom of opioid withdrawal. Persons withdrawing from opioids suffer from irritability, piloerection ("goose bumps"), nausea and vomiting, tachycardia, tremors and chills, agitation, along with yawning, lacrimation, perspiration, and rhinorrhea. Ms. Jones, in her 37th week of pregnancy, is being treated at a methadone clinic for her heroin addiction. If she goes into labor and her baby is born, which effect would her opioid use have on her baby? Fetal respiratory depression & withdrawal symptoms. -Her baby could be born with fetal respiratory depression and symptoms of withdrawal. Opioids are well distributed to the fetus in pregnant women, and respiratory depression can be produced if opioids are taken near term. Teratogenic effects and fetal malformation are not associated with opioid use in pregnancy. Fetal tachycardia and cardiovascular distress are not associated with opioid use in pregnancy. Premature closure of the ductus arterious can occur in pregnant women taking aspirin or nonsteroidal antiinflammatory drugs (NSAIDs) near term. Which opioid is considered the prototype (ex: drug against which all other opioids are measured)? Morphine. -Morphine is the drug against which other opioids are measured. Opioid analgesics vary in their analgesic ability, with morphine having high efficacy and codeine being a relatively weak analgesic. Tramadol (Ultra) is classified as a pure opioid agonist that binds w/the k-receptor & the b-receptor. Both statements are FALSE. -Both statements are false. Tramadol (Ultra) is unique in its classification as an analgesic. It has an opioid agonist action but also inhibits the reuptake of norepinephrine and serotonin, modifying the ascending pain pathways. It has some, but not all, of the properties of an opioid because it does not affect the κ receptor and the δ receptors, but it binds with the μ receptor. Codeine has all effects in usual therapeutic doses EXCEPT which of the following? CNS excitation. -Codeine rarely causes central nervous system excitation. In usual therapeutic doses, codeine has analgesic, sedative, antitussive, and antidiarrheal effects. What is the most commonly used opioid in dentistry? Codeine. -Codeine in combination with nonopioid analgesics such as acetaminophen, aspirin, and ibuprofen is the most commonly used opioid in dentistry. Codeine combinations are schedule III drugs, with less potential for abuse and addiction than oxycodone, hydrocodone, or hydromorphone, which are schedule II drugs. Tramadol (Ultram) is not a commonly prescribed opioid in dentistry and is associated with physical dependency and withdrawal symptoms. One method of classifying is by their mechanism of action @ the receptor sites. Agents that act on the same receptor sites are most likely to be cross-allergenic. The 1st statement is TRUE, the 2nd statement is FALSE. -The first statement is true; the second statement is false. One method of classifying opioids is by their mechanism of action at the receptor sites, as agonists, mixed opioids, and antagonists. The second statement is false because cross-allergenicity is more likely to occur in drugs with a similar chemical structure. Muperidine (Demerol) is a good choice for oral use bc it has a long duration of action & few drug interactions. Both statements are FALSE. -Both statements are false. Meperidine (Demerol) has a rapid onset but a short duration of action. There are drug interactions among meperidine and Monoamine oxidase inhibitors (MAOIs) and phenothiazines, making it a poor choice for controlling oral pain. What is the major route of metabolism for the opioids? Liver. -The major route of metabolism for the opioids is conjugation with glucuronic acid in the liver. The kidneys are the primary sites of excretion. The lungs and blood plasma is not the major route of metabolism for the opioids. "Shoppers" are addicts who try to use dentists or physicians who will prescribe their drug of choice. Shoppers are usually willing to try any opioid or controlled substance the physician is willing to provide. The 1st statement is TRUE, the 2nst statements I FALSE. -The first statement is true; the second statement is false. "Shoppers" are addicts who try to use dentists or physicians who will prescribe their drug of choice. Shoppers are usually specific about the drug they want, and they may claim allergies or lack of effectiveness of medications that the physician wishes to prescribe. Tolerance does not develop to which effects of opioids? Miosis & Constipation. -Tolerance does not develop to miosis (pupil constriction) or to constipation, even with long-term opioid use. Persons who repeatedly use opioids will develop tolerance to the sedative and euphoric effects of opioids, to cough suppression, and to nausea and vomiting. Naloxine (Narcan) is an opioid antagonist that is active parenterally. If given to an addict who has overdosed, large dose must be administered to counteract the opioid-induced respiratory depression. The 1st statement is TRUE, the 2nd statements is FALSE. -The first statement is true; the second statement is false. Naloxone will reverse opioid-induced respiratory depression. However, small doses must be carefully titrated or opioid withdrawal may be produced. Which opioid is frequently used to help pts. discontinue opioid use and it used BOTH short term & long term for maintenance? Methadone. -Methadone is an opioid that is used to help patients discontinue opioid use. If given for the short term, oral methadone substitutes for the injectable opioid and may be given long term for methadone maintenance. Within methadone maintenance, the patient takes supervised large oral doses of methadone on a daily basis. Because the patient develops a tolerance for the effects of the opioids, a block is produced that prevents heroin-like agents from producing the "rush" feeling after injecting. The rate of development of tolerance and addiction is related to the strength of the opioid & its frequency & lengths of use. Addiction to opioid analgesics is a common problem when they are used to treat dental-related pain. The 1st statement is TRUE, the 2nd statement is FALSE. -The first statement is true; the second statement is false. The degree of tolerance and addiction potential of opioids is proportional to their analgesic strength and frequency and duration of use. Because the duration of use in dentistry is usually short, addiction or tolerance is not usually a problem. Differences in action of different opioids intolerance to pain may be the result of variations in the endogenous levels of the neurotransmitters. Differences in the action of different opioids at theses & other specific receptors explain some of the variations among the different opioids adverse reactions. Both statements are TRUE. Which statements are correct concerning depression of the respiratory center by opioids? Respiratory depression is Dose-Related. -Opioid analgesic agonists depress the respiratory center in the brainstem related to dosage. Opioid agonists decrease the sensitivity of the brainstem to carbon dioxide and decrease the rate and depth of breathing. In elderly adults or debilitated persons, the usual therapeutic dose can cause significant reductions in pulmonary ventilation. The usual cause of death in opioid overdose is respiratory depression and is therefore a major concern with the use of these drugs. Small doses of even weak opioids often cause constipation, with continued administration, tolerance will develop to this effect. The 1st statement is TRUE, the 2nd statement is FALSE. -The first statement is true; the second statement is false. Small doses of even weak opioids often cause constipation. The duration of constipation with opioids outlasts their analgesic effect, and even with continued administration, tolerance does not develop to this effect. Methadone (Dolophine) has all of these advantages over Morphine or Hydrocodone EXCEPT which of the following? Great risk for death & life-threatening changes in respiration & heart rate. -Methadone is now being used as an analgesic, as well as a maintenance drug for heroin withdrawal, and it has several advantages such as longer duration of action, good bioavailability, oral administration, and easier withdrawal than morphine and hydrocodone. However, only low doses should be prescribed for pain because life-threatening changes in respiration and heart rate and death have occurred with its use. 12. What is the largest group of opioids? Opioid agonists -Opioid agonists are the largest group of opioids. This group includes morphine, oxycodone, oxymorphone, hydrocodone, codeine, meperidine, hydromorphone, methadone, and fentanyl. The only partial opioid agonist is buprenorphine. The only oral opioid agonist-antagonist is pentazocine (Talwin). Opioid antagonists include naloxone (Narcan), nalmefene (Revex), and naltrexone (ReVia, Vivitrol). Which statements are correct concerning opioid receptors? Stimulation of μ-receptors produces analgesia. The κ-receptor is responsible for dysphoria. Naloxone is an antagonist at the three receptor sites. Morphine has no effect on the κ-receptor. -All of the statements are true, leading to different reactions, depending on the receptor stimulated and the specific drug used. 23. The patient states that he is allergic to morphine. Which other opioid would be safe to administer to this patient? Pentazocine -Morphine, oxycodone, hydrocodone, codeine, and hydromorphone are all opioid agonists, with a similar mechanism of action, which increases the chance of a cross-reactivity or allergic reaction with any of these drugs. Pentazocine (Talwin) is an agonist-antagonist opioid with a different mechanism of action, which decreases the likelihood of a cross-reaction. Chapter:AntiinfectiveAgents ... Please list the correct evolution of dental infections.(1) Gram-positive infection begins to include a variety of both gram-positive and gram-negative anaerobic microorganisms (mixed infection).(2) The infection consists of predominantly anaerobic microorganisms.(3) The anaerobic microorganisms coalesce into an abscess.(4) The organisms responsible for the dental infection are primarily gram-positive cocci. 4, 1, 2, 3 -Dental infections start as primarily gram-positive cocci and rods and, if left undisturbed, grow in mass and complexity to include both gram-positive and gram-anaerobic microorganisms, becoming a mixed infection. The proportion of gram-anaerobic microorganisms increases as time passes, and they will eventually coalesce into an abscess. The ability of an antiinfective agent to slow or stop the growth of an organism is tested by use of a(n) Culture & Sensitivity testing -The most effective treatment of infections would require that the organism be cultured and sensitivity tests would be performed. Culturing involves growing the bacteria from a sample of infective exudate, and sensitivity testing involves exposing the organism to certain test antibiotics and determining whether the organism is sensitive or resistant. An antibody assay is a test to determine if the body has produced antibodies in response to exposure to a specific antigen. Minimum inhibitory concentration (MIC) is the lowest concentration of an antimicrobial agent that inhibits the visible growth of a microorganism after overnight incubation. What is the current American Heart Association prophylactic premedication dosage for the prevention of infective endocarditis in the patient who can take penicillin? 2 gram amoxicillin taken 30 to 60 minutes before treatment -Two grams of amoxicillin, given 30 to 60 minutes before treatment, is the drug of choice for prophylaxis of infective endocarditis before a dental procedure in a patient who is not allergic to penicillin. Penicillin was formerly the drug of choice for prophylaxis of infective endocarditis before a dental procedure; however, amoxicillin's better absorption, higher plasma levels, and slightly broader spectrum of action have replaced penicillin in this role. Ampicillin, given parentally can be administered for the prevention of infective endocarditis in the patient who can take penicillin but is unable to take medication orally. Two grams cephalosporin may be taken 30 to 60 minutes before treatment in the patient who has a penicillin allergy, as long as the allergy did not produce severe adverse effects such as angioedema or anaphylaxis. The terms antibiotic, antiinfective, antimicrobial, and antibacterial are often used interchangeably. However, only an __ is exclusively produced by microorganisms. Antibiotic -By definition, only antibiotics are produced exclusively by microorganisms, whereas the other agents may be produced in a laboratory from nonliving sources. Penicillin, cephalosporin, and tetracyclines are true antibiotic agents. Antiinfective agents are substances that act against or destroy infections. An antibacterial substance destroys or suppresses the growth or multiplication of bacteria, and an antimicrobial agent is a substance that destroys or suppresses the growth of microorganisms A culture is a test that involves determining if an organism will respond to a specific antiinfective agent. Sensitivity testing involves growing the bacteria from a sample of infective exudate. Both statements are false. -Both statements are false. A culture is a test that involves growing the bacteria from a sample of infective exudate. Sensitivity testing involves exposing an organism to test antiinfective agents to determine if the organism is sensitive or resistant to a specific antiinfective agent. Mr. Garza indicates on his medical history that he is taking isoniazid, pyrazinamide, and rifampin. What is the most likely reason he is taking these medicines? Tuberculosis -Tuberculosis (TB) is difficult to treat due to the ability of the tubercle bacilli to develop resistant strains easily, the bacteriostatic nature of the medications, and lack of appropriate medication compliance. Because of the danger of resistance, at least three drugs are used in combination concurrently in treatment of active tuberculosis. Isoniazid (INH), rifampin, ethambutol, and pyrazinamide are combined for treatment of pulmonary TB. INH and rifampin are given every day for 9 to 12 months. Pyrazinamide and ethambutol are used only in the first two months of treatment. Which drug or drugs are used most often in dentistry for beginning infections of primarily gram-positive cocci in patients with no allergies? Penicillin/amoxicillin -In early infections consisting of gram-positive cocci, penicillin is the drug of choice, unless the patient has a penicillin allergy. Amoxicillin is most often used because it is less irritating to the stomach and can be taken with food or milk. Erythromycin or azithromycin would be indicated if the patient were allergic to penicillin. Metronidazole is used in combination with other medications for treatment of later infections with anaerobic microorganisms. Which class of antibiotics is structurally related to the penicillins and has similar mechanisms of actions and indications as the penicillins? Cephalosporins -The bactericidal cephalosporins are a group of antibiotics that are structurally related to the penicillins. Their mechanism of action is also inhibition of cell wall synthesis, and they have a similar spectrum of bacterial activity. They have a lower incidence of allergic reactions than the penicillins. Which situations would be an indication for use of an antiinfective agent? Localized dental infections in an immunocompromised patient & Systemic dental infections with fever, malaise, and tachycardia in which drainage is unable to accomplished -Lesions associated with systemic dental infections with symptoms such as fever, malaise, and tachycardia should be drained. However, if drainage is not possible, antibiotics should be given. If adequate drainage can be obtained, antiinfective agents are not indicated for most localized dental infections unless the patient is immunocompromised. The penicillins can be divided into all except which of the following major groups? Cephalosporin -The cephalosporins are closely related to the penicillins but are not in the penicillin family. Penicillin G and V, the penicillinase-resistant penicillins, amoxicillin/ampicillin, and the extended-spectrum penicillins are major groups of the penicillin family. All are classified macrolides drugs except which of the following? Minocycline -Minocycline is a member of the tetracycline family; erythromycin, clarithromycin, and azithromycin are macrolides antiinfective agents. All of these antibiotics are typically administered topically except which of the following? Clarithromycin -Clarithromycin is a macrolide and is usually administered by mouth. Neomycin is combined with polymyxin and bacitracin in the topical ointment form Neosporin. Mupirocin (Bactroban) is a topical antibiotic that may be used to treat the streptococci or staphylococci that may be present with angular chilitis. All are common adverse effects of antiinfectives except which of the following? Central nervous system depression -Central nervous system depression is not a common adverse effect of antiinfective agents. Gastrointestinal upset, a decrease in the effectiveness of oral contraceptives, superinfection with Candida albicans, potentiation of oral anticoagulants, and potential to produce allergic reactions are all adverse drug effects seen in some degree with antiinfective agents. All statements are correct concerning antiinfective agents and localized dental infections except which of the following? Even if adequate drainage can be obtained, antiinfective agents are indicated. -If adequate drainage of a can be obtained, antiinfective agents are not indicated for most localized dental infections unless the patient is immunocompromised, because the body has been able to contain the infection to a small area, and drainage of the area will assist systemic defenses in overcoming the infection. If the patient is immunocompromised, antiinfective agents may be indicated for localized dental infection. Most localized dental infections arise from either periodontic- or endodontic-related sources, and the microorganisms present determine the antibiotic of choice. Clindamycin is associated with the serious adverse drug effect of: Pseudomembranous colitis -Clindamycin is associated with the serious adverse drug effect of pseudomembranous colitis (PMC), also known as antibiotic-associated colitis. PMC is characterized by severe, persistent, bloody diarrhea, and it can be fatal. Its etiology is the toxin produced by the bacterium Clostridium difficile and is associated with all antibiotics, not only clindamycin. Photosensitivity is an adverse drug effect associated with tetracycline. A disulfiram-like reaction is an adverse drug effect associated with the drug interaction between metronidazole and alcohol, which can produce nausea, vomiting, abdominal cramps, and headache. Hepatoxicity is an adverse drug effect associated with the intravenous (IV) use of tetracyclines. __ is the antiinfective drug of choice for prophylactic premedication for a patient with artificial heart valves if the patient is not allergic to penicillin. Amoxicillin -Amoxicillin is the drug of choice for prophylaxis of bacterial endocarditis before a dental procedure in the patient who is not allergic to penicillin. Penicillin VK was originally the drug of choice for this indication, but the slightly broader antimicrobial spectrum and fewer gastrointestinal adverse effects of amoxicillin have resulted in its substitution for penicillin VK. Erythromycin was formerly the drug of choice prophylaxis of bacterial endocarditis before a dental procedure in the patient who is not allergic to penicillin; however, it has been replaced by clindamycin due to the severe gastrointestinal adverse effects of erythromycin. Clindamycin is the drug of choice for prophylaxis of bacterial endocarditis before a dental procedure in the patient who is allergic to penicillin. Which group of antiinfectives is most likely to cause gastrointestinal upset? Erythromycin -Erythromycin has the highest incidence of gastrointestinal complaints of any of the antibiotics, although some degree of gastrointestinal upset is common with all of the antiinfectives. Caries is an important dental infection produced by Streptococcus mutans. Traditional antiinfective agents have been useful for this problem in the general population. The first statement is true; the second statement is false. -The first statement is true; the second statement is false. Caries is an important communicable dental infection, but traditional antiinfective agents have not been effective in treating caries. This is largely due to the constant presence of bacterial biofilm that is the etiologic agent of caries, and the location of caries, which is in a nonvascular structure, the enamel. The treatment of choice is ingestion of appropriately fluoridated water, regular physical disruption of bacterial biofilm, a diet low in refined carbohydrates, regular preventive dental visits, and appropriately placed sealants. What antiinfective agent is most likely to produce an allergic reaction? Penicillin -Penicillin is the most common cause of drug allergies. All antiinfective agents, like all medications, have the potential to produce a variety of allergic reactions, from mild to life threatening. Ciprofloxacin is bacteriostatic against a wide range of gram-positive organisms. A synergistic action may occur if ciprofloxacin is given with other antimicrobial agents. Both statements are false. -Both statements are false. Ciprofloxacin is bactericidal against a wide range of gram-negative organisms. An additive action may occur if ciprofloxacin is given with other antimicrobial agents. Ciprofloxacin is indicated for infections of the lower respiratory tract, skin, bone and joint, and urinary tract infections. Antibiotic resistance is the natural or acquired ability of an organism to be immune to or to resist the effects of an antiinfective agent. An increase in the use of an antibiotic in a given population decreases the proportion of resistant organisms in that population. The first statement is true; the second statement is false. -The first statement is true; the second statement is false. An increase in the use of an antibiotic in a given population increases the proportion of resistant organisms in that population. Which is the mechanism of action of the sulfonamide drug group? Competitive inhibition of folic acid synthesis from paraaminobenzoic acid -Sulfonamides, or "sulfa drugs," competitively inhibit the bacterial enzyme that converts paraaminobenzoic acid into folic acid. Bacteria are unable to synthesize folic acid for their growth; therefore, by inhibiting its synthesis, sulfonamides have a bacteriostatic action. Sulfonamides are used to treat otitis media, bronchitis, and urinary tract infections but are not commonly used to treat dental infections. Which adverse drug interactions could occur with antiinfectives? Some antibiotics may decrease oral contraceptive efficacy. Antiinfective agents can increase the effect of oral anticoagulants. Bacteriostatic agents may interfere with bactericidal agents. -Some antibiotics may decrease oral contraceptive efficacy by increasing their clearance from the body. Antiinfective agents may reduce the bacterial flora that produce vitamin K. Vitamin K is needed to for adequate blood clotting, so reduction may result in an increased effect of oral anticoagulant. Bacteriostatic agents may interfere with bactericidal agents. Broad-spectrum antiinfective agents taken over a long time period can lead to which adverse reactions? Superinfection/suprainfection -Broad-spectrum antibiotics taken for a long period can disturb the normal microflora of the body, allowing the emergence of organisms different from the original infecting organism and that are unaffected by or resistant to the antibiotic being used. This situation is termed a superinfection or suprainfection. Tolerance is a condition in which the patient no longer responds to the drug, and larger amounts of the drug are needed to produce the desired effect. Tolerance does not occur with antibiotics. Allergic reactions are not related to length of time a drug is taken; they can occur within minutes of the drug administration. Antibiotics do not produce dependence, or the physiologic or psychological need for a drug. ... ... Which antiinfective drug is contraindicated in a pregnant patient? etracycline -Tetracycline is contraindicated in pregnancy because of its staining effect on developing teeth. Tetracycline is rated as a Food and Drug Administration category D pregnancy drug. Amoxicillin, erythromycin, and penicillin VK are classified by the Food and Drug Administration as category B drugs, which are considered safe, due to lack of evidence of teratogenicity, although there are no controlled data on human pregnancy. Use of any medication should always weigh benefits against risks. All factors must be present for a microorganism to cause an infection except which of the following? Exposure to cold and damp weather Which statement about erythromycin is incorrect? Allergic reactions are common with erythromycin. -Allergic reactions to erythromycin are uncommon, making erythromycin the drug of choice against aerobic microorganisms in penicillin-allergic patients. Erythromycin is bacteriostatic and interferes with protein synthesis, and the spectrum of action closely resembles that of penicillin against gram-positive bacteria. Adverse effects include severe gastrointestinal distress. Erythromycin can increase the serum concentrations of many drugs through inhibition of the hepatic metabolism of these drugs. All are adverse effects that can occur with use of tetracycline except which of the following? Permanent discoloration of teeth if taken after development Which antiinfective agent has reduced effectiveness if taken with dairy products, antacids, or calcium supplements? Tetracycline Chapter 8: Antiviral & Antifungal
... All are medications indicated for the treatment of oral herpes simplex except which of the following? Zidovudine -Zidovudine (AZT, Retrovir) is a thymidine analogue and is used to treat human immunodeficiency virus by inhibiting synthesis of the virus. Acyclovir, penciclovir (Denavir), famciclovir, and valacyclovir (Valtrex) are prescription medications used to treat herpes viruses. Docosanol (Abreva) is an over-the-counter medication used to treat herpes simplex. Which special considerations should be made for patients taking ketoconazole? Pregnant women should be advised not to take this medication. __ is used to treat oropharyngeal and esophageal candidiasis and serious systemic candida infection, and prophylactically in immunocompromised patients or for treatment of candida infections that do not respond to other agents. Fluconazole -Fluconazole is used to treat oropharyngeal and esophageal candidiasis and serious systemic candida infection, and prophylactically in immunocompromised patients or for treatment of candida infections that do not respond to other agents. Fluconazole can also be used to treat vaginal candidiasis. Which is the mechanism of action for the antiviral agent acyclovir? Nucleic acid analogues that inhibit deoxyribonucleic acid synthesis -Acyclovir is a purine analogue (nucleoside) that works by inhibiting deoxyribonucleic acid (DNA), not ribonucleic acid (RNA) synthesis. It is preferentially taken up by the infected cells, making it is less toxic to normal cells. Inhibition of cell wall synthesis is the action of bactericidal antibiotics. Increasing the permeability of the cell membrane is an action of some antibacterial and some antifungal agents. Inhibition of membrane permeability is not a mechanism of action of antimicrobial agents. The most frequent adverse drug effect of the imidazoles involves which body system? Gastrointestinal system -The most common adverse reactions associated with the imidazole antifungal agents involve the gastrointestinal tract and include abdominal pain, diarrhea, and nausea. Antiviral agents work with a similar mechanism of action as antibacterial drugs because viruses are obligate intracellular organisms that require the host cell to be damaged to kill the virus. The first part of the statement is false; the second part is true. -The first part of the statement is false; the second part is true. Antiviral agents work entirely differently than antibacterial agents because viruses live within the host cell, and the host cell often must be destroyed to destroy the virus. Antibacterial drugs primarily damage the pathogenic microorganism by damaging the cell wall or interfering with protein synthesis. Interferons are better tolerated and have better virologic suppression than the oral nucleoside/nucleotide analogues in treatment of chronic hepatitis B. This is because the oral nucleoside/nucleotide analogues can only be taken for a very short period before toxicity develops. Both statements are false. -Both statements are false. The oral nucleoside/nucleotide analogues are better tolerated and have better virologic suppression in treatment of chronic hepatitis B than the interferons. Many patients are treated for at least 5 years, and some are treated indefinitely. Sudden discontinuation of the drug can lead to relapse and even death. What is the most common adverse reaction associated with the antifungal agent ketoconazole? Gastrointestinal distress, nausea, and vomiting -The most frequent adverse reactions (3% to 10%) associated with the antifungal agent ketoconazole are nausea and vomiting. These adverse reactions can be minimized by taking ketoconazole with food. The most serious adverse reaction is hepatoxicity, with an incidence of 1:10,000. Photophobia, skin rash and hives, and superinfection are less common adverse drug reactions to this medication. Candida albicans is a frequent inhabitant of the oral cavity, and it usually causes fungal infections. The first part of statement is true; the second part is false. -C. albicans is a frequent inhabitant of the oral cavity, but in the patient with a health immune system, healthy microflora keeps it in check. When patients become immunocompromised, the fungus is able to take advantage of the weakened host state and cause a fungal infection.
Which is the mechanism of action of nystatin? Increasing membrane permeability -Nystatin binds to the sterols in the fungal cell membrane, increasing membrane permeability and allowing leakage of potassium and other cellular constituents. This action is specific to fungal infections, because bacteria do not have sterols in their cell membranes and are not affected. Penicillins and cephalosporins have a bactericidal effect through inhibition of bacterial cell wall synthesis. The macrolides and tetracyclines inhibit bacterial ribosomal synthesis, with a bacteriostatic effect. No antimicrobial agents increase ribosomal synthesis or increase membrane permeability. Ketoconazole is indicated in the treatment and management of mucocutaneous and oropharyngeal candidiasis. Because of its lack of serious adverse reactions, systemic use of this drug is preferred to topical antifungal agents. The first statement is true; the second statement is false. -The first statement is true; the second statement is false. Ketoconazole is indicated for treatment and management of mucocutaneous and oropharyngeal candidiasis, and prophylactically for chronic mucocutaneous candidiasis. Because of serious adverse drug reactions, it should be used only after topical antifungal agents are ineffective.
Interferon alpha (α) has approval of the U.S. Food and Drug Administration (FDA) to treat which conditions? Hepatitis B & C -The FDA has approved interferon alfa for treatment of chronic hepatitis B and C. It has not been approved for treatment of hepatitis A or human immunodeficiency virus (HIV). The interferons are a large group of endogenous proteins with antiviral, cytotoxic, and immunomodulating actions. Which route of drug administration decreases the likelihood of systemic drug effects?Enteral Route of Medication
It refers to the drug metabolism whereby the drug concentration is significantly diminished before it reaches the systemic circulation, often due to the metabolism at the liver.
Which routes of administration can be used to avoid the firstAlternative routes of administration, such as insufflation, suppository, intravenous, intramuscular, inhalational aerosol, transdermal, or sublingual, avoid the first-pass effect because they allow drugs to be absorbed directly into the systemic circulation.
Which route of administration has the highest effect on metabolism of drugs?Intramuscular (IM)
Produces a faster effect than oral administration, however the rate of absorption depends greatly on the site of injection and on local blood flow.
How route of administration affects drug absorption?Since the bioavailability of a drug is directly dependent on the rate and extent of drug absorption at the site of administration, factors affecting drug absorption, including the route of administration directly affect the bioavailability of that drug.
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Which route of drug administration decreases the likelihood of systemic drug effects Quizlet
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