Pharmacology Chapter 9: Antibiotics

A nurse is caring for a 52-year-old client who has been diagnosed with a latent tuberculosis infection. The health care provider is considering ordering isoniazid (INH). The preexistence of what condition would require cautious use of INH in this client? A. cirrhosis of the liver B. folic acid deficiency C. hypertension D. glaucoma

A. Because hepatotoxicity is a potentially serious adverse effect of INH, the drug should be used cautiously in clients with liver disease.

The nurse is caring for a client who is taking tetracycline for Rocky Mountain spotted fever. The nurse notices that the client has developed painful mouth ulcers. The nurse knows that the client has developed what adverse reaction to the medication? A. Stomatitis B. Acne C. Hypersensitivity reaction D. Gastritis

A. Stomatitis is the development of ulcers in the mucous membranes of the oral cavity. It is an adverse reaction seen in clients taking tetracycline. Epigastric distress is another adverse reaction but is an inflammation of the stomach. A hypersensitivity reaction is usually seen as hives or wheals on the skin, and tetracycline is used in the treatment of acne.

A client is prescribed rifampin. What information should the nurse include in the client's medication education? A. The urine, tears, sweat, and other body fluids will be a discolored red-orange. B. It decreases hepatic enzymes and decreases metabolism of drugs. C. It has an increased serum half-life, so it is more effective than rifabutin. D. When taking it with warfarin, an increased anticoagulant effect occurs.

A. The client's urine, tears, sweat, and other body fluids will be a discolored red-orange. This adverse effect is harmless, but the client should be instructed on this adverse effect. The administration of this medication with warfarin will decrease the anticoagulant effect. The medication increases hepatic cytochrome P-450 3A4 enzyme and decreases serum concentrations. The serum half-life of rifampin is shorter than that of the medication rifabutin.

A client is allergic to penicillin and has been diagnosed with a genitourinary infection caused by Chlamydia trachomatis. Which medication will most likely be administered? A. erythromycin B. flumazenil C. acamprosate calcium D. atazanavir

A. A client who is diagnosed with a genitourinary infection that is caused by trachomatis and who is allergic to penicillin should be administered erythromycin since there is no known cross-reaction. Acamprosate calcium is administered as a substance abuse deterrent, not in place of penicillin. Atazanavir is an antiviral agent that is used to treat HIV infection, not Chlamydia trachomatis. Flumazenil is a benzodiazepine antagonist and not used for Chlamydia trachomatis.

A child has been diagnosed with acute otitis media. Before the child begins antibiotic treatment, what assessment should the nurse perform? A. Assess the child for allergies to penicillins. B. Assess the child for allergies to salicylates. C. Assess the child's immunization status. D. Assess whether the child has ever had tuberculosis skin test.

A. Amoxicillin is the preferred antibacterial agent for the treatment of acute otitis media. Because this medication is a penicillin, it is necessary to assess for allergies to these antibiotics. The child's immunization status, history of TB skin tests, and allergies to salicylates are not central to the child's care.

For what client would a broad-spectrum antibiotic be most appropriate? A. A client who has symptoms of infection but whose culture and sensitivity results are not yet available B. A client who has an oral temperature of 100.2° F (37.9° C) but no other signs or symptoms of infection C. A client whose urinary tract infection has been attributed to Escherichia coli D. A client with a respiratory infection who is 84 years old

A. Broad-spectrum antibiotics are often used to treat infections while awaiting the results of culture and sensitivity testing. The presence of a fever with no other signs of infection would not be an indication for the use of broad-spectrum antibiotics. Narrow-spectrum antibiotics are generally preferred when the causative microorganism of an infection is known. Advanced age is not an indication for broad-spectrum antibiotic use.

The nurse understands that which is the highest priority when teaching about antitubercular medications? A. Taking medications as prescribed B. Eating a well balanced diet C. Staying hydrated D. Monitoring sputum

A. For medications to be effective, it is most important that the nurse reinforce to the client that medications should be taken as prescribed and there should be no missed doses. Eating a well balanced diet, keeping hydrated and monitoring sputum are not medication priorities.

When preparing to administer a fluoroquinolone, the nurse understands that the majority of drugs belonging to this class are administered by which route? A. Oral B. Topical C. Intramuscular D. Subcutaneous

A. Most fluoroquinolones are administered orally; levofloxacin and moxifloxacin may also be given intravenously.

The health care provider is preparing to order rifampin and pyrazinamide for a female client with active tuberculosis. What question should the provider ask this client before confirming this order? A. "Are you pregnant?" B. "Have you ever experienced a miscarrage?" C. "Do you have a family history of diabetes?" D. "Are you allergic to penicillin?"

A. Pyrazinamide and streptomycin are contraindicated in pregnancy. A regimen of INH, rifampin, and ethambutol is usually used in the treatment of pregnant women.

A nurse is caring for a 6-year old child with a severe case of typhoid fever. The client was mistakenly administered tetracycline, which can cause adverse reactions. What could be a permanent effect in the child? A. Discoloration of the teeth B. Epigastric distress C. Visual disturbances D. Abdominal pain or cramping

A. Tetracyclines cause permanent yellow-gray-brown discoloration of the teeth in children less than 9 years of age. Epigastric distress is not a permanent effect of the drug. Abdominal pain or cramping and visual disturbances are adverse reactions of macrolides.

A client is to receive rifampin. Which would be most important for the nurse to include in the teaching plan for this client? A. "Your urine or sweat may become orange in color." B. "The drug can cause an allergic reaction." C. "You might experience some nausea or stomach upset." D. "Call your health care provider if you experience headache or dizziness."

A. This drug causes body fluids to turn orange. The client needs to be informed of this to avoid being frightened when it occurs. Any drug can cause a hypersensitivity reaction. Although this information is important, it is not the priority. GI adverse effects are common. Although this instruction would be important, it would not be the priority. Headache and dizziness are common CNS effects of the drug that do not need to be reported.

What decrease the absorption of fluoroquinolone?

Antacids, drugs containing iron or zinc

A client has been prescribed INH for the treatment of tuberculosis. The nurse teaches the client about dietary restrictions while taking this medication. What is the most important instruction? A. "Avoid excessive caffeine intake because this could increase the side effects of the medication." B. "Do not drink beer or red wine while taking this medication because a serious adverse reaction can occur." C. "Make sure to limit your protein intake, as increased protein delays absorption of the medication." D. "Take the medication with a full glass of water to prevent the mouth from becoming dry during therapy."

B. Because INH has some monoamine oxidase inhibitor activity, interactions may occur with tyramine-containing foods. INH may also interact with foods containing histamine. Clients should refrain from excessive intake of foods rich in tyramine, which include cheese and dairy products, beef or chicken liver, beer and ale, red wine, avocados, bananas, figs, raisins, caffeine, and chocolates. Because most people consume these food items, the diet is difficult to maintain.

A client has been prescribed ciprofloxacin IV for the treatment of cellulitis. After initiating the infusion of the client's first scheduled dose, the client develops a pronounced rash on the chest and arms. How should the nurse respond initially to this event? A. Slow down the rate so that the infusion takes place over 2 hours. B. Discontinue the infusion and inform the care provider promptly. C. Administer oral diphenhydramine to the client during the infusion. D. Administer an STAT dose of acetylcysteine.

B. Severe hypersensitivity reactions have occurred with the administration of fluoroquinolones. The nurse discontinues the antibiotic immediately if skin rash or other signs or symptoms occur. Administration of acetylcysteine or diphenhydramine is not indicated. Slowing down the rate of infusion would not address the problem as it relates to exposure to the medication. Neither the administration of acetylcysteine nor diphenhydramine is indicated initially. Acetylcysteine is prescribed to treat thick mucus lung secretions. Treatment with diphenhydramine would be ineffective if the ciprofloxacin were not first discontinued.

The drug's effect on what best reflects the major reason for avoiding the use of tetracyclines in children under 8 years of age? A. Kidneys B. Teeth C. Hearing D. Vision

B. Tetracyclines should be used with caution in children younger than age 8 years because the drugs can potentially damage developing teeth and bones. They do not affect hearing or vision. They are excreted in the urine, so caution is necessary if the client has underlying renal dysfunction; however, this is not the main reason for avoiding use in children.

gram-negative

Bacteria that accept a negative strain and are frequently associated with infections of the genitourinary and gastrointestinal tract.

Anaerobic

Bacteria that can survive without oxygen, which are often seen when blood flow is cut off to an area of the body.

Aerobic

Bacteria that depend on oxygen for survival.

gram-positive

Bacteria that take a positive strain and are frequently associated with infections of the respiratory tract and soft tissues.

A client is receiving a cephalosporin and an aminoglycoside as combination therapy. What assessment should the nurse prioritize? A. Coagulation studies B. Signs of disulfiram-like reaction C. Serum BUN and creatinine levels D. Complete blood count

C. Explanation: The nurse would need to assess renal function indicated by serum BUN and creatinine levels because combining cephalosporins with aminoglycosides increases the client's risk for renal toxicity. Coagulation studies would be important if the client was receiving a cephalosporin with an oral anticoagulant because there is an increased risk for bleeding. Combining cephalosporins with alcohol could result in a disulfiram-like reaction. Assessing the client's complete blood count would not be directly indicated by the combination of cephalosporins and aminoglycosides.

Antibiotic

Chemical that is able to inhibit the growth of specific bacteria or cause the death of susceptible bacteria.

Pyrazinamide and Streptomycin.

Contraindicated in pregnancy. A regimen of INH, rifampin, and ethambutol is usually used in the treatment of pregnant women.

A client, hospitalized with active tuberculosis, is receiving antitubercular drug therapy. When it becomes apparent that the client is not responding to the medications, what condition will the primary health care provider identify as a possible cause? A. vancomycin-resistant Staphylococcus aureus B. methicillin-resistant Staphylococcus aureus C. human immunodeficiency virus (HIV) D. drug-resistant tuberculosis.

D. A client who is being treated with antitubercular drug therapy and is not responding to the medication regime is most likely experiencing drug-resistant tuberculosis. Human immunodeficiency virus causes tuberculosis to move more rapidly. This scenario does not provide any indication that the tuberculosis is related to the diminished client response. The scenario does not identify methicillin-resistant or vancomycin-resistant Staphylococcus aureus.

A client diagnosed with Chlamydia is allergic to penicillin. What medication could be used as a substitute for penicillin in this situation? A. chloramphenicol B. tetracycline C. doxycycline D. erythromycin

D. Erythromycin is used as a penicillin substitute in clients who are allergic to penicillin and for prevention of rheumatic fever, gonorrhea, syphilis, pertussis, and chlamydial conjunctivitis in genitourinary infections caused by Chlamydia trachomatis and intestinal amebiasis caused by Entamoeba histolytica. None of the other options are typically used as a substitute to account for an allergy to penicillin when treating chlamydia.

Administration of what type of antibiotic by the nurse would be most likely to cause a superinfection? A. narrow spectrum B. bactericidal C. bacteriostatic D. broad spectrum

D. One offshoot of the use of anti-infectives, especially broad-spectrum anti-infectives, is destruction of the normal flora, allowing opportunistic pathogens to invade tissue and cause a superinfection. Narrow-spectrum anti-infectives are less likely to kill normal flora, although it is not impossible. A drug may be bactericidal, meaning it kills the pathogen; or bacteriostatic, meaning it prevents reproduction of the pathogen, but this is not related to superinfections.

A group of nursing students are reviewing information about penicillins. The students demonstrate understanding of the information when they identify the action of penicillinase as causing bacterial resistance by which mechanism? A. destruction of the beta-lactam ring of the penicillin B. destruction of the penicillin cell wall C. rupture of the penicillin membrane D. enzymatic inactivation of the penicillin

D. Penicillinase is an enzyme produced by certain bacteria that inactivates the penicillin. Some bacteria produce other enzymes called beta lactamases which destroy the beta-lactam ring of penicillin. Penicillin is a drug that attaches to the bacteria receptor site on the bacterial wall; penicillin does not have a cell wall or membrane.

A patient with TB is admitted to a health care facility. The nurse is required to administer an antitubercular drug through the parenteral route to this patient. Which of the following precautions should the nurse take when administering frequent parenteral injections? A. Administer streptomycin to promote nutrition. B. Monitor patient's vital signs each morning. C. Monitor signs of liver dysfunction weekly. D. Rotate injection sites for frequent parenteral injections.

D. The nurse should be careful to rotate injection sites when administering frequent parenteral injections. At the time of each injection, the nurse inspects previous injection sites for signs of swelling, redness, and tenderness. The nurse should monitor any signs of liver dysfunction monthly in patients who are being administered antitubercular drugs. The nurse should ensure that pyridoxine, and not streptomycin, is administered to the patient to promote nutrition, but this is only administered if the patient has been living in impoverished conditions and is malnourished. The nurse should monitor patient's vital signs every four hours and not once every morning.

A 9-year-old client has been admitted to the pediatric unit after being diagnosed with pertussis. The pediatric nurse is processing the client's admission orders and notes that IV demeclocycline has been prescribed. After beginning this treatment, the nurse should confirm the results of what laboratory test? A. mean corpuscular volume (MCV) B. d-dimer C. bilirubin D. blood urea nitrogen (BUN)

D. When administering demeclocycline, it is important to monitor the client's BUN. Increases in the BUN are secondary to antianabolic effects. Bilirubin levels would only be important in the presence of liver toxicity. A d-dimer test is a blood test that measures a substance that is released when a blood clot breaks up. Health Care Providers prescribe the d-dimer test, along with other lab tests and imaging scans, to help check for blood-clotting problems. Mean corpuscular volume (MCV) laboratory test, as part of a standard complete blood count (CBC), is used along with other RBC indices (MCH and MCHC) to help classify the cause of anemia based on red cell morphology. Neither a d-dimer nor MCV values are relevant to this situation.

Synergistic

Drugs that work together to increase drug effectiveness.

Natural Penicillins

Exert a bactericidal effect on bacteria it targets the bacterial cell wall to destroy the bacteria

What does the nurse need to monitor when clients taking Demeclocycline?

Is important to monitor the client's BUN

Aminoglycosides toxicity

Ototoxicity and nephrotoxicity

Secondary TB Drugs

Para-aminosalicylic acid, cycloserine, and ethionamide. Used when there is a resistance to the primary anti-TB drugs

Ciprofloxacin

Photosensitivity.

Primary TB Drugs

Pyrazinamide, rifampin and ethambutol are primary drugs

Vancomycin adverse effects

Red man syndrome. With this syndrome, the client's face and upper trunk becomes bright red, and it has led to cardiovascular collapse.

Tetracyclines

Should always be administered with a full glass of water and on an empty stomach (except minocycline and tigecycline may be taken with food).

Aminoglycosides and potent diuretics

Should avoid being combined. It increases the incidence of ototoxicity, nephrotoxicity, and neurotoxicity

INH (Isoniazid)

Should avoid eating tyramine, histamine-rich foods, and foods containing caffeine. Also, the client should be told to avoid consuming alcohol on a daily basis. Cheese, dairy products, chicken liver, beer, ale, bananas, and figs are rich in tyramine. May cause hyperglycemia (high blood sugar).

Rifampin and Isoniazid drugs

Should be used during the second phase of standard treatment.

Disulfiram-like reaction

The client should avoid consuming alcoholic beverages for at least 72 hours after completing the drug course. Flushing, throbbing in the head and neck, respiratory difficulty, vomiting, sweating, chest pain, and hypotension are symptoms a nurse might observe in a client having this reaction.

What is Tetracycline used for?

To treat Mycoplasma, Chlamydia, and Rickettsia

Ototoxicity

Toxic to ear

Nephrotoxicity

Toxic to kidneys

Neurotoxicity

Toxic to nerves and nerve tissue

Hepatotoxicity

Toxic to the liver

Tuberculosis

Tuberculosis is an infectious disease that usually affects the lungs but may involve most parts of the body, including lymph nodes, meninges, bones, joints, kidneys, and the gastrointestinal tract. The nurse should obtain baseline liver function test values and schedule several liver function tests throughout therapy. In addition, a nurse should ensure a baseline A1C evaluation for clients who are diabetics, because INH may cause hyperglycemia. Clients with preexisting anemias should have a baseline complete blood count (CBC), because they are at risk for blood disorders.

Rich in histamine

Tuna, brine, and yeast extracts

Dapsone

Used for leprosy and cannot be used in combination with Isoniazid or any other drug for TB.

Cephalosporins

Used to treat urinary tract infections, skin infections, and hospital-acquired pneumonias.

When do prescribers order tetracycline

When penicillin is contraindicated to treat infections caused by Klebsiella, Neisseria gonorrhoeae, Treponema pallidum, Listeria monocytogenes, Clostridium, Bacillus anthracis, Fusobacterium fusiforme, and Actinomyces.