Pharmacology Chapter 9 - Antiinfective Medications

generally how long is the course of penicillin?

10 days

how many generations of cephalosporins are there?

4 generations

pseudomembranous colitis

a condition now commonly seen in hospitals and nursing homes that arises from superinfection caused by clostridium difficile

bacteria

a large domain of single celled prokaryotic microorganisms. they have a wide range of shapes and characteristics, such as anaerobic or aerobic rods or gram positive or gram negative

fungus

a member of a large group of eukaryotic organisms that include microorganisms such as yeasts and molds; grow in irregular masses without root stems or leaves and live and feed on other organisms

virus

a small infectious agent that can replicate only inside the living cells of organisms

sulfonamides

a type of antibiotic that have a bacteriostatic effect against a wide range of gram positive and gram negative microorganisms by inhibiting folic acid synthesis which is essential for cell growth and function

antibiotics

a type of antimicrobial that is made from the living organisms (such as penicillins) other chemcials are synthetics (such as sulfonamides) or a combination of synthetic and naturally occurring microorganisms

what is the most common adverse reaction in patents taking cephalosporins?

acute hypersensitivity

bactericidal

agents that kill the bacteria

bacteriostatic

agents that limit or slow the growth of the bacteria, wearing or eventually leading to the death of the bacteria

antibiotics adverse reactions include..

allergy (penicillin and sulfa drugs cause the most allergies), ototoxicity, nephrotoxicity, and hepatotoxicity, and GI distress so sever that it may require stopping the drug, neuropathy, fixed drug eruptions (usually a single spot that itches) nausea, vomitting, epigastric distress, anemia and blood dyscrasis

amikacin, gentamicin, gentamicin sulfate, kanamycin, neomycin, paromomycin, streptomycin, tobramycin are all examples of what kind of broad spectrum antibiotic?

aminoglycosides

trough and peak needs to be closely monitored for what broad spectrum antibiotic?

aminoglycosides

vancomycin and other antibiotics that are toxic, such as aminoglycosides, can cause what to occur?

an increase in toxicity in patients body

pathogen

an organism that causes an infection

parasite

an organism, protozoa, or worm that lives on or in another organism and draws it's food from the other organism

what drugs may cause less absorption of the sulfonamides?

antacids

what medication can decrease the absorption of penicillins?

antacids

what two drugs may decrease fluoroquinalines absorption?

antacids and ferrous sulfate

what must be done to find the trough level of aminoglycosides before the next scheduled dose is given?

antibiotic blood level. the sample will show the lowest blood level of the antibiotic rather than a blood level at a higher range. the lowest blood level will determine whether the dosage needs to be adjusted to stay within the therapeutic range and not go above the toxic level or below the effective level

what must be monitored during the course therapy of ahminoglycosides?

antibiotic blood levels, blood urea nitrogen and creatinine levels (urine test) (due to nephrotoxicity) and hearing tests

ototoxicity is increased is increased when aminoglycosides is taken with what other drugs?

aspirin, furosemide, ethacrynic acid and many other drugs

what is the action of fluoroquinolones?

bactericidal and act by interfering with bacterial DNA synthesis, which makes it difficult for the pathogens to reproduce themselves and attack other cells

why should tetracycline products that are out of date not be used?

because if they are used it may lead to damage of the proximal renal tubules.

why must provider know if patient is breastfeeding or pregnant before receiving broad spectrum antibiotics?

because many broad spectrum antibiotics cross the blood brain barrier and are secreted in breast milk

why should tetracycline used with caution in patients with poor liver function?

because the drug may cause hepatotoxicity and azotemia

why must patients taking aminoglycosides get their blood levels checked?

because they have a narrow therapeutic range, so the blood levels of these drugs should be closely watched to avoid toxic levels

hematuria

blood in the urine

what broad spectrum antibiotic competes with probenecid?

carbapenem

what broad spectrum antibiotic may reduce the activity of valproic acid, which is given to prevent seizures

carbapenem

what are the adverse reactions of vancomycin?

causes frequent but minor side effects such as flushing, and hypotension. can cause red man syndrome which is a rash found on the upper body that is produced by histamine released reaction. high doses may produce nephrotoxicity and ototoxicity. hypersensitivity reactions can occur as well

a percentage of patients with penicillin allergy may also display a cross sensitivity to what?

cephalosporins

cefadroxil, cefazolin, cephalexin, cefaclor, cefotxitin, cefprozil, cefuroxmie, cefdinir, cefixime, cefotaxime, cefpodoxime, ceftazidime, ceftibuten, ceftizoxmie, ceftriazone, and cefepime are all examples of what kind of broad spectrum antibiotic?

cephalosporins

antimicrobials

chemicals that kill or damage the pathogenic organisms. these are further classified by their chemical structures or by their mechanisms of action

what drug is the drug of choice for anthrax exposure in bioterrorist attacks?

ciprofloxacin (Cipro)

C&S

culture and sensitivity. swapping area for the bacteria, spreading it on a dish to let it grow with different kinds of penicillins in the dish and whichever penicillin has the strongest effect gets prescribed

alcohol taken with cephalosporins may produce what?

disulfiram reaction resulting in severe flushing, vomiting, and collapse

how do you find what kind of penicillin to prescribe to pt?

do a C&S (culture and sensitivity)

how are aminoglycosides dosages calculated?

dosed based off the patents weight and is increased or decreases based on blood levels so an effective level is maintained

what kind of tetracycline is a particular effective drug for the older adult population because it may be taken twice daily and is usually tolerated even by some individuals who have reduced renal function, chronic kidney disease and who are older patients...

doxycycline (vibramycin)

broad spectrum drugs

drugs that are effective against both gram positive and gram negative bacteria. a large variety of organisms

narrow spectrum drugs

drugs that are effective against only a few gram positive or gram negative bacteria

overuse of penicillin encourages what?

encourages drug resistance

what are the contraindications and precautions in giving antibiotic drug therapy?

find out if patient had prior renal damage, hepatic problems, systemic lupus erythematous, alcoholism, or drug that may interact with an antibiotic. pregnancy, breast feeding, age, occupation

what should you do before giving a patient an IM penicillin injection?

find patients blood pressure and pulse for a baseline before administration

arthropathy (joint pain and disease) and an increased risk for achillie tendon rupture have also been identified with what class of broad spectrum antibiotics?

fluoroquinalones

what type of broad spectrum antibiotic should not be taken with multivitamins or mineral supplements because they reduce the absorption of the antibiotic by as much as 90%?

fluoroquinalones

what is the main type of antibiotics in the "other" category of the 5 broad spectrum antibiotics?

fluoroquinolones

what should you not drink within an hour of administering penicillin?

fruit juices

all four generation of fluoroquinolones are effective against what kind of bacteria?

gram negative bacteria

the newer genrations of fluoroquinolones are significantly more effective against what kind of microbes?

gram positive microbes

macrolides and anesthetic agents and anticonvulsant drugs may interact to cause what?

high serum drug levels and toxicity

dosages of fluoroquinalones must be adjusted in patients with what?

impaired renal functions

adverse reactions of sulfonamides..

include many minor but irritating problems such as a headache, drowsiness, fatigue, dizziness, vertigo, tinnitus, hearing loss, insomnia, anorexia, nausea, vomiting, stomatitis (inflammation of the mouth), abdominal pain, rash, fever, malaise (weakness) pruritus (itching), dermatitis and local irritation, crystalluria (formation of crystals in the urine) and hematuria (blood in the urine)

how is carbapenem administered?

intravenously

use of ampicillin and oral contraceptives together causes what...

it can produce menstrual irregularities and unplanned pregnancies because the penicillin reduces the level of available hormone

what is vancomycin used for?

it is usually reserved for serve gram positive infections such as staphylococcus aureus and pneumocystis pneumoniae. it is one of the most powerful antibiotics to which most organisms are still sensitive. it is used for treating MRSA infections

probenecid does what to the body when taking it with penicillin?

it prolong blood levels of penicillin by blocking its renal clearance

when fluoroquinalones are taken with warfarin what will occur?

it will increase warfarins anticoagulant effects

sulfonamides effects may be decreased by...

local anesthetics

azithromycin, clarithromycin, dirithromycin, erythromycin are examples of what kind of broad spectrum antibiotics?

macrolides

what kind of broad spectrum antibiotic increase the action of oral anticoagulants, digoxin, and many other kinds of drugs and thus may produce both drug and kidney toxicity?

macrolides

what kind of broad spectrum atibitotic is used as alternatives to penicillin for many infections for which organisms have developed penicillin resistance?

macrolides

adverse reactions of sulfonamides include..

many minor but irritating problems

other bacteriostatic antibiotics such as tetracycline and erythromycin may do what to penicillin?

may decrease the bactericidal effects of penicillin

what are the adverse effects of carbapenem?

may produce pseudomembranous colitis, hypersensitivity reactions, and impaired renal function, nausea, vomiting, diarrhea, headache, rash, sepsis, constipation, apnea, shock and pruritus were all reported

what are the most common adverse reactions seen in patients using macrolides?

mild abdominal pain, nausea, and diarrhea

for systemic infections, patients on aminoglycosides must have the antibiotic administered how?

must be given paternally because they are poorly absorbed from the GI tract

what are the most common side effects of fluoroquinalones and occur in up to 20% of patients?

nausea vomiting and diarrhea. they may also have headache, dizziness, and abnormal heart rhythms

besides acute hypersensitivity, what are other adverse reactions seen in patients taking cephalosporins?

nausea, vomiting, diarrhea, minor rash and itching, major anaphylaxis, nephrotoxicity (the incidence is greater in older adult patients and patients with poor renal function) there may also be severe pain at the injection site

aminoglycosides may cause serious adverse effects such as...

nephrotoxicity that is usually reversible if the drug is stopped quickly, may produce permanent damage to the inner ear (ototoxicity), or hearing impairment, dizziness, loss of balance, ringing in the ears, and persistent headache or other types of neurotoxicity

sulfonamides may increase the effects of what oral medications?

oral anticoagulants, methotrexate, sulfonylureas, thiazide diuretics, phenytoin and uricosuric agents

if fluoroquinalones are taken with coffee or caffeine-containing products what can occur?

patients may develop excessive nervousness, anxiety, or tachycardia

cephalosporins are given to patients who can not take what kind of antibiotic?

patients who are unable to take penicillin

what antibiotic is considered the safest antibiotic?

penicillin

penicillin may change the results of some lab tests causing

penicillin may causes increase bleeding time when the platelet count is normal, giving a false positive urine protein test and lupus erythmeatosus cell test

what other antibiotic may be less effective when taken with sulfonamides?

penicillins

fluoroquinalones are safe drugs but are not given to who?

pregnant women

how can superinfections develop?

prescribing an antibiotic when it is not necessary like prescribing penicillin for a viral infection, all it will do is kill the normal flora and result in superinfection

which conditions may be contraindications of prescribing penicillin?

prior history of penicillin, allergy, asthma or hypersensitivity to procaine or tartrazine and find out if the patient is pregnant or breastfeeding

allergies to penicillin cause what symptoms...

produces rash, erythema (redness or inflammation) urticaria (hives) angioedema (swelling of the skin and mucus membranes) laryngeal edema (swelling or the larynx) and anaphylaxis

what may develop with overdosage and innate the patient may have a sever hypersensitivity to sulfonamides?

proteinuria (large amount of protein in the urine) and some sever cases of anaphylactic shock

fluoroquinalones are excreted by...

renel mechanisms

fluoroquinolones are used as alternatives to other antibiotics in the treatment of...

respiratory, GI, gynecologic, skin, and soft tissue infections

why must patients taking sulfonamides be warned to stay out of the sun?

severe photosensitivity can occur if the patients skin is exposed to excessive amounts of sunlight or ultraviolet light

a patient taking sulfonamides should contact their health care provider if what adverse reactions occur?

skin rash, blood in the urine, bruises, nausea, or other adverse effects of therapy develop because these may indicate develop of more severe reactions

generations of drugs

some drugs have become more refined, purified, and sensitive as a result of long term testing. the original drugs are referred to as "first generation"

what to tell older patients when taking fluoroquinalones?

stay hydrated

patients with an allergy or hypersensitivity to thiazide diuretics may also display a cross-sensitivity to what kind of antibiotic?

sulfonamides

what are sulfadiazine, sulfasalazine, sulfonamide combination vaginal product, and trimethoprim/sulfamethoxazole are what kind of drugs?

sulfonamides

what may develop after long term use of tetracylines?

superinfections causing diarrhea, oral thrush, or vaginal itching

demeclocycline, doxycycline, minocycline, oxytetracycline, tetracyclines are all what kind of broad spectrum antibiotic?

tetracycline

carbapenem drugs such as invanz, mere, and primaxin are used for what?

the are used in acute infections caused by bacterial meningitis, intraabdominal infections, skin and skin structure infections

gentamicin and amikacin (types of aminoglycosides) are used in the treatment of...

the treatment of serious aerobic gram negative infections include those caused by E. Coli, serratia, proteus, klebsiella and pseudomonas; aerobic gram negative bacteria, mycobacteria and some protozoans

how are fluoroquinalones administered?

they are administered orally only once or twice per day with food to decrease adverse GI effects

what are the actions of cephalosporins?

they are bactericidal and weaken the bacteria by interfering with building the bacterias cell wall. broad spectrum activity abasing gram negative organisms

what is the action of tetracyclines?

they are bacteriostatic agents, they act by interfering with the ability of the bacteria to make protein. without this protein the bacteria cannot stay alive. they are important broad spectrum drugs, effective against many gram positive and negative bacteria

what are the action of macrolides?

they are either bactericidal or bacteriostatic depending on the organisms and the dose used. they weaken the bacteria by limiting the production of protein which is essential to the life of bacteria

tetracycline adverse effects include...

they are relatively safe but commonly produce mild episodes of nausea, vomiting, and diarrhea that may require stopping the drug. the effects are often dose related and they result from irritation of the GI tract changes in the normal bacteria in the bowel and over growth of yeast

what are macrolides used for?

they are the drug of choice in streptococcus infections, haemophilus influenzae, mycoplasma pneumoniae, chlamydia infections, legionnaires' disease and the treatment of pertussis ("whooping cough")

what are tetracyclines used for?

they are the first drug of choice is only a few types of disease such as lyme disease, stomach ulcer caused by helicopter pylori, chlamydia, rocky mountain spotted fever, cholera, typhus and many adolescents use it as a preventative or treatment of acne

macrolides may be administered what ways?

they can be administered orally and paternally. topical absorption should be avoided to prevent sensitization

other drug products such as probenecid may do what to the excretion of cephalosporins?

they may decrease elimination of the drugs by the kidneys

indomethacin, phenylbutazone or aspirin may do what to serum penicillin levels?

they may increase blood serum levels of penicillin

short acting sulfonamides usually require what kind of dosage at first?

they require a loading dose at first which is a dose bigger than the dose that will be regularly taken

how should sulfonamides be taken?

they should be taken on an empty stomach, either one hour before or two hours after meals along with a full glass of water. they are fully and quickly absorbed that way.

what are cepahlopsporins used for?

this antibiotic is used for serious infections like bacteremia, septicemia (infections of the blood), and infections of the lower respiratory tract, central nervous system, genitourinary system, joints and bones

what is the action of aminoglycosides?

this antibiotic weaken the bacteria by limiting the production of protein which is essential to the life of bacteria so they are bactericidal

vancomycin actions

this drug is bactericidal, it inhibits the building of the bacterial cell wall

carbapenem actions

this is a miscellaneous broad spectrum antibiotic that is effective against gram positive and gram negative bacteria. it penetrates bacteria cells and interferes with the making of the vital cell wall parts which lead to death making this drug bactericidal

penicillins

this was the main antibiotic for years. it interferes with the creation and repair of the cell wall of the bacteria. they also bind or stick to specific enzymes that the bacteria need so that the bacteria can not use them. this process makes the bacteria cell wall weak and allows it to break down more easily. these drugs are the broad spectrum drug of choice for susceptible gram positive gram negative organisms.

why must the patient taking macrolides stay hydrated?

to ensure a minimum urine output of 1500 mL decreases the chances of renal toxicity

why must a patient on sulfonamides drink at least 1.5 L/day?

to prevent formation of crystals in the urine

what are penicillins used for?

used for staph infections, step infections, ear infections, prophylactic treatment against bacterial endocarditis in patient with rheumatic or congenital heart disease before they have dental procedures or surgeries of the upper respiratory tracts, genitourinary tract or GI tract and some may be useful against organisms used by terrorist as bioweapons

some aminoglycosides is used for what?

used in stroke patients, patients with rheumatoid arthritis and to sterilize bowel before intestinal surgery

streptomycin (SM a aminoglycosides) is used in the treatment of...

used in the treatment of TB

how is vancomycin administered?

usually administered intravenously very slowly (over the course of an hour) to avoid red man syndrome. and it is not absorbed through the GI tract. very important to monitor the peak and trough levels

what are sulfonamides used for?

usually used to treat acute and chronic urinary tract infections, acute otitis media, toxoplasmosis and preventive therapy in cases of recurrent rheumatic fever, some strains of bacillus anthracis, streptococcus progenies, streptococcus pneumoniae, and other less common organisms. used in the treatment of ulcerative colitis and preoperative and postoperative therapy for bowel surgery

cholestyramine and colestipol decrease the absorption of what broad spectrum antibiotic?

vancomycin

nephrotoxicity is increased in patients taking aminoglycosides and what other antibiotic?

vancomycin

minocycline may cause what? as long as other tetracyclines but minocyclines for the most part..

vertigo

secondary infection

when one infection follows another. e.g.; patient had a viral infection and the antiviral caused the bodies defenses to be weakened resulting in a bacterial infection afterwards

superinfection

when other organisms that are not sensitive to prescribed antibiotic (for example yeast) are able to multiply, overgrow, and get out of control because the antibiotic also killed the normal flora that would have kept them under control

mixed infection

when pt has an infection and catches a secondary infection and both are present at the same time

what is the peak of the antibiotic blood levels?

when the antibiotic blood level is at a higher range

what is the trough of the antibiotic blood levels?

when the antibiotic blood levels are at the lowest level

what are the contraindications in the use of tetracylines?

women who are pregnant or breast feeding, children less than 8 years of age because the category D agent may cause inadequate bone or tooth development, produce permanent yellow-brown tooth discoloration, and/or cause permanent damage to a developing fetus