Chemotherapeutic Agents Pt. 2 and 3 Flashcards
The exact mechanism of action is unknown.
Pyrazinamide
May be bacteriostatic or bactericidal, depending on its concentration at the infection site and on the susceptibility
of the infecting organism
Pyrazinamide
Pyrazinamide
Contraindications and cautions
a. Contraindicated in clients with hypersensitivity
b. Used with caution in clients with diabetes mellitus, renal impairment, or gout, and in children
c. May decrease the effects of allopurinol, colchicine, and probenecid
d. Cross-sensitivity is possible with isoniazid, ethionamide, or nicotinic acid.
Pyrazinamide
Side and adverse effects
a. Increases liver function tests and uric acid levels
b. Arthralgia, myalgia
c. Photosensitivity
d. Hepatotoxicity
e. Thrombocytopenia
Inhibits mycobacterial DNA-dependent RNA polymerase and suppresses protein synthesis
Rifabutin
Used to prevent disseminated Mycobacterium avium complex (MAC) disease in clients with advanced HIV infection
Rifabutin
Used to treat active MAC disease and tuberculosis in clients with HIV infection
Rifabutin
Rifabutin
Cautions
a. Can affect blood levels of some medications, including oral contraceptives and some medications used to treat HIV infection
b. A nonhormonal method of birth control should be used instead of an oral contraceptive.
Used only for pulmonary tuberculosis
Rifapentine
Can affect blood levels of some medications, including oral contraceptives and warfarin, and some medications used to treat HIV infection
Rifapentine
Rifapentine
Side and adverse effects
a. Red-orange–colored body secretions
b. Hepatotoxicity
a. Mechanism of action is unknown.
b. Used to treat MDR-TB when significant resistance to other medications is expected
c. Administered intramuscularly
Capreomycin sulfate
Capreomycin sulfate
Contraindications and cautions
a. The risk of nephrotoxicity, ototoxicity, and neuromuscular blockade is increased with the use of aminoglycosides or loop diuretics.
b. Used with caution in clients with renal insuf ficiency, acoustic nerve impairment, hepatic disorder, myasthenia gravis, or parkinsonism
c. Not administered to clients receiving streptomycin
Capreomycin sulfate
Side and adverse effects
a. Nephrotoxicity
b. Ototoxicity
c. Neuromuscular blockade
OTHER ANTIBIOTICS
Ketolide
- telithromycin
Lincosamides
- clindamycin
- lincomycin
Lipoglycopeptides
- televacin
Macrolides
- azithromycin
- clarithmycin
- arythromycin
Monobactam
- aztreonam
binds to specific ribosome subunits, leading to cell death in susceptible bacteria, which includes several strains resistant to other antibiotics
Telithromycin
KETOLIDES
PHARMACOKINETICS
- It is rapidly absorbed through the GI tract, reaching peak levels in 1 hour.
- distributed, may cross the placenta, and does pass into breast milk.
- metabolized in the liver with a half-life of 10 hours.
- excreted in the urine and feces
KETOLIDES
CONTRAINDICATION AND CAUTIONS:
- known allergy to any component of the drug or to macrolide antibiotics
- known congenital prolonged QT interval, bradycardia, or any proarrhythmic condition with myasthenia gravis, which is a black box warning with this drug
- Use with caution in cases of renal or hepatic impairment
- Use with caution with pregnant and lactating patients
KETOLIDES
ADVERSE EFFECTS:
- GI tract: nausea, vomiting, taste alterations, and the potential for pseudomembranous colitis.
- Superinfections
- Serious hypersensitivity reactions, including anaphylaxis
react at almost the same site in bacterial protein synthesis
LINCOSAMIDES
These drugs are used in the treatment of severe infections when a less-toxic antibiotic cannot be used.
LINCOSAMIDES
LINCOSAMIDES
PHARMACOKINETICS
- are rapidly absorbed from the GI tract or from IM injections
- metabolized in the liver and excreted in the urine and feces.
- cross the placenta and enter breast milk
LINCOSAMIDES
CONTRAINDICATIONS AND CAUTIONS
- with caution in patients with hepatic or renal impairment,
- Use during pregnancy and lactation only if the benefit clearly outweighs the risk to the fetus or neonate
LINCOSAMIDES
ADVERSE EFFECTS:
- with caution in patients with hepatic or renal impairment,
- Use during pregnancy and lactation only if the benefit clearly outweighs the risk to the fetus or neonate
are semisynthetic derivatives of vancomycin
LIPOGLYCOPEPTIDES (TELEVANCIN)
They inhibit bacterial cell wall synthesis by interfering with the polymerization and cross-linking of peptidoglycans
LIPOGLYCOPEPTIDES (TELEVANCIN)
They bind to the bacterial membrane and disrupt the membrane barrier function causing bacterial cell death
LIPOGLYCOPEPTIDES (TELEVANCIN)
It is only approved for use in treating complicated skin and skin-structure infections in adults
LIPOGLYCOPEPTIDES (TELEVANCIN)
LIPOGLYCOPEPTIDES (TELEVANCIN)
PHARMACOKINETICS
- available as an IV drug only.
- It is rapidly absorbed with peak levels occurring at the end of the infusion.
- The drug is widely distributed, may cross the placenta, and may pass into breast milk.
- Its site of metabolism is not known; It has a half-life of 8 to 9 hours.
- It is excreted in the urine.
LIPOGLYCOPEPTIDES (TELEVANCIN)
CONTRAINDICATIONS AND CAUTIONS
- contraindicated with known allergy to any component of the drug
- Black Box Warning with pregnant and lactating patients
LIPOGLYCOPEPTIDES (TELEVANCIN)
ADVERSE EFFECTS:
- nausea, vomiting, taste alterations, diarrhea, loss of appetite, and risk of C. difficile diarrhea.
- Nephrotoxicity
- There is a risk of prolonged QTc interval.
- A transfusion reaction called red man syndrome with flushing, sweating, and hypotension can occur with rapid infusion.
- Infusion site reactions with pain and redness.
are antibiotics that interfere with protein synthesis.
MACROLIDES
Macrolides include
erythromycin (Ery-Tab, Eryc, and others), azithromycin (Zithromax), clarithromycin (Biaxin), and dirithromycin (Dynabac).
may be bactericidal or bacteriostatic, exert their effect by binding to the bacterial cell membrane and changing protein
MACROLIDES
MACROLIDES
PHARMACOKINETICS
- are widely distributed throughout the body; they cross the placenta and enter the breast milk
- absorbed in the GI tract
Erythromycin
PHARMACOKINETICS
metabolized in the liver, with excre tion mainly in the bile to feces
Azithromycin and clarithromycin
PHARMACOKINETICS
mainly excreted unchanged in the urine, making it necessary to monitor renal function
Dirithromycin
PHARMACOKINETICS
converted from the prodrug dirithromycin to erythromycylamine in the intestinal wall and excreted through the feces
MACROLIDES
CONTRAINDICATIONS AND CAUTIONS:
- contraindicated in patients with a known allergy to any macrolide
- Ocular preparations are contraindicated for viral, fungal, or mycobacterial infections of the eye
- Use with caution in patients with hepatic dysfunction,renal disease, pregnant and lactating women
MACROLIDES
ADVERSE EFFECTS:
- abdominal cramping, anorexia, diarrhea, vomiting, and pseudomembranous colitis.
- Other effects include neurological symptoms such as confusion, abnormal thinking, and uncontrollable emotions
- hypersensitivity reactions ranging from rash to anaphylaxis
- superinfections
structure is unique, and little cross-resistance occurs
aztreonam
It is effective against gram-negative enterobacteria and has no effect on grampositive or anaerobic bacteria.
MONOBACTAM (AZTREONAM)
disrupts bacterial cell wall synthesis, which promotes leakage of cellular contents and cell death in susceptible bacteria
MONOBACTAM (AZTREONAM)
The drug is indicated for th treatment of urinary tract, skin, intra-abdominal, and gynecological infections, as well as septicemia.
MONOBACTAM (AZTREONAM)
MONOBACTAM (AZTREONAM)
PHARMACOKINETICS
- Aztreonam is available for IV and IM use only
- half-life is 1.5 to 2 hours.
- The drug is excreted unchanged in the urine.
- It crosses the placenta and enters breast milk
MONOBACTAM (AZTREONAM)
CONTRAINDICATIONS AND CAUTIONS
- contraindicated with any known allergy to aztreonam.
- Use with caution in patients with a history of acute allergic reaction to penicillins or cephalosporins
- caution with renal or hepatic dysfunction and in pregnant and lactating women
MONOBACTAM (AZTREONAM)
ADVERSE EFFECTS
- The adverse effects associated are relatively mild.
- Local GI effects include nausea, GI upset, vomiting, and diarrhea.
- Hepatic enzyme elevations
- Other effects include inflammation, phlebitis, and discomfort at injection sites, as well as the potential for allergic response, including anaphylaxis.
An infection caused by a fungus is called a
mycosis
Fungi differ from bacteria in that the fungus has a _______________________ that is made up of _______________________________________ and a _________________that contains ___________________.
rigid cell wall; chitin and various polysaccharides; cell membrane; ergosterol
resistant to antibiotics
ANTI-FUNGAL AGENTS
a large group of antifungals used to treat systemic and topical fungal infections
AZOLE ANTIFUNGALS
AZOLE ANTIFUNGALS include
fluconazole (Diflucan), itraconazole (Sporanox), ketoconazole (Nizoral), posaconazole (Noxafi l), terbinafi ne (Lamisil), and voriconazole (Vfend)
bind to sterols and can cause cell death (a fungicidal effect) or interfere with cell replication (a fungistatic effect)
AZOLE ANTIFUNGALS
Ketoconazole
PHARMACOKINETICS
absorbed rapidly from the GI tract, and metabolized in the liver and excreted through the feces.
Fluconazole
PHARMACOKINETICS
reaches peak levels within 1 to 2 hours after administration, excreted unchanged in the urine.
Itraconazole
PHARMACOKINETICS
slowly absorbed from the GI tract and is metabolized in the liver, excreted in the urine and feces.
Posaconazole
PHARMACOKINETICS
given orally, has a rapid onset of action, metabolized in the liver and excreted in the feces
Terbinafine
PHARMACOKINETICS
rapidly absorbed from the GI tract, extensively metabolized in the liver, and excreted in the urine with a half-life of 36 hours.
Voriconazole
PHARMACOKINETICS
reaches peak levels in 1 to 2 hours if given orally, and metabolized in the liver with a half-life of 24 hours and is excreted in the urine.
AZOLE ANTIFUNGALS
CONTRAINDICATIONS AND CAUTIONS
- Contraindicated with patients with hepatic failure
- Use in caution for liver and renal impairment
- Should not be used in pregnancy and lactating mothers
AZOLE ANTIFUNGALS
ADVERSE EFFECTS:
- Many of the azoles are associated with liver toxicity
- can cause severe effects on a fetus or a nursing baby.
ECHINOCANDIN ANTIFUNGALS include
anidulafungin, caspofungin, and micafungin
work by inhibiting glucan synthesis.
ECHINOCANDIN ANTIFUNGALS
is an enzyme that is present in the fungal cell wall but not in human cell walls
Glucan
PHARMACOKINETICS
Anidulafungin
- is given as a daily IV infusion for at least 14 days.
- metabolized by degradation and excreted in the feces
Caspofungin
PHARMACOKINETICS
- is available for IV use.
- slowly metabolized in the liver and bound to protein and widely distributed throughout the body excreted through the urine.
PHARMACOKINETICS
Micafungin
- is an IV drug
- It has a rapid onset
- excreted in the urine
CONTRAINDICATIONS AND CAUTIONS:
Anidulafungin
- may cross the placenta and enter breast milk
- should not be used by pregnant or lactating women.
- Caution must be used in the presence of hepatic impairment
Caspofungin
CONTRAINDICATIONS AND CAUTIONS:
- can be toxic to the liver;
- embryotoxic in animal studies, great caution during pregnancy and lactation
Micafungin
CONTRAINDICATIONS AND CAUTIONS:
should be used during pregnancy and lactation only if the benefits clearly outweigh the risks.
ECHINOCANDIN ANTIFUNGALS
ADVERSE EFFECTS:
- hepatic toxicity
- Potentially serious hypersensitivity reactions
- bone marrow suppression
OTHER ANTIFUNGALS
amphotericin B (Abelcet, AmBisome, Amphotec), fl ucytosine (Ancobon), griseofulvin (generic), and nystatin (Mycostatin, Nilstat).
TOPICAL ANTIFUNGALS Examples:
ketoconazole ( Nizoral,), sertaconazole nitrate (Ertaczo),
sulconazole (Exelderm), terbinafine (Lamisil),
Fungi that cause mycoses
DERMATOPHYTES
mycoses include tinea infections such as
- athlete’s foot (tinea pedis),
- jock itch (tinea cruris),
- yeast infections of the mouth and vagina often caused by
Candida
work to alter the cell permeability of the fungus, causing prevention of replica and fungal death
TOPICAL ANTIFUNGALS
TOPICAL ANTIFUNGALS
PHARMACOKINETIC
These drugs are not absorbed systemically and do not undergo metabolism or excretion in the body.
TOPICAL ANTIFUNGALS
CONTRAINDICATIONS AND CAUTIONS
contraindications are limited to a known allergy to any of these drugs and open lesions
TOPICAL ANTIFUNGALS
ADVERSE EFFECTS
local effects include irritation, burning, rash, and swelling
single-celled organisms that pass through several stages in their life cycles
Protozoa
thrive in tropical climates, but may also survive and reproduce in any area where people live in very crowded and unsanitary conditions.
Protozoa
protozoal infections that can be caused by insect bites:
malaria
trypanosomiasis
leishmaniasis)
protozoal infections that result from ingestion
amebiasis
giardiasis
trichomoniasis
is a parasitic disease through the bite of a female Anopheles mosquito, an insect that harbors the protozoal parasite
MALARIA
FOUR PROTOZOAL PARASITES:
- Plasmodium falciparum
- Plasmodium vivax
- Plasmodium malariae
- Plasmodium ovale
is considered to be the most dangerous type of protozoan.
Plasmodium falciparum
causes a milder form of the disease, which seldom results in
death.
Plasmodium vivax
is endemic in many tropical countries and causes very mild signs and symptoms in the local population
Plasmodium malariae
which is rarely seen, seems to be in the process of being eradicated
Plasmodium ovale
are usually given in com bination form to attack the Plasmodium.
ANTI-MALARIALS
ANTI-MALARIALS drugs can be:
- schizonticidal
- gametocytocidal
- sporontocidal
- schizonts as prophylactic or antirelapse agents