Miscellaneous Antimicrobial Agents 50 Flashcards
a nitroimidazole antiprotozoal drug that also has potent antibacterial activity against anaerobes, including Bacteroides and Clostridium species. It is selectively absorbed by anaerobic bacteria and sensitive protozoa
Metronidazole
Is indicated for treatment of anaerobic or mixed intro-abdominal infections, vaginitis, clostridium difficile infection and brain abscess.
Metronidazole
A structurally similar agent to metronidazole that is taken once-daily for treatment of trichomonas infection, giardiasis, amebiasis and bacterial vaginosis
Tinidazole
a narrow-spectrum, macrocyclic antibiotic that is active against Gram-positive aerobes and anaerobes but lacks activity against Gram-negative bacteria.
Fidaxomicin
Inhibits bacterial protein synthesis by binding to the sigma subunit of RNA polymerase
Fidaxomicin
Has been approved by the FDA for the treatment of C difficile infection
It is effective as oral vancomycin and may be associated with lower rates of relapsing disease
Fidaxomicin
a derivative of rifampin. It is active against Gram- positive and Gram-negative aerobes and anaerobes
Rifaximin
inhibits bacterial protein synthesis by binding to the beta sub- unit of DNA-dependent RNA polymerase.
Rifaximin
__ was originally approved by the FDA for the treatment of travelers’ diarrhea, and it is now used in the management of hepatic encephalopathy, irritable bowel syndrome with diarrhea, and, occasionally, as an adjunct in case of recurrent or refractory C difficile infection in adults
Rifaximin
(pseudomonic acid) is a natural substance produced by Pseudomonas fluorescens. It is available as an ointment for topical application
Mupirocin
inhibits staphylococcal isoleucyl tRNA synthetase
Mupirocin
____ is indicated for topical treatment of minor skin infections such as impetigo
Mupirocin
group of basic peptides active against Gram- negative bacteria and include polymyxin B and polymyxin E (colistin).
Polymyxins
act as cationic detergents. They attach to and disrupt bacterial cell membranes. They also bind and inacti- vate endotoxin.
Polymyxins
Are oral agents that exert antibacterial activity in the urine but have little or no systemic antibacterial effect
Urinary antiseptics
Antibacterial activity appears to correlate with rapid intracellular conversion of ______ to highly reactive inter- mediates by bacterial reductases. These intermediates react non- specifically with many ribosomal proteins and disrupt metabolic processes and the synthesis of proteins, RNA, and DNA
Nitrofurantoin
Dosage of nitrofurantoin for UTI is?
100mg orally / 4 times daily
This drug should not be used to treat upper urinary tract infections. It is desirable to keep urinary pH below 5.5, which greatly enhances drug activity.
Nitrofurantoin
Is the salt of mandelic acid and methenamine and possesses properties of both urinary antiseptics
Methenamine mandelate
is the sale of hippuric acd and methenamine.
Methenamine hippurate
Below pH 5.5, methenamine releases ______ which is antibacterial
Formaldehyde
Methenamine ____, 1g four times daily, or methenamine _____, 1g twice daily by mouth is used only AS A URINARY ANTISEPTIC TO PREVENT, NOT TREAT, asymptomatic urinary tract infections
Mandelate
Hippurate
Methenamine mandelate, 1 g four times daily, or methenamine hippurate, 1 g twice daily by mouth is used only as a urinary antiseptic to prevent, not treat, _____
Symptomatic urinary tract infections
are chemical agents or physical procedures that inhibit or kill microorganisms
Disinfectants
are dis- infecting chemical agents with sufficiently low toxicity for host cells that they can be used directly on skin, mucous membranes, or wounds.
Antiseptics
kill both vegetative cells and spores when applied to materials for appropriate times and temperatures
Sterilants
Prevents infections by reducing the number of potentially infective organisms by killing, removing or diluting them.
Disinfections
_______ can be accomplished by application of chemi- cal agents or use of physical agents such as ionizing radiation, dry or moist heat, or superheated steam (autoclave, 120°C) to kill microorganisms.
Disinfection
the most important means of pre- venting transmission of infectious agents from person to person or from regions of high microbial load, eg, mouth, nose, or gut, to potential sites of infection.
Hang hygiene
What are the two most frequently used alcohols or antisepsis and disinfection
Enthanol and isopropyl alcohol (isopropanol)
Alcohols rapidly kill?
Vegetative bacteria, mycobacterium,TB and many fungi
Application of an agent to living tissue for the purpose of preventing infection
Antisepsis
Process that produces marked reduction in number of activity of microorganisms
Decontamination
Chemical or physical treatment that destroys most vegetative microbes and viruses, but not spores, in or on inaminate surfaces
Disinfection
Reduction of microbial load on an inanimate surface to a level considered acceptable or public health purposes
Sanitization
A process intended to kill or remove all types of microorganisms, including spored, and usually viruses, with an acceptably low probability of their survival
Sterilization
A process that kills nonsporulating microorganism by how water or steam at 65-100C
Pasteurization
a cationic biguanide with very low water solubility.
Chlorhexidine
in a 1:20,000 solution is bactericidal in 1 minute and kills spores in 15 minutes.
It is the most active antiseptics for intact skin
Iodine
Are complexes of iodine with a surface-active agent such as polyvinyl pyrrolidone (PVP; povidone-iodine). Can be used as antiseptics or disinfectants
They are less irritating and less likely o produce skin hypersensitivity than tincture of iodine
Iodophors
a strong oxidizing agent and universal disinfectant that is commonly provided as a 5.25% sodium hypochlorite solution, a typical formulation for household bleach.
Chlorine
Alternative chlorine releasing compounds
Chlorine dioxide and chloramine-T
( The oldest of the surgical antiseptics) is no longer used even as a disinfectant because of its corrosive effect on tissue
Phenol
bactericidal action of ________ has been attributed to inactivation of energy-producing enzymes, denaturation of proteins, and disruption of the cell membrane
Quaternary compounds
bind to the surface of colloidal protein in blood, serum, and milk and to the fibers in cotton, mops, cloths, and paper towels used to apply them, which can cause inactivation of the agent by removing it from solution.
Quaternary ammonium compounds
What inhibits quaternary ammonium compounds?
Soaps, nonionic detergents, calcium, magnesium, ferric and aluminum ions
used for disinfection or sterilization of instruments such as fiberoptic endoscopes, respira- tory therapy equipment, hemodialyzers, and dental instruments that cannot withstand exposure to the high temperatures of steam sterilization.
Formaldehyde and glutaraldehyde
A potential carcinogen and has established an employee exposure standard that limits the 8-hour time weighted average exposure to 0.75ppm
Formaldehyde
a phenolic dialdehyde chemi- cal sterilant with a spectrum of activity comparable to glutaralde- hyde, although it is several times more rapidly bactericidal.
Ortho-phthalaldehyde (OPA)
basic method for sterilizing instruments and other heat-resistant materials.
pressurized steam (autoclaving) at 120°C for 30 minutes
are used as preservatives to prevent the over- growth of bacteria and fungi in pharmaceutical products, laboratory sera and reagents, cosmetic products, and contact lenses.
Disinfectants
Commonly used preservative agents include organic acids such as?
Benzoic acid and salts, parabens, sorbic acid and salts phenolic compounds, quater- nary ammonium compounds, alcohols, and mercurials
