Bacteriostatic antibiotics

Holy thistle is believed to have bitter stomachic, antidiarrheal, antihemorrhagic, febrifuge, expectorant, antibiotic, bacteriostatic, vulnerary, and antiseptic properties. Traditionally, it has been used for anorexia, flatulent dyspepsia, bronchial catarrh, topically for gangrenous and indolent ulcers, and specifically for atonic dyspepsia and enteropathy with flatulent colic. 

Lincosamide antibiotic bacteriostatic inhibitor of protein synthesis (50S) active against gram-positive cocci, B fragilis. Tox GI distress, pseudomembranous colitis. 

There are two types of antibiotics bacteriostatic and bacteriocidal. Bacteriostatic antibiotics stop bacteria from growing inside the body. Bacteriocidal antibiotics kill bacteria. 

Products and Uses A germicide or fungicide used as an antibiotic, bacteriostat, and antifungal. Precautions Harmless when used for intended effect. 

P-lactam antibiotics, exert thek antibacterial effect by interfering with the synthesis of the bacterial cell wall. These antibiotics tend to be "kreversible" inhibitors of cell wall biosynthesis and they are usually bactericidal at concentrations close to thek bacteriostatic levels. Cephalospotins are widely used for treating bacterial infections. They are highly effective antibiotics and have low toxicity. 

It has been known for some time that tetracyclines are accumulated by bacteria and prevent bacterial protein synthesis (Fig. 4). Furthermore, inhibition of protein synthesis is responsible for the bacteriostatic effect (85). Inhibition of protein synthesis results primarily from dismption of codon-anticodon interaction between tRNA and mRNA so that binding of aminoacyl-tRNA to the ribosomal acceptor (A) site is prevented (85). The precise mechanism is not understood. However, inhibition is likely to result from interaction of the tetracyclines with the 30S ribosomal subunit because these antibiotics are known to bind strongly to a single site on the 30S subunit (85). 

Topical antibiotics exert a direct local effect on specific microorganisms and may be bactericidal or bacteriostatic. Bacitracin (Baciguent) inhibits the cell wall synthesis. Bacitracin, gentamicin (G-myticin), erythromycin (Emgel), and neomycin are examples of topical antibiotics. These drugp are used to prevent superficial infections in minor cuts, wounds, skin abrasions, and minor burns. Erythromycin is also indicated for treatment of acne vulgaris. 

Antibiotics possess antibacterial activity and are used in the treatment of eye infections. Sulfonamides possess a bacteriostatic effect against a wide range of gram-positive and gram-negative microorganisms. They are used in the treatment of conjunctivitis, comeal ulcer, and other superficial infections of the eye. See the Summary Drug Table Select Ophthalmic Preparations and Chapter 6 for additional information on the sulfonamides. 

Studies to elucidate the mode of bacteriostatic property of xanthostatin (XS), a novel depsipeptide antibiotic with an A/-acetylglydne side chain and selective antimicrobial activity against Xanthomonas spp., were carried ont by Kim and coworkers [80]. Two biotransformed XSs were isolated by the treatment of XS with the cell... 

The application of various antibiotics such as rifampicin/tetracycline (63), cefatoxime/trimethoprim (64), or bacteriostatic compounds such as Micropur (Roth, Karlsruhe, Germany) (65) used for root pretreatment or added to collection media is another strategy to prevent biodegradation during root exudate collection. However, depending on dosage and plant species, also phytotoxic effects of antibiotics have been reported (Table 3). Antibiotics in the soil environment... 

Antimicrobials also can be classified as possessing bactericidal or bacteriostatic activity in vitro. Bactericidal antibiotics generally kill at least 99.9% (3 log reduction) of a bacterial population, whereas bacteriostatic antibiotics possess antimicrobial activity but reduce bacterial load by less than 3 logs. Clinically, bactericidal antibiotics may be necessary to achieve success in infections such as endocarditis or meningitis. A full discussion of the application of antimicrobial pharmacodynamics is beyond the scope of this chapter, but excellent sources of information are available.15... 

Doxycyline is a tetracycline antibiotic. All tetracylines are bacteriostatic, have a broad spectrum and are the treatment of choice for infections caused by Chlamydia and Rickettsia and in brucellosis. Doxycyline and minocyline are the only two tetracyclines that may be administered in renal impairment. 

Antibiotics have either cidal (killing) effect or a static (inhibitoiy) effect on microbes. A few examples of the two types of antibiotics are as follows Bactericidal Bacteriostatic... 

In many therapeutic situations the drug combinations are completely misused (12). Adding another drug to a combination does not reduce the need for sound clinical judgement in therapy. Although there are many disease situations in which the use of more than one antibacterial agent may be justified, generalizations about various combinations of bactericidal or bacteriostatic antibiotics or admixtures have not proven valid. Basically, antibiotic combinations should be avoided as a common practice unless they have shown a clear increase in effectiveness as reported in the literature. 

Macrolides, lincosamides and streptogramins are protein biosynthesis inhibitors that bind to 50S subunit of the ribosome and inhibit peptidyl tRNA translocation from the A-site to the P-site." Macrolides have a glycosylated 14-, 15- or 16-membered lactone ring structure and are produced by several species of Streptomyces. Lincosamide antibiotics were isolated initially from Streptomyces lincolnensis but later isolated from different species of Streptomcyces. Streptogramins were also isolated from Streptomycesgraminofaciens and subsequently from several different Streptomyces species. There are two structurally different streptogramins, A and B they are bacteriostatic individually and can be bactericidal when combined. 

Erythromycin inhibits bacterial protein synthesis by reversibly binding with their 50 S ribosomal subunit, thus blocking the formation of new peptide bonds. Erythromycin is classified as a bacteriostatic antibiotic. 

Lincosamides (lincomycin and clindamycin) are representatives of a very small group of drugs synthesized up of an amino acid bound to an amino sugar. Lincosamides bind with the 50 S ribosomal subunit of bacteria and inhibit protein synthesis. They also inhibit pep-tidyltransferase action. Lincosamides are bacteriostatic antibiotics however, when they reach a certain level in the plasma, they also exhibit bactericidal action against some bacteria. Lincosamides are highly active against anaerobic infections such as Peptococcus, Peptostreptococcus, Actinomyces, Propionibacterium, and Clostridium fringens, a few types of Peptococcus and Clostridium. 

Pharmacology Macrolide antibiotics reversibly bind to the P site of the SOS ribosomal subunit of susceptible organisms and inhibit RNA-dependent protein synthesis. They may be bacteriostatic or bactericidal, depending on such factors as drug concentration. 

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