Antibacterial drug tetracyclines

This example illustrates that clearance is actually the amount of plasma that the drug can be totally removed from per unit time. As calculated here, the liver would be able to completely remove aspirin from 495 mL of blood each minute. Tetracycline, a common antibacterial drug, has a clearance equal to 130 mL/min, indicating that this drug would be completely removed from approximately 130 mL of plasma each minute. 

Antibacterial drugs that affect bacterial protein synthesis include the aminoglycosides, tetracyclines, macrolides, and the single drug chloramphenicol. 

Bubonic plague no longer causes the great dread that it once did, because there are now several very effective antibacterial drugs that can destroy the bacillus. These include streptomycin, chloramphenicol and the tetracyclines, but not the penicillins or related drugs. Nonetheless, the sheer scale of the loss of life in the pre-antibiotic era provides a timely reminder of how much we have grown to depend upon these magic bullets . 

Antibacterial drugs that inhibit protein synthesis aminoglycosides, tetracyclines, macrolldes and chloramphenicol... 

The discovery of a novel structural class of antibacterials is notable, as these are few and far between. The sulfa drugs, p-lactams, quinohnes, tetracyclines, macrohdes, and aminoglycosides have been around for decades. Multiple improvements have been made over time in each of these classes but without breaking out into new structural classes. There are two notable, recent examples of new stractural classes of antibacterials and these are worth knowing about. 

The quinolone antibiotics feature as the one main gronp of antibacterial agents that is totally synthetic, and not derived from or based upon natural products, as are penicillins, cephalosporins, macrolides, tetracyclines, and aminoglycosides. The first of these compounds to be employed clinically was nalidixic acid more recent drugs in current use include ciprofloxacin, norfloxacin, and ofloxacin... 

In terms of antibacterial spectrum, this drug is similar to chlorotetracycline. It is used for the same indications. It belongs to the group of short-lasting tetracyclines. Synonyms of this drug are tetramycin, oxymycin, and others. 

Some drugs, including sulfaquinoxaline, sulfadimethoxine, sulfame-thoxypyridazine, sulfachlorpyrazine, sulfamethazine, sulfaguanidine, furazolidone, nitrofurazone, tetracycline, and chlortetracycline, in addition to their role as coccidiostats, are also used as antibacterials. These drugs will not be discussed in this chapter since they have been discussed previously. On the other hand, other compounds such as roxarsone, are classified as growth promoters and therefore will be described in the corresponding chapter. This chapter is limited to compounds whose primary function and use are as antiprotozoals. 

Treatment of H. pylori infection typically consists of a combination therapy, using several drugs simultaneously.42 For example, one common form of triple therapy consists of two antibacterials (amoxicillin and clarithromycin) and one of the PPIs described earlier in this chapter.17 36 Alternatively, various quadruple therapies have been used combining bismuth compound (described later in the section on Treatment of Diarrhea ) with a PPI and two antibacterials (e.g., tetracycline and metronidazole).5,36 These drug regimens are typically administered for 1 to 2 weeks and... 

Finally, it has to be noted that glycopeptides only represent one option to combat infections by gram-positive bacteria. Current research is focused on other cell wall biosynthesis inhibitors (e.g., (3-lactams, cephalosporins) or even on the development of antibacterial agents (e.g., tetracyclines, ketohdes, and quinolone antibiotics) against other targets.An important drug candidate in this context is hnezolid (Zyvox), which is an entirely synthetic oxazolidinone antibiotic with in vitro and in vivo efficiency against MRS A and VRE. ... 

Finally we mention the tetracyclines, which are derivatives of the fonr-ring aromatic compound represented in Figure 7.33c. These drugs have the broadest spectrum of antibacterial activity found to date. 

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