Gastrointestinal tract infections, treatment

As with all drugs, the specific side effects of the quinolones must be considered when they are chosen for treatment of bacterial infections [5]. Reactions of the gastrointestinal tract and the central neivous system are the most often observed adverse effects during therapy with quinolones. It should be underlined, however, that compared with many other antimicrobials, diarrhea is less frequently observed during quinolone treatment. Antibiotic-associated colitis has been observed rarely during quinolone therapy. Similarly, hypersensitivity reactions, as observed during therapy with penicillins and other (3-lactams, is less frequently caused by quinolones. Some other risks of quinolone therapy have been defined and must be considered if a drug from this class is chosen for treatment of bacterial infections. 

In severe cases, or those refractory to treatment, truncal and limb weakness may be accompanied by involvement of masticatory, bulbar, and respiratory muscles. However the most life-threatening clinical manifestations are those affecting the gastrointestinal tract, since stomach ulceration can occur and death from perforation and peritonitis are not unknown. Medication with steroidal antiinflammatory agents is necessary but weakens the childrens resistance to infection, so that systemic spread of usually self-limiting disorders, such as candidiasis, may occasionally occur. 

Nystatin has a specific action on C. albicans and is of no value in the treatment of any other type of infection. It is poorly absorbed from the gastrointestinal tract even after very large doses, the blood level is insignificant. It is administered orally in the treatment of oral thrush and intestinal candidiasis infections. 

Yamashita reported anti-inflammatory effect of astaxanthin when administered with aspirin. An oral preparation has been developed by Alejung and Wadstroem for the treatment of Helicobacter infections of the mammalian gastrointestinal tract. Strong evidence suggested that astaxanthin modulated the humoral and non-humoral immune systems. It enhanced the release of interleukin-1 and tumor necrosis factor-... 

Enterococcus species are normal inhabitants of the gastrointestinal tract, but should empiric treatment of intra-abdominal infections have activity against Enterococcus species Empiric treatment that covered Enterococcus species in intraabdominal infections was equivalent to empiric treatment that lacked enterococcal coverage. Routine coverage for Enterococcus is not necessary for patients with community-acquired intra-abdominal infections. However, in patients with nosocomial or high-severity infections, enterococcal coverage may be warranted.39... 

Enterotoxigenic E. coli (ETEC) is the main cause of TD in Latin America, whereas in Asia it is reported in only 15% of cases. Enteroinvasive E. coli (EIEC) strains are recorded with even less frequency. ETEC is isolated in 0 to 5% of cases. Symptoms of poisoning develop after 16 hours from consumption of contaminated water, salads, cheeses, or meats. The outgrowth of ETEC rods takes place in a patient s gastrointestinal tract, where they produce thermostable and thermolabile toxins that imitate Vibrio cholerae infections. Stimulation of intestinal guanylcyclase and interruption of ion transport leads to watery stools, which do not require medical treatment or only need simple replacement of fluids and salts by means of multielectrolyte solutions. If a co-infection with EIEC strains occurs, the symptoms of enteritis will develop, with the presence of leukocytes, erythrocytes, and mucous in stools due to a cytotoxic influence of bacteria (Butterton and Claderwood, 2001). 

It is poorly absorbed from the gastrointestinal tract and is therefore mainly useful for treatment of luminal intestinal infections. It is mainly excreted unchanged in faeces and not more than 15% of the dose is excreted in the urine, either as unchanged drug or in the form of metabolites. 

Topical formulations of nystatin and of amphotericin B are useful in the management of Candida albicans infections of the skin. Both antibiotics are ineffective against dermatophytes. The use of nystatin is limited to topical treatment of cutaneous and mucosal Candida infections because of its narrow spectrum and its negligible absorption from the gastrointestinal tract. Hypersensitivity reactions are rare. It is not known whether topical nystatin can cause fetal harm when used by a pregnant woman. Amphotericin B has broader antifungal activity but its topical use is restricted to Candida. Topical use of amphotericin B has shown minimal absorption through the skin and is well tolerated. Limited human surveillance data do not indicate any harm to mother or fetus, but relative safety is still unknown. 

It is used in the treatment of infection of gastrointestinal and respiratory tract, skin and soft tissue infections, septicaemia and urinary tract infection. 

This antibiotic is used as an economical oral treatment for gram-positive infections in farm animals at a dosage of 8 mg/kg bw because it has the property of being stable in the gastric acid, allowing it to be bioavailable by the oral route. It is well absorbed from the gastrointestinal tract and metabolized in the liver. Unchanged compound and metabolites are excreted in urine. Small amounts are also found in bile. 

Baquiloprim is a diaminopyrimidine derivative acting synergistically with sulfonamides (221). In cattle, it is used orally, intravenously, or intramuscularly for treatment of mastitis and infections of the respiratory and gastrointestinal tract, whereas, in swine, it is administered intramuscularly for treatment of the mastitis-metritis-agalactia syndrome and infections of the respiratory and gastrointestinal tract. 

Nystatin [nye STAT in] is a polyene antibiotic its structure, chemistry, mode of action, and resistance resemble those of amphotericin B. Its use is restricted to topical treatment of Candida infections because of its systemic toxicity. The drug is negligibly absorbed from the gastrointestinal tract, and it is never used par-enterally. It is administered as an oral agent ( swish and swallow ) for the treatment of oral candidiasis. Excretion in the feces is nearly quantitative. Adverse effects are rare because of its lack of absorption, but occasionally nausea and vomiting occur. 

The breakthrough in the development of quinolones came with the appearance of norfloxacin 6 [19], a second-generation quinolone which combined a 6-fluorine substituent with a piperazine ring in the 7-position of the basic compound. Additional quinolones then followed in rapid succession pefloxacin [20], enoxacin [21] and fleroxacin [22] (Fig. 14.5). Particular mention must be made of ciprofloxacin 8 [23-25], ofloxacin 5 [26,27] and its active enantiomer levofloxacin 7 [28]. These quinolones have a broad spectrum of activity, which also includes Gram-positive bacteria and Pseudomonas aeruginosa, as well as favorable pharmacokinetics. The rapid absorption of these compounds from the gastrointestinal tract and their effective tissue penetration also allows them to be used for the treatment of systemic infections. 

Sulfonamides maintain a significant role even today, because they are often used in combination with other antibacterials. For example, trimethyoprim, 35, has a diaminopyrimidine structure that has proved to be a highly selective, orally active, antibacterial, and antimalarial agent [6]. Trimethyoprim is combined to sulfamethoxazole, 36, for the treatment of bacterial respiratory tract infections and gastrointestinal infections [9]. 

Amantadine is effective only against influenza A it acts by interfering with the uncoating and release of viral genome into the host cell. It is well absorbed from the gastrointestinal tract and is eliminated in the mine 3 h). Amantadine may be used orally for the prevention and treatment of infection with influenza A (but not influenza B) virus. Those most likely to benefit include the debilitated, persons with respiratory disability and people living in crowded conditions, especially during an influenza epidemic. 

Terbinafine interferes with ergosterol biosynthesis, and thereby with the formation of the fungal cell membrane. It is absorbed from the gastrointestinal tract and undergoes extensive metabolism in the liver (tj 14 h). Terbinafine is used topically for dermatophyte infections of the skin and orally for infections of hair and nails where the site (e.g. hair), severity or extent of the infection render topical use inappropriate (see p. 315). Treatment (250 mg/d) may need to continue for several weeks. It may cause nausea, diarrhoea, dyspepsia, abdominal pain, headaches and cutaneous reactions. 

After almost complete absorption from the gastrointestinal tract, nitrofurantoin produces high urinary concentrations. Blood and tissue concentrations are low. Nitrofurantoin has been used almost exclusively in the treatment and prophylaxis of urinary tract infections (1). Because of the severity of its adverse effects it should not be used as first choice. 

Vancomycin is particularly useful in infections caused by meticillin-resistant or penicillinase-producing staphylococci and diphtheroids, as well as in the prophylaxis of bacterial endocarditis and in the treatment of antibiotic-associated colitis. Sufficient fecal concentrations can be achieved with oral therapy. It is poorly absorbed from the gastrointestinal tract and painful when injected intramuscularly. It diffuses moderately well into bone tissue (6). 

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