Antibiotics clarithromycin

Macrolide antibiotics (clarithromycin, dehydroerythromycin, etc.) and sulfonamides (sulfamethoxazole, sulfadimethoxine, sulfamethazine, and sulfathi-azole) are the most prevalent antibiotics found in the environment with levels around a few micrograms per liter, whereas fluoroquinolones, tetracyclines, and penicillins have been detected in fewer cases and usually at low concentrations (nanograms per liter) [3,20,23,72]. This result is not surprising, since penicillins are easily hydrolyzed and tetracyclines readily precipitate with cations such as calcium and are accumulated in sewage sludge or sediments. Several reviews have reported the environmental occurrence of different antibiotics in aquatic and soil compartments. Some of these data are detailed in Table 1. 

Antibiotics clarithromycin, erythromycin Others omeprazole, cisapride, dapsone, lavastatin... 

Macrolide-type antibiotics Clarithromycin, erythromycin, telithromycin, troleandomycin Opioids Alfentanyl, cocaine, fentanyl, sufentanil Steroids Budesonide, cortisol, 17- 3-estradiol, progesterone... 

Among macrolide antibiotics, clarithromycin is effective against M. leprae as an alternative multidrug therapy (MDT) regimen (detailed pharmacology is discussed in Macrolide antibiotics ). 

Nakagawa, Y., Itai, S., Yoshida, T., and Nagai,T. (1992), Physicochemical properties and stability in the acidic solution of a new macrolide antibiotic, clarithromycin, In comparison with erythromycin, Chem. Pharm. Bull., 40,725-728. 

TOLTERODINE ANTIBIOTICS - CLARITHROMYCIN, ERYTHROMYCIN t tolterodine levels Inhibition of CYP3A4-mediated metabolism Avoid co-administration (manufacturers recommendation)... 

MODAFINIL 1. ANTIBIOTICS-clarithromycin, telithromycin 2. ANTIFUNGALS-itraconazole, ketoconazole 3. ANTIVIRALS-indinavir, nelfinavir, ritonavir, saquinavir t plasma concentrations of modafinil, with risk of adverse effects Due to inhibition of CYP3A4, which has a partial role in the metabolism of modafinil Be aware. Warn patients to report dose-related adverse effects, e.g. headache, anxiety... 

IFOSFAMIDE 1. ANTIBIOTICS -clarithromycin, erythromycin 2. ANTIFUNGALS -fluconazole, itraconazole, ketoconazole voriconazole 3. ANTIVIRALS-efavirenz, ritonavir 4. GRAPEFRUIT JUICE 5. H2 RECEPTOR BLOCKERS - cimetidine 1 plasma concentrations of 4-hydroxyifbsfamide, the active metabolite of ifosfamide, and risk of inadequate therapeutic response Due to inhibition of the isoenzymatic conversion to active metabolites Monitor the efficacy of ifosfamide clinically and t dose accordingly... 

GRAPEFRUIT JUICE ANTIBIOTICS - CLARITHROMYCIN, ERYTHROMYCIN Significant delay in onset of action of clarithromycin (t from 82 to 148 minutes), t plasma concentrations of erythromycin (maximum concentration t, AUC 11,5-fbld) Due to inhibition of absorption attributed to effect on P-gp The interaction is unlikely to cause clinically relevant 1 antimicrobial activity of clarithromycin Telithromycin is unlikely to be affected by grapefruit juice. Be aware... 

Pappa-Louisi, A. Papageorgiou, A. Zitrou, A. Sotiro-poulos, S. Georgarakis, E. Zougrou, F. Study on the electrochemical detection of the macrolide antibiotics clarithromycin and roxithromycin in reversed-phase high-performance liquid chromatography. J. Chromatogr. B Biomed. Sci. Appl. 2001, 755, 57-64. 

In addition to being available in a variety of dosage forms as the hydrochloride salt, ranitidine is also available us a bismuth citrate salt for use with the macrolide antibiotic clarithromycin in treating patients with an active duodenal ulcer... 

Macrolide antibiotics (clarithromycin, erythromycin) Azithromycin has no significant interaction with rifamycins. 

IRINOTECAN 1. ANTIBIOTICS-clarithromycin, erythromycin 2. ANTICANCER AND IMMUNOMODULATING DRUGS - imatinib 3. ANTIFUNGALS -fluconazole, itraconazole, ketoconazole, voriconazole 4. ANTIVIRALS-efavirenz, ritonavir 5. GRAPEFRUIT JUICE 6. H2 RECEPTOR BLOCKERS - cimetidine t plasma concentrations of SN-38 (t AUC by 100%) and t toxicity of irinotecan, e.g. diarrhoea, acute cholinergic syndrome, interstitial pulmonary disease Due to inhibition of the metabolism of irinotecan by CYP3A4 isoenzymes by ketoconazole Peripheral blood counts should be checked before each course of treatment. Monitor lung function. Recommendation is to -L dose of irinotecan by 25%... 

H. pylori is a major etiological factor in gastroduodenal disorders such as chronic gastritis, peptic ulcer, and gastric cancer. Therefore, the treatment and prevention of these diseases would be facilitated by its eradication. At present, triple therapies that comprise two antibiotics (clarithromycin and amphotericin B) and a proton pump inhibitor are used to eradicate H. pylori. However, strains that are resistant to antibiotics have appeared. In addition, antibiotic treatment is associated with serious side effects such as nausea, vomiting, and diarrhea. Therefore, the discovery of novel antibacterial agents that are highly effective and safe is badly needed for the treatment of H. pylori infection. 

Vatsraj S, Chauhan K, Pathak H. Formulation of a novel nanoemulsion system for enhanced solubility of a sparingly water soluble antibiotic, clarithromycin. Journal of Nanoscience. 2014 2014 268293. 

Among the related substances in many antibiotics are various structurally related components in the drug substance, the composite mixture of which is obtained in the synthetic or semisynthetic scheme and which gives rise to the drug efficacy. Control of the relative content of components is therefore necessary for these drugs. Test specification limits for the components are normally stated in terms of area percent of each, as maximum, minimum or a range of values for each or for the sums of several components. The types of components seen in these antibiotics were studied as impurities in the semisynthetic antibiotic clarithromycin, where detection limits of 0.1% w/w were found. Normalization factors were determined for each of 15 known related substances using ratios of the slope of linear calibrations for each substance to that for the reference impurity. 

A desired loss in resolution was the driving force in a recent study on the macrohde antibiotic clarithromycin 7 at 400 MHz [89]. A H—H TOCSY sequence with a Zangger—Sterk module [90] for suppressing homonuclear J-evolution in the indirect dimension formed the basis for a doubly pure-shift TOCSY. The Fourier transform in the direct dimension was followed... 

The broad-spectrum macroUde antibiotic clarithromycin (Fig. 5.6) has been shown to form hepatic CYP3A -MI complexes when administered to control or dexamethasone (DEX)-pretreated rats [229, 260]. In vitro studies with DEX-pre-treated rat fiver microsomes (enriched in CYP3 A... 

The macrolide antibiotics clarithromycin (and its metabolite 14-hydroxyclari-thiomycin) and azithromycin (roxithromycin internal standard) were isolated from plasma and quantitated on a cyanopropyl column (electrochemical detection at +0.85 V). Azithromycin was eluted in 12 min with a 500/600/50 water (50 mM phosphate at pH 6.8)/acetonitrile/methanol mobile phase [1345]. The clarithiomy-cins were separated and eluted m 20 min with a 450/300/50 water (50 mM phosphate at pH 7.5)/acetonitrile/methanol mobile phase. The authors noted that phosphate buffers were chosen over ammonium buffers because the background noise was considerably higher with the latter. Linear ranges in the 0.025-5 pg/mL range and detection limits of 0.5-1.5 ng injected (S/N = 3) were reported (analyte dependent). 

If the phenomenon of nonporous solid-state diffusion can occur with calixarenes, the implication is that it can also occur with many other materials. A recent article by Atwood and coworkers reported the transport of water and CO2 molecules within seemingly nonporous crystals of the antibiotic clarithromycin (6-O-methylerythromycin A, 4, Figure 17a). Crystals of pure guest-free 4 were... 

The epoxide metabolite is believed to exhibit activity similar to that of the parent compound and therefore contributes substantially to the overall therapeutic effects of carbamazepine. This feet must be taken into consideration when a patient is taking other medications. For instance, the antibiotic clarithromycin has been found to inhibit the action of the enzyme epoxide hydroxylase. This causes the concentration of the epoxide to be higher than normal, increasing the potency of carbamazepine. Before a physician prescribes carbamazepine for a patient, potential drug interactions must be taken into account This is an example of one important factor that practicing physicians must consider—specifically, the effect that one drug can have on the potency of another drug. 

The two antibiotics with which PPIs synergize are amoxicillin and clarithromycin. The former antibiotic inhibits cell wall biosynthesis by inhibiting peptidyl transferase and by binding to other proteins in the cell wall biosynthesis pathways. Cell division is therefore required for the bactericidal action of this class of antibiotic. Clarithromycin binds to the 23S RNA and thereby inhibits protein synthesis. Hence, protein synthesis is required for the action of this antibiotic. Metronidazole is reduced to the hydroxylamine derivative, which then binds to DMA, hence not requiring cell division or protein synthesis for its efficacy. PPIs do not synergize with this antibiotic. Resistance to metronidazole develops by decrease of the level of reducing enzyme and, therefore, may be relative or absolute. Resistance to clarithromycin occurs by a base mutation at the binding site on the RNA and is usually absolute. 

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