Erythromycin dosage

The effects of buspirone are decreased when the drug is administered with fluoxetine Increased serum levels of buspirone occur if the drug is taken with erythromycin or itraconazole Should any of these combinations be required, the dosage of buspirone is decreased to 2.5 mg BID, and the patient is monitored closely. Venlafaxine blood levels increase with a risk of toxicity when administered witii MAOIs or cimetidine There is an increased risk of toxicity when trazodone is administered with the phenothiazines and decreased effectiveness of trazodone when it is administered with carbamazepine Increased serum digoxin levels have occurred when digoxin is administered with trazodone There is a risk for increased phenytoin levels when phenytoin is administered witii trazodone... 

Administration of zafirlukast and aspirin increases plasma levels of zafirlukast, When zafirlukast is administered with warfarin, there is an increased effect of the anti coagulant. Administration of zafirlukast and theophylline or erythromycin may result in a decreased level of zafirlukast. Administration of montelukast with other drugs has not revealed any adverse responses. Administration of montelukast with aspirin and NSAIDs is avoided in patients with known aspirin sensitivity. Administration of zileuton with propranolol increases the activity or the propranolol with theophylline increases serum theophylline levels and with warfarin may increase prothrombin time (PT). A prothrombin blood test should be done regularly in the event dosages of warfarin need to be decreased. 

Erythromycin is considered the optimal drug for treatment of Campylobacter infections. The rate of resistance of Campylobacter to erythromycin remains low. Other advantages of this drug include ease of administration, low cost, lack of major toxicity, and narrow spectrum of activity.14 The recommended dosage for adults is 250 mg orally four times daily or 500 mg orally twice daily for 5 to 7 days. For very ill patients, treatment with gentamicin, imipenem, cefotaxime, or chloramphenicol is indicated, but susceptibility tests should be performed. 

The WHO and CDC recommended treatment regimens are shown in Table 77-5.37 There has been some debate about a suitable dosage of ciprofloxacin in the treatment of chancroid. Though the CDC recommends 500 mg orally three times daily, the WHO supports a single 500-mg oral dose. Ciprofloxacin has demonstrated an acceptable cure rate for a single dose (92%) when compared to erythromycin (91%). 

The U. S. Dispensatory26 reports maximum serum levels of 0.2 ijg./ml. 1 hour after administration of a 250 mg. dose, 0.6 (ig./ml. 2 hours after a 500 mg. dose, and 1.2 ug./ml. 2 hours after a 1 g. dose. Higher blood levels are achieved on a multiple dosage schedule. Since it is acid labile, a resistant coating is used in tablet formulations to overcome the deleterious effect of gastric fluid on erythromycin base or the stearate salt is prepared which does not dissolve readily in the stomach. 

Clarithromycin is a derivative of erythromycin (macrolide). Advantages over erythromycin include lower frequency of gastrointestinal side-effects and lower dosage frequency. Clarithromycin is administered every 12 hours. As with all macrolides it should be used with caution in patients who are at risk of developing QT interval prolongation caused either by electrolyte imbalances or the concomitant use of other drugs. 

Dosage adjustment - Consider a starting dose of 25 mg in the following patients Older than 65 years of age, hepatic impairment, severe renal impairment, and concomitant use of potent cytochrome P450 3A4 inhibitors (eg, erythromycin, ketoconazole, itraconazole, saquinavir). 

Concomitant mecf/caf/ons - The dosage of vardenafil may require adjustment in patients receiving certain CYP3A4 inhibitors. For ritonavir, do not exceed a single dose of 2.5 mg vardenafil in a 72-hour period. For indinavir, ketoconazole 400 mg/day, and itraconazole 400 mg/day, do not exceed a single dose of 2.5 mg vardenafil in a 24-hour period. For ketoconazole 200 mg/day, itraconazole 200 mg/day, and erythromycin, do not exceed a single dose of 5 mg vardenafil in a 24-hour period. 

ERYTHROMYCIN, ORAL Dosages and product strengths are expressed as erythromycin base equivalents (400 mg erythromycin ethylsuccinate produces the same free erythromycin serum levels as 250 mg of erythromycin base, stearate, or estolate). 

Hypertension PO 50 mg once a day. If 50 mg once a day produces an inadequate BP response, may increase dosage to 50 mg twice a day. If patient is concurrently receiving erythromycin, saquinavir, verapamil, or fluconazole, reduce initial dose to 25 mg once a day. 

Dosage with concurrent ketoconazole or itraconazole (at 200 mg/day), or erythromycin ... 

Like fluoxetine, erythromycin and other macrolides inhibit the CYP-3A isoenzyme and increase the levels and effects of the triazolobenzodiazepines (Shader and Greenblatt, 1995 Chouinard et ah, 1999). Midazolam should be avoided or the dosage dropped by 50% in patients receiving erythromycin (Olkkola et ah, 1993). Ketoconazole and itraconazole may also interact with triazolam and midazolam, and combinations of these drugs should be avoided (Varhe et ah, 1994 Chouinard et ah, 1999). 

A 500-mg dose of clarithromycin produces serum concentrations of 2-3 mcg/mL. The longer half-life of clarithromycin (6 hours) compared with erythromycin permits twice-daily dosing. The recommended dosage is 250-500 mg twice daily or 1000 mg of the extended release formulation once daily. Clarithromycin penetrates most tissues well, with concentrations equal to or exceeding serum concentrations. 

Clarithromycin is metabolized in the liver. The major metabolite is 14-hydroxyclarithromycin, which also has antibacterial activity. A portion of active drug and this major metabolite is eliminated in the urine, and dosage reduction (eg, a 500-mg loading dose, then 250 mg once or twice daily) is recommended for patients with creatinine clearances less than 30 mL/min. Clarithromycin has drug interactions similar to those described for erythromycin. 

Erythromycin is a macrolide antibiotic produced by Streptomyces erythreus. It is considered the most active macrolide for treatment of staphylococcal infections in cases of penicillin resistance. It is used parenterally at a dosage of 3-5 mg/kg bw, in intramammary form at 300 mg/quarter, and orally at 20-50 mg/kg bw. For treatment of mycoplasmal infections in poultry, an oral medication... 

A 38-year-old woman who had used inhaled beclo-methasone daily (dosage not stated) during the winter for the past 5 years for mild asthma, developed a perioral rash with numerous small pustules and papules. She stopped using beclomethasone and was treated with oral erythromycin and topical tretinoin. Her rash resolved within 4 weeks. One year later, she restarted beclomethasone and her rash reappeared after 2 weeks. There was no recurrence of her perioral dermatitis during subsequent treatment with monthly intramuscular injections of betamethasone. 

A 46-year-old woman, who had used inhaled budesonide (dosage not stated) for 8 years for vasomotor rhinitis, developed a recurrent perioral rash, which responded to treatment with oral erythromycin 1 g/ day for 6 weeks. One year later, she had a recurrence, which resolved with oral erythromycin. She continued to use inhaled budesonide. 

The oral dosage of erythromycin base, stearate, or estolate is 0.25-0.5 g every 6 hours (for children, 40 mg/kg/d). The dosage of erythromycin ethyl succinate is 0.4-0.6 g every 6 hours. Oral... 

A widely used method to produce multiple-unit dosage forms has been the production of sachets that contain film-coated granules. More common is the use of capsules in which enteric-coated particles are filled. A study that used radioactive tracers revealed that enteric-coated erythromycin pellets in capsules were superior to enteric-coated tablets with respect to faster action of the drug caused by a shorter passage time of the coated granules in the stomach [49-51],... 

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