Side effects erythromycin

Buspirone generally is well tolerated and does not cause sedation. Most common side effects include dizziness, nausea, and headaches. Drugs that inhibit CYP3A4 (e.g., verapamil, diltiazem, itraconazole, fluvoxamine, nefa-zodone, and erythromycin) can increase buspirone levels. Likewise, enzyme inducers such as rifampin can reduce buspirone levels significantly. Bupirone may increase blood pressure when coadministered with an monoamine oxidase inhibitor (MAOI). 

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. 

Roxithromycin, clarithromycin, azithromycin and dirithromycin are more recently developed macrolides with similar antimicrobial activity to erythromycin. However they are better absorbed, have longer elimination half-lives and lower incidence of gastrointestinal side-effects. Azithromycin and... 

The incidence of side effects associated with erythromycin therapy is very low. Mild gastrointestinal upset with nausea, diarrhea, and abdominal pain are reported to occur more commonly when the propionate and es-tolate salts are used. Rashes are seen infrequently but may be a part of a general hypersensitivity reaction that includes fever and eosinophilia. Thrombophlebitis may follow intravenous administration, as may transient impairment of hearing. 

Inhibitors of CYP3A4 such as erythromycin, clarithromycin, ketoconazole, itraconazole, ritonavir and grapefruit juice may increase plasma concentrations of estrogens and may result in side effects ... 

Cyclosporin is metabolised by the hepatic cytochrome P-450 enzyme system, and enzyme induction by phenobarbital, phenytoin, carbamazepine, or rifampicin will drastically increase the clearance of cyclosporin. Concurrent administration of these drugs has caused rejection of transplanted organs. Conversely, the use of enzyme inhibitors, such as erythromycin or the azole antifungal agents, e.g. ketoconazole, will increase the blood concentrations of cyclosporin leading to an increased risk of toxic side effects. 

Pharmacokinetics attd Pharmacology. Older macrolides such as erythromycin exhibit relatively low serum concentrations, short in vivo half-hves, highly variable oral absorption, and low oral bioavailability. Improvements in these pharmacokinetic parameters have been accomplished for newer derivatives. The principal side effects of macrolides aie gastrointestinal problems, such as pain, indigestion, diarrhea, nausea, and vomiting. 

Epigastric distress This side effect is common and can lead to poor patient compliance for erythromycin. The new macrolides seem to be better tolerated by the patient gastrointestinal problems are their most common side effects. 

Cholestatic jaundice This side effect occurs, especially with the estolate form of erythromycin, presumably as the result of a hypersensitivity reaction to the estolate form (the lauryl salt of the propionyl ester of erythromycin). It has also been reported for other forms of the drug. 

Although erythromycin is also effective in treating irritable bowel syndrome, its use is limited because of gastrointestinal side effects. 

GALANT AMINE ERYTHROMYCIN t galantamine levels Inhibition of CYP3A4-mediated metabolism of galantamine Be aware watch for t side-effects from galantamine... 

Like erythromycin, the most common side effects of azithromycin and clarithromycin are gastrointestinal, with diarrhea, nausea, and abdominal pain being the most frequently reported. Clarithromycin can also cause headache and dyspepsia. Other side effects of azithromycin include palpitations, vaginitis, headache, dizziness, fatigue, and hypersensitivity reactions. 

Topical corticosteroids are used in cases of exacerbation and should be applied sparingly to the affected area. Hydrocortisone 1% twice a day or dexamethasone 0.1% applied to the periorbital area helps to relieve symptoms during these periods. Secondary infection manifested as blepharitis or keratoconjimctivitis should be treated with topical ophthalmic antibiotic ointments such as bacitracin or erythromycin.Topical antihistamines, NSAIDs, or mast cell stabilizers can be used to control itching, and topical steroids are sometimes required to treat severe keratoconjunctivitis associated with the atopic response. Because of side effects, steroids are not indicated for longterm use. 

A review of 16-membered macrolide antibiotics (Chapter 5) complements a survey of semi-synthetic erythromycins which appeared in Volume 30. Further work in this direction is expected to yield new antibiotics of greater efficiency and a lower level of side-effects. The antibacterial effects of silver have been known for a long time and are assessed in Chapter 7. 

D. Treatment of bacterial infections Antibiotics that selectively affect bacterial function and have minimal side effects in humans are usually selected to treat bacterial infections. Rifampicin, which inhibits the initiation of prokaryotic RNA synthesis, is used to treat tuberculosis. Streptomycin, tetracycline, chloramphenicol, and erythromycin inhibit protein synthesis on prokaiyotic ribosomes and are used for many infections. Chloramphenicol affects mitochondrial ribosomes and must be used with caution. 

Patients presenting with acute erythromycin overdose are usually asymptomatic or experiencing minor to moderate gastrointestinal side effects/ discomfort. Serious cardiac effects, including prolongation of the QT interval, arrhythmias (i.e., ventricular tachycardia. Torsades de Pointes, ventricular fibrillation, and heart block), may be observed after rapid intravenous administration and coincident with high, peak erythromycin plasma concentrations. The occurrences of these QT prolongation-associated arrhythmias are rare. 

Figure 3 Promiscuous HERG channels are blocked by structurally diverse molecules [from (122)]. In addition to compounds developed for K+ channel blockade (Dofetilide and Sotalol), a wide range of compounds, from antihistamines (Terfenadine) to antibiotics (Erythromycin), block HERG as an adverse side effect.

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