Romed

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What other drugs will affect Romed?

Romed has a much lower affinity for cytochrome P450 than erythromycin, and consequently has fewer interactions. Interactions may be observed, however, with drugs that bind to alpha-1-acid glycoprotein, e.g. disopyramide. Romed does not appear to interact with oral contraceptives, prednisolone, carbamazepine, ranitidine or antacids. Theophylline. A study in normal subjects concurrently administered Romed and theophylline has shown some increase in the plasma concentration of the latter. While a change in dosage is usually not required, patients with high levels of theophylline at commencement of treatment should have levels monitored. Ergot alkaloids. Reactions of ergotism with possible peripheral necrosis have been reported after concomitant therapy of macrolides with vasoconstrictive ergot alkaloids, particularly ergotamine and dihydroergotamine. Because a clinical interaction with Romed cannot be excluded, administration of Romed to patients taking ergot alkaloids is contraindicated. Disopyramide. An in vitro study has shown that Romed can displace protein bound disopyramide; such an effect in vivo could result in increased serum levels of disopyramide. Consequently, ECG and, if possible, disopyramide serum levels should be monitored. Terfenadine. Some macrolide antibiotics (e.g. erythromycin) may increase serum levels of terfenadine. This can result in severe cardiovascular adverse events, including QT prolongation, torsades de pointes and other ventricular arrhythmias. Such a reaction has not been documented with Romed, which has a much lower affinity for cytochrome P450 than erythromycin. However, in the absence of a systematic interaction study, concomitant administration of Romed and terfenadine is not recommended. Astemizole, cisapride, pimozide. Other drugs, such as astemizole, cisapride or pimozide, which are metabolised by the hepatic isozyme CYP3A4, have been associated with QT interval prolongation and/or cardiac arrhythmias (typically torsades de pointes) as a result of an increase in their serum level subsequent to interaction with significant inhibitors of this isozyme, including some macrolide antibacterials. Although Romed has no or limited ability to complex CYP3A4 and hence to inhibit the metabolism of other drugs processed by this isozyme, a potential for clinical interaction of Romed with the above mentioned drugs cannot be either ascertained or ruled out in confidence. Thus, concomitant administration of Romed and such drugs is not recommended. Warfarin. While no interaction was observed in volunteer studies, Romed appears to interact with warfarin. Increases in prothrombin time (international normalised ratio (INR)) have been reported in patients treated concomitantly with Romed and warfarin or the related vitamin K antagonist phenprocoumon, and severe bleeding episodes have occurred as a consequence. Digoxin and other cardiac glycosides. A study in healthy volunteers has shown that Romed may increase the absorption of digoxin. This effect, common to other macrolides, may very rarely result in cardiac glycoside toxicity. This may be manifested by symptoms such as nausea, vomiting, diarrhoea, headache or dizziness. Cardiac glycoside toxicity may also elicit heart conduction and/or rhythm disorders. Consequently, in patients treated with Romed and digoxin or another cardiac glycoside, ECG and, if possible, the serum level of the cardiac glycoside should be monitored. This is mandatory if symptoms suggesting cardiac glycoside overdosage have occurred. Midazolam. Romed, like other macrolides, may increase the area under the midazolam concentration-time curve and the midazolam half-life. Thus, the effects of midazolam may be enhanced and prolonged in patients treated with Romed. There is no conclusive evidence for an interaction between Romed and triazolam. Cyclosporin. A slight increase in plasma concentrations of cyclosporin A has been observed. This does not generally necessitate altering the usual dosage.