Roxithromycin Carbamazepine

Stuer et al. [46] evaluated the presence of the 25 most used pharmaceuticals in the primary health sector in Denmark (e.g., paracetamol, acetyl salicylic acid, diazepam, and ibuprofen). They compared PECs with experimental determinations and they conclude that measured concentrations were in general within a factor of 2-5 of PECs. Carballa et al. [45] also determined PECs for pharmaceuticals (17), musk fragrances (2) and hormones (2) in sewage sludge matrix. For that purpose they used three different approaches (1) extrapolation of the per capita use in Europe to the number of Spanish inhabitants for musk fragrances (2) annual prescription items multiplied by the average daily dose for pharmaceuticals and (3) excretion rates of different groups of population for hormones. They indicated that these PECs fitted with the measured values for half of them (carbamazepine, diazepam, ibuprofen, naproxen, diclofenac, sulfamethoxazole, roxithromycin, erythromycin, and 17a-ethiny I e strad iol). 

Roxithromycin did not alter the pharmacokinetics of carbamazepine (15) or interact with warfarin, ranitidine, or antacids containing hydroxides of aluminium and magnesium (1). 

Saint-Salvi B, Tremblay D, Surjus A, Lefebvre MA. A study of the interaction of roxithromycin with theophylline and carbamazepine. J Antimicrob Chemother 1987 20(Suppl B) 121-9. 

Clinically important, potentially hazardous interactions with amprenavir, aprepitant, atazanavir, carbamazepine, chlorpheniramine, cimetidine, clarithromycin, clorazepate, CNS depressants, darunavir, delavirdine, dexamethasone, efavirenz, erythromycin, esomeprazole, fluconazole, fluoxetine, fosamprenavir, grapefruit juice, griseofulvin, imatinib, indinavir, itraconazole, ivermectin, ketoconazole, lopinavir, nelfinavir, nevirapine, phenobarbital, phenytoin, primidone, rifabutin, rifampin, ritonavir, roxithromycin, saquinavir, St John s wort, telithromycin, tipranavir... 

Carbamazepine serum levels are markedly and rapidly increased by eiythromycin or troleandomycin, and toxicity can often develop within 1 to 3 days. Telithromycin is predicted to interact similarly. Clarithromycin also raises carbamazepine levels, but to a lesser extent. Studies suggest that azithromycin, flurithromycin, josamycin, midecamycin, and roxithromycin have no interaction, or no clinically significant interaction, with carbamazepine, but note that a case of carbamazepine toxicity has been reported in a patient given roxithromycin. 

Roxithromycin 150 mg twice daily for 8 days did not affect the pharmacokinetics ofa single 200-mg dose of carbamazepine in healthy subjects. " However, there is an isolated report of carbamazepine toxicity (levels increased to 21.7 mg/L) in a patient taking carbamazepine and atorvastatin the day after she started to take roxithromycin 150 mg twice daily. Roxithromycin and atorvastatin were stopped and carbamazepine levels fell to 12.5 mg/L within a day. The increased carbamazepine levels were attributed to the concurrent use of roxithromycin. ... 

It seems probable that clarithromycin, erythromycin and troleandomycin, and to a lesser extent some of the other macrolides, slow the rate of metabolism of the carbamazepine by the cytochrome P450 isoenzyme CYP3A4 so that the anticonvulsant accumulates within the body." " Telithromycin is predicted to interact similarly." It was suggested that the carbamazepine toxicity seen with roxithromycin may have been mediated by P-glycoprotein inhibition, which occurred as a result of an interaction between roxithromycin and atorvastatin. 

Corbin C, Mbsquet B, Lacotte J, Debn e D, Denise P, Viader F, Coquerel A. Surdosage en carbamazepine apres association a I atorv astatine et a la roxithromycine. Therapie (2004) 59, 267-9. 

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