Carbamazepine/Selected Azole Antifungals
This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.
Medical warning:
Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
Fluconazole and ketoconazole may slow down how quickly your liver processes carbamazepine.Carbamazepine may speed up how quickly your liver processes itraconazole.
What might happen:
If you take fluconazole or ketoconazole with your carbamazepine, the amount of carbamazepine in your blood may increase and it may cause toxic side effects such as drowsiness, dizziness, blurred vision, or loss of coordination.If you take itraconazole with your carbamazepine, the amount of itraconazole in your blood may decrease and it may not work as well.
What you should do about this interaction:
Let your healthcare professionals (e.g. doctor or pharmacist) know that you are taking these medicines together.If you are taking fluconazole or ketoconazole, your doctor may want to check the amount of carbamazepine in your blood during and after your treatment with fluconazole or ketoconazole. Your doctor may need to change the dose of your carbamazepine during and after your treatment with fluconazole or ketoconazole. Let your doctor know right away if you have any symptoms of carbamazepine toxicity.If you are taking itraconazole, let your doctor know if your condition does not improve or worsens. Your doctor may need to change your antifungal medicine.If you are unsure which antifungal agent you are taking, ask your healthcare professional.Your healthcare professionals may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.
References:
1.Ulivelli M, Rubegni P, Nuti D, Bartalini S, Giannini F, Rossi S. Clinical evidence of fluconazole-induced carbamazepine toxicity. J Neurol 2004 May; 251(5):622-3.
2.Nair DR, Morris HH. Potential fluconazole-induced carbamazepine toxicity. Ann Pharmacother 1999 Jul-Aug;33(7-8):790-2.
3.Finch CK, Green CA, Self TH. Fluconazole-carbamazepine interaction. South Med J 2002 Sep;95(9):1099-100.
4.Spina E, Arena D, Scordo MG, Fazio A, Pisani F, Perucca E. Elevation of plasma carbamazepine concentrations by ketoconazole in patients with epilepsy. Ther Drug Monit 1997 Oct;19(5):535-8.
5.Pirmohamed M, Kitteringham NR, Guenthner TM, Breckenridge AM, Park BK. An investigation of the formation of cytotoxic, protein-reactive and stable metabolites from carbamazepine in vitro. Biochem Pharmacol 1992 Apr 15; 43(8):1675-82.
6.Pearce RE, Vakkalagadda GR, Leeder JS. Pathways of carbamazepine bioactivation in vitro I. Characterization of human cytochromes P450 responsible for the formation of 2- and 3-hydroxylated metabolites. Drug Metab Dispos 2002 Nov;30(11):1170-9.
7.Bonay M, Jonville-Bera AP, Diot P, Lemarie E, Lavandier M, Autret E. Possible interaction between phenobarbital, carbamazepine and itraconazole. Drug Saf 1993 Oct;9(4):309-11.
8.Tucker RM, Denning DW, Hanson LH, Rinaldi MG, Graybill JR, Sharkey PK, Pappagianis D, Stevens DA. Interaction of azoles with rifampin, phenytoin, and carbamazepine: in vitro and clinical observations. Clin Infect Dis 1992 Jan;14(1):165-74.
