Combining-Carbamazepine-Valproic acid
From Psychiatrienet
| ||||||||||||||||||||||||||||||||||||||
| ||||||||||||||||||||||||||||||||||||||
Adding valproic acid to carbamazepine.
General information- Carbamazepine is principally metabolized by CYP3A4, and is a potent inducer of CYP1A2, CYP2C9, CYP3A4 and UDP-glucuronosyltransferases.
- Valproic acid is principally metabolized by CYP2C9, CYP2C19, CYP2A6 and UDP-glucuronosyltransferases. Valproic acid is an inhibitor of the enzymes CYP2C9, epoxide-hydroxylase and UDP-glucuronosyltransferases.
- A synergistic effect is suggested.[5]
Start valproic acid- Define carbamazepine serum concentration (+ epoxide) before starting valproate. Check carbamazepine serum concentration (+ epoxide) again after 2 weeks and adapt dose if necessary. [6]
Cave- Valproate can inhibit carbamazepine metabolic pathways, resulting in raised carbamazepine-epoxide concentrations. [7]. Valproate can also displace protein-bound carbamazepine and therefore increase the levels of free carbamazepine. This may result in neurotoxicity even when valproate levels are low.[5]
- Carbamazepine induces metabolism of both itself and valproate via Cytochrome P450 3A3/4 system, which may decrease the serum concentrations of both drugs and increase the risk of relapse.[5]
- ↑ WHO Collaborating Centre for Drug Statistics Methodology ATC=N03AF01
- ↑ 2.0 2.1 Farmacotherapeutisch Kompas; Toxicologie (dutch)
- ↑ 3.0 3.1 Farmacotherapeutisch Kompas - carbamazepine (dutch)
Cite error: Invalid
<ref>tag; name "ftk" defined multiple times with different content - ↑ 4.0 4.1 KNMP; Informatorium Medicamentorum 2023; Monografie "carbamazepine" (Dutch)
Cite error: Invalid
<ref>tag; name "informatorium" defined multiple times with different content - ↑ 5.0 5.1 5.2 Freeman et al. Mood stabilizer Combinations: A Review of Safety and Efficacy. Am J Psychiatry 1998;155:12-21
- ↑ Schalekamp T. et al, Interacties met Psychofarmaca, Stichting Health Base, Houten, 2002.
- ↑ Bernus et al. The mechanism of the carbamazepine-valproate interaction in humans. Br J Clin Pharmacol 1997;44:21
The editors of psychiatrienet.nl take the greatest care to provide up-to-date and accurate information on this site. Nevertheless, mistakes and omissions cannot be entirely excluded. No rights devolve from the information provided. The editors and other providers of information to this site accept no responsibility for the content of this site or for the information provided therein; neither do they accept responsibility for possible damages which may derive from the use of the information on this site or from the linked sites. The editorial board accepts no responsibility for the content of the (linked) sites, for access to them, or for the products and services on these sites, nor for the occurrence of errors, viruses, and/or disruptions in service.
