Interaction between Folic acid and Carbamazepine
Moderate Antagonism

ID DDInter771 and DDInter293
Interaction Anticonvulsants including, but not limited to, carbamazepine, lamotrigine, phenobarbital, phenytoin, primidone, and valproic acid have been shown to impair folate absorption and increase the metabolism of circulating folate. Coadministration with folate therapy may reduce the anticonvulsant effects of phenytoin, phenobarbital, primidone, and succinimides. The exact mechanism of interaction is unknown. Available data pertain primarily to phenytoin.
birth defect abortion spontaneous premature separation of placenta acanthosis nigricans agranulocytoses amblyopia amenorrhea anaemia angina Anorexia More
Management Caution is advised when folate therapy is coadministered with anticonvulsants. Close monitoring for clinical and laboratory evidence of diminished therapeutic response to both treatments is recommended. Patients should be advised to notify their physician if they experience loss of seizure control.
References
Alternative for Folic acid B03A
Iron
Iron sucrose
Ferrous fumarate
Ferrous gluconate

V04C
Histamine
Galactose
Methacholine
Metyrapone
Magnesium sulfate
Edrophonium
Vitamin A
More
Alternative for Carbamazepine N03A
Trimethadione
Lacosamide
Cannabidiol
Brivaracetam
Tiagabine
Paramethadione
Phenacemide
Stiripentol
Vigabatrin
Perampanel
Ezogabine

Potential Metabolism Interactions

Substrate-Substrate Interaction：If more than one drug is metabolized by the same CYP, it is possible that its metabolism is inhibited because of the competition between the drugs. That means, it can be useful to lower the dosage of the drugs in the drug-cocktail because they remain longer in the organism than in monotherapy.
Inhibitor-Inhibitor Interaction：Combining two or more inhibitors of one CYP, should be compensated by lowering the dosage of these drugs because the metabolism is reduced and the drugs remain longer in the organism than in monotherapy. Not adapting the dosage bears the risk of even more side effects.
Inhibitor-Substrate Interaction：Combining drugs that have inhibitory effect and are substrates of one particular CYP, should be compensated by lowering the dosage. They rest longer in the organism than in monotherapy. Not adapting the dosage bears the risk of even more side effects.