Drug General Information (ID: DDIYCEX5H0)
Drug Name			Phenytoin		Drug Info		Bupivacaine		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Anticonvulsants				Anesthetics
Structure

Mechanism of Phenytoin-Bupivacaine Interaction (Severity Level: Minor)
Competitive binding of plasma proteins Click to Show/Hide Mechanism Graph
Drug Name		Phenytoin				Bupivacaine
Mechanism		Competition for plasma protein binding sites				Competition for plasma protein binding sites
Key Mechanism Factor 1
		Factor Name		Plasma protein binding
		Factor Description		Plasma protein binding refers to the degree of binding of a drug to proteins in the blood, and the lower the degree of binding, the more efficiently the drug can cross cell membranes or diffuse. Plasma protein binding alters the distribution and therapeutic characteristics of the drugs.
Mechanism Description		Increased plasma concentration of Bupivacaine and Phenytoin due to competitive binding of plasma proteins

References
1	Cerner Multum, Inc. "UK Summary of Product Characteristics.".
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3	Product Information. Marcaine HCl (bupivacaine). Hospira Inc, Lake Forest, IL.
4	Product Information. Zynrelef (bupivacaine-meloxicam). Heron Therapeutics, Redwood City, CA.
5	Skold A, Cosco DL, Klein R "Methemoglobinemia: pathogenesis, diagnosis, and management." South Med J 104 (2011): 757-61. [PMID: 22024786]