Drug General Information (ID: DDIAMS4PVX)
Drug Name			Lidocaine		Drug Info		Bretylium		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Anesthetics				Antiarrhythmic Agents
Structure

Mechanism of Lidocaine-Bretylium Interaction (Severity Level: Moderate)
Increased risk of atrioventricular block Click to Show/Hide Mechanism Graph
Drug Name		Lidocaine				Bretylium
Mechanism 1		Delay atrioventricular conduction				Delay atrioventricular conduction
Key Mechanism Factor 1
		Factor Name		Atrioventricular block
		Factor Description		Atrioventricular block is a type of cardiac conduction block that occurs when the electrical signal from the atria to the ventricles is impaired. In an Atrioventricular block, this electrical signal is either delayed or completely blocked. When the signal is completely blocked, the ventricles produce their own electrical signal to control the heart rate. The heart rate produced by the ventricles is much slower than that produced by the sinus node.
Mechanism Description		Increased risk of atrioventricular block by the combination of Lidocaine and Bretylium
Increased risk of bradycardia Click to Show/Hide Mechanism Graph
Drug Name		Lidocaine				Bretylium
Mechanism 2		Bradycardia				Bradycardia
Key Mechanism Factor 2
		Factor Name		Bradycardia
		Factor Description		Bradycardia is a slow heart rate in which the heart beats less than 60 times per minute. If the heart rate is very slow and the heart is not pumping enough oxygen-rich blood to the body, and you may feel dizzy, very tired or weak, and short of breath.
Mechanism Description		Increased risk of bradycardia by the combination of Lidocaine and Bretylium

Recommended Action
Management		Patients treated with class III antiarrhythmic agents (e.g., amiodarone, dofetilide, ibutilide, sotalol) should be under close surveillance during administration of amide-type local anesthetics. ECG monitoring should be considered.

References
1	Keidar S, Grenadier E, Palant A "Sinoatrial arrest due to lidocaine injection in sick sinus syndrome during amiodarone administration." Am Heart J 104 (1982): 1384-5. [PMID: 7148661]
2	Product Information. Naropin (ropivacaine). Astra USA, Westborough, MA.