Drug General Information (ID: DDIEJD9XBZ)
Drug Name			Diltiazem		Drug Info		Propranolol		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Antihypertensive Agents				Antianxiety Agents
Structure

Mechanism of Diltiazem-Propranolol Interaction (Severity Level: Major)
Increased risk of cardiac depression Click to Show/Hide Mechanism Graph
Drug Name		Diltiazem				Propranolol
Mechanism		Cardiac depressant effects				Cardiac depressant effects
Key Mechanism Factor 1
		Factor Name		Cardiac depression
		Factor Description		Cardiac depression may manifest as negative heart rate, negative conduction, and negative contractility. Symptoms include: excessive or more than normal sleep, irritability, loss of interest in activities, and fatigue.
Mechanism Description		Increased risk of cardiac depression by the combination of Diltiazem and Propranolol

Recommended Action
Management		Close clinical monitoring of patient hemodynamic response and tolerance is recommended if these agents are used together, and the dosage of one or both agents adjusted as necessary. Patients should be advised to promptly report any symptoms including fatigue, headache, fainting, swelling of the extremities, weight gain, shortness of breath, chest pain, increased or decreased heartbeat, or irregular heartbeat.

References
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