Drug General Information (ID: DDIO14DVYZ)
Drug Name			Timolol (ophthalmic)		Drug Info		Tocainide		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Antiarrhythmic Agents				Antiarrhythmic Agents
Structure

Mechanism of Timolol (ophthalmic)-Tocainide Interaction (Severity Level: Moderate)
Increased risk of bradycardia Click to Show/Hide Mechanism Graph
Drug Name		Timolol (ophthalmic)				Tocainide
Mechanism		Bradycardia				Bradycardia
Key Mechanism Factor 1
		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 Timolol (ophthalmic) and Tocainide

Recommended Action
Management		The concomitant use of tocainide and beta blockers should probably be avoided in patients with atrioventricular conduction abnormalities or sick sinus syndrome. This combination should be used cautiously in other patients, with careful dose titration and close clinical and electrocardiographic monitoring for efficacy and safety.

References
1	Rubino M, Jackson E "Severe paranoia with concomitant tocainide and propranolol therapy." Clin Pharm 1 (1982): 177-9
2	Ikram H "Hemodynamic and electrophysiologic interactions between antiarrhythmic drugs and beta blockers, with special reference to tocainide." Am Heart J 100 (1980): 1076-80
3	Roden DM, Woosley RL "Tocainide." N Engl J Med 315 (1986): 41-5