OBJECT DRUGS

Anticoagulants, Oral:

• Acenocoumarol
• Warfarin (Coumadin, etc.)

PRECIPITANT DRUGS

• Cimetidine (Tagamet, etc.)

Comment:

Cimetidine increases the hypoprothrombinemic response to warfarin. Although the effect is usually modest, it is also highly variable from patient to patient; hence, an occasional patient may develop a substantial increase in warfarin response.

Class 3: Assess Risk & Take Action if Necessary

• Consider Alternative: Other acid suppressors are unlikely to interact. Consider using famotidine (Pepcid), nizatidine (Axid), ranitidine (Zantac), dexlansoprazole (Kapidex), lansoprazole (Prevacid), rabeprazole (Aciphex), omeprazole (Prilosec), esomeprazole (Nexium), or pantoprazole (Protonix).
• Monitor: If the combination is used, monitor for altered warfarin response when cimetidine is initiated, discontinued, or changed in dosage.