Drug interactions between Coumadin and Keflex
Interactions between your drugs
warfarin ↔ cephalexin
Applies to:Coumadin (warfarin) and Keflex (cephalexin)
Consumer information for this interaction is not currently available.
MONITOR: Cephalosporins may potentiate the anticoagulant effects of vitamin K antagonists. Possible mechanisms include inhibited growth of vitamin K-producing intestinal bacteria, inhibited production of vitamin K-dependent clotting factors via a methylthiotetrazole (MTT) side chain (e.g., cefamandole, cefmetazole, cefoperazone, cefotetan), and/or inhibited platelet activity. Decreased prothrombin activity has been reported during treatment with various cephalosporins. Risk factors include renal or hepatic impairment, poor nutritional state, protracted antimicrobial therapy, and chronic anticoagulation therapy.
MANAGEMENT: Prothrombin time and INR should be monitored and the patient closely observed for signs of bleeding. The anticoagulant dose may be adjusted as indicated. Patients should be advised to notify their physicians if they experience any signs or symptoms that may indicate excessive anticoagulation, such as unusual or prolonged bleeding, bruising, coffee ground emesis, change in stool or urine color, headache, dizziness, or weakness.
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Drug and food interactions
Applies to: Coumadin (warfarin)
Nutrition and diet can affect your treatment with warfarin. Therefore, it is important to keep your vitamin supplement and food intake steady throughout treatment. For example, increasing vitamin K levels in the body can promote clotting and reduce the effectiveness of warfarin. While there is no need to avoid products that contain vitamin K, you should maintain a consistent level of consumption of these products. Foods rich in vitamin K include beef liver, broccoli, Brussels sprouts, cabbage, collard greens, endive, kale, lettuce, mustard greens, parsley, soy beans, spinach, Swiss chard, turnip greens, watercress, and other green leafy vegetables. Moderate to high levels of vitamin K are also found in other foods such as asparagus, avocados, dill pickles, green peas, green tea, canola oil, margarine, mayonnaise, olive oil, and soybean oil. However, even foods that do not contain much vitamin K may occasionally affect the action of warfarin. There are reports of patients who experienced bleeding complications and increased INR or bleeding times after consuming large quantities of cranberry juice, mangos, or pomegranate juice. Again, you do not need to avoid these foods completely, but it may be preferable to limit their consumption, or at least maintain the same level of use while you are receiving warfarin. Talk to a healthcare provider if you are uncertain about what foods or medications you take that may interact with warfarin. It is important to tell your doctor about all medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor. When warfarin is given with enteral (tube) feedings, you may interrupt the feeding for one hour before and one hour after the warfarin dose to minimize potential for interaction. Feeding formulas containing soy protein should be avoided.
Therapeutic duplication warnings
No therapeutic duplications were found for your selected drugs.
Drug Interaction Classification
|Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.|
|Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.|
|Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.|
|No information available.|
Do not stop taking any medications without consulting your healthcare provider.
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