INR Above or Below the Therapeutic Range
Increased INR, Coumadin over-dosage; low INR, inadequate Coumadin dosage
Clinical conditions that increase Coumadin effect and elevate INR include:
Low vitamin K intake
Poor nutritional state
Congestive heart failure
Connective tissue diseases
Conditions known to decrease Coumadin effect and decrease INR include:
High vitamin K intake
Many drugs are known to increase warfarin effect and elevate INR:
Effects may be dose-dependent & may not occur in all pts receiving Coumadin & the drug mentioned.
Drugs in this category include carbenicillin, allopurinol, erythromycin, indomethacin, ibuprofen, fluconazole, fenoprofen, isoniazid, ketoconazole, naproxen, metronidazole, phenylbutazone, moxalactam, cephalosporins, trimethoprim-sulfa (Bactrim), amiodarone, quinidine, cimetidine, clofibrate, lovastatin, omeprazole, phenytoin, tamoxifen, thyroxine, quinolones, rofecoxib, celecoxib.Drugs that can decrease warfarin effect & lower INR in some pts include antacids, antihistamines, barbiturates, rifampin, sucralfate, trazodone, carbamazepine, cholestyramine, griseofulvin, haloperidol, oral contraceptives, penicillin, dicloxacillin, and nafcillin.
Suggested Additional Lab Testing
Most important: INR value on a daily basis until patient shows a consistent value within therapeutic range at least 2 or 3 times.
Monitoring is then less frequent but at least 1 times per month.
Lab tests may be helpful in uncovering other conditions, such as liver disease, which lowers the level of coagulation factors and makes therapeutic anticoagulation difficult. Pharmacogenomics testing is a consideration, either before initiation of warfarin, shortly after initiation, or for patients with apparent hypersensitivity to warfarin.
Copyright © 2017, 2013 Decision Support in Medicine, LLC. All rights reserved.
No sponsor or advertiser has participated in, approved or paid for the content provided by Decision Support in Medicine LLC. The Licensed Content is the property of and copyrighted by DSM.
Sign Up for Free e-newsletters
- Hodgkin Lymphoma Survivorship Marked by Periods of Actionable Distress
- Medication, Vaccination Uptake Improved by Involving Pharmacists in Elder Cancer Care
- Molecular Features May Predict Response in Primary Pancreatic Cancer
- Stem Cell Transplantation Superior to Chemotherapy for Relapsed/Refractory DLBCL, Follicular Lymphoma
- Commission Seeks Standardized Adverse Event Assessments in Hematologic Malignancies
- Navigating Prostate Cancer: A Patient's Experience From Diagnosis to Survivor
- Cell Phones and Cancer Risk (Fact Sheet)
- How Likely Are Oncologists to Refer for Palliative Care? Depends on Their Age
- Use of Corticosteroids With PD-1 or PD-L1 Inhibitors Associated With Poorer Outcomes in NSCLC
- Chemoimmunotherapy Increases Survival in Triple-Negative Breast Cancer
- Integrative Medicine in Childhood Cancer: Practices That Can Help Pediatric Patients
- Clinical Characteristics That Increase Risk of Chemotherapy-Induced Febrile Neutropenia Identified
- Dose-Escalation Mitigates Risk of Grade 3/4 Adverse Events With Ruxolitinib for Myelofibrosis
- Counseling Patients on Oral Chemotherapy
- Patients and Caregivers Worry About Cost of Cancer Care
Regimen and Drug Listings
GET FULL LISTINGS OF TREATMENT Regimens and Drug INFORMATION
|Head and Neck Cancer||Regimens||Drugs|