HealthCareMagic is now Ask A Doctor - 24x7 | https://www.askadoctor24x7.com

Get your health question answered instantly from our pool of 18000+ doctors from over 80 specialties
159 Doctors Online

By proceeding, I accept the Terms and Conditions

Dr. Andrew Rynne
MD
Dr. Andrew Rynne

Family Physician

Exp 50 years

HCM Blog Instant Access to Doctors
HCM BlogQuestions Answered
HCM Blog Satisfaction

Does Amoxycillin Intake Increase INR Lvels?

it is common that antibiotic eg amoxycillin taken while on warfarin dosage increases INR level, but my INR level in this situation has decreased to 1.4 (range 2-3); I have completed my week long dosage of the antibiotic and felt OK with no adverse symptons all along. My GP directed me to continue the same warfarin dosage and have INR check in a week for further directions
Fri, 5 Sep 2014
Report Abuse
Internal Medicine Specialist 's  Response
Hi,

Thank you for your query. I can understand your concerns.






Amoxicillin oral increases effects of warfarin oral . INR levels may increase.Use with caution ;Although the mechanism for this interaction is not fully known, it is suspected that a decrease in vitamin K-producing gut flora with resulting vitamin K deficiency would be the most likely contributing factor.
Using warfarin together with amoxicillin may increase the risk of bleeding, especially if you are elderly or have kidney or liver impairment. You may need more frequent monitoring of your prothrombin time or INR by your doctor to safely use both medications.
However some study did not find Amoxiclav(amoxicillin/clavulanic acid) modifying anticoagulation in patients treated with stable warfarin therapy and without infection.
This may explain your INR not going up with concurrent amoxycillin therapy.
Regards

Dr. T.K. Biswas M.D.
Mumbai
I find this answer helpful

Note: Do you have more questions on diagnosis or treatment of blood disorders? Ask An Expert/ Specialist Now
Disclaimer: These answers are for your information only and not intended to replace your relationship with your treating physician.
This is a short, free answer. For a more detailed, immediate answer, try our premium service [Sample answer]
Share on
 

Related questions you may be interested in


Recent questions on Warfarin


Loading Online Doctors....
Does Amoxycillin Intake Increase INR Lvels?

Hi, Thank you for your query. I can understand your concerns. Amoxicillin oral increases effects of warfarin oral . INR levels may increase.Use with caution ;Although the mechanism for this interaction is not fully known, it is suspected that a decrease in vitamin K-producing gut flora with resulting vitamin K deficiency would be the most likely contributing factor. Using warfarin together with amoxicillin may increase the risk of bleeding, especially if you are elderly or have kidney or liver impairment. You may need more frequent monitoring of your prothrombin time or INR by your doctor to safely use both medications. However some study did not find Amoxiclav(amoxicillin/clavulanic acid) modifying anticoagulation in patients treated with stable warfarin therapy and without infection. This may explain your INR not going up with concurrent amoxycillin therapy. Regards Dr. T.K. Biswas M.D. Mumbai