Drug General Information (ID: DDI8GD1PEW)
  Drug Name Dicoumarol Drug Info Aztreonam Drug Info
  Drug Type Small molecule Small molecule
  Therapeutic Class Anticoagulants Antibiotics
  Structure

 Mechanism of Dicoumarol-Aztreonam Interaction (Severity Level: Moderate)
     Increased risk of bleeding Click to Show/Hide Mechanism Graph
Could Not Find 2D Structure
      Drug Name Dicoumarol Aztreonam
      Mechanism Vitamin K antagonist Inhibition of vitamin K-producing intestinal bacteria
      Key Mechanism Factor 1
Factor Name Bleeding
Factor Description Patients may be at risk for bleeding when the outcome of a disease or disease treatment confounds the standard mechanisms for maintaining hemostasis. Signs or symptoms of abnormal bleeding include: bleeding that takes a long time to stop (including nosebleeds, bleeding gums, bleeding from cuts and abrasions, and menstrual bleeding); severe unexplained bruising, or bruising that becomes larger; blood in the urine or stool, etc.
      Mechanism Description
  • Increased risk of bleeding by the combination of Dicoumarol and Aztreonam 

Recommended Action
      Management Given the potential for clinically significant interaction and even fatality in the occasional, susceptible patient, monitoring is recommended during concomitant therapy. The INR should be checked frequently and coumarin dosage adjusted accordingly, particularly following initiation or discontinuation of the antibacterial therapy in patients who are stabilized on their anticoagulant regimen. Patients should be advised to promptly report any signs of bleeding to their physician, including pain, swelling, headache, dizziness, weakness, prolonged bleeding from cuts, increased menstrual flow, vaginal bleeding, nosebleeds, bleeding of gums from brushing, unusual bleeding or bruising, red or brown urine, or red or black stools.

References
1 Agencia Espaola de Medicamentos y Productos Sanitarios Healthcare "Centro de informacion online de medicamentos de la AEMPS - CIMA.".
2 Cerner Multum, Inc. "UK Summary of Product Characteristics.".
3 Guo LQ, Yamazoe Y "Inhibition of cytochrome P450 by furanocoumarins in grapefruit juice and herbal medicines." Acta Pharmacol Sin 25 (2004): 129-36. [PMID: 14769198]