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TheraGuide® 5-FU: Personalized Medicine for Customized Chemotherapy

TheraGuide® 5-FU is a blood test that enables physicians to customize chemotherapy and take action to minimize side effects.

There is tremendous benefit to identifying the risk of severe side effects before starting a 5-FU treatment. Knowing whether or not the patient is at high risk for side effects will help to make the best possible treatment decisions.

With a positive result, physicians may adjust dosing or choose a different treatment because the patient is unable to tolerate 5-FU.

With a negative result, the physician is assured that they have ruled out many toxicity risks related to DPYD and TYMS genetic variations.

One in four patients carry variations in either of two genes, DPYD or TYMS that will increase their risk of dose limiting adverse events to 5-FU-related therapy. The test requires only a small sample of the patient’s blood, which is sent to Myriad for analysis.

Predicting and Managing Chemotoxicity

Some patients on 5-FU can experience severe dose limiting toxicities. These complications include neutropenia, diarrhea, hand-foot syndrome, stomatitis, mucositis and myelosuppression.  These toxicities can have significant effects on treatment time and cost including:

  • Dose reductions
  • Treatment delays
  • Changes in or discontinuation of therapy
  • Extra interventions to address potentially harmful side effects
  • Fluid- and nutritional-replacement therapies
  • Hematopoietic-stimulating therapies
  • Antibiotics
  • Clinic and hospital visits
  • Patient discomfort and diminished quality of life
  • Hospitalization

Benefits of TheraGuide 5-FU Testing

TheraGuide 5-FU is the only test that provides a comprehensive analysis of DPYD and TYMS gene variations to predict and help prevent 5-FU-related adverse events. This simple blood test identifies potential toxicity before it occurs.

Rapid results provide timely identification of high-risk patients before starting chemotherapy, allowing a personalized approach to treatment

Early Detection of Toxicity Risk by TheraGuide 5-FU Helps You To:

  • Prevent toxicity in high-risk patients by individualizing treatment for optimal therapeutic response
  • Better determine alternate therapies for at-risk patients
  • Implement dose reduction and monitoring strategies where appropriate
  • Improve patient quality of life


For more physician information or to order a TheraGuide 5-FU test kit, please visit MyriadPro