Mono Nu, a 44 year-old Filipino patient comes to the clinic today to have his “blood thinner” labs drawn since he started them two weeks ago. Upon assessing the labs the nurse practitioner notes that he is still out of range. When assessing the patients compliance both stated that he had been taking them just as prescribed. He has been doing well and eating a diet rich in fish and tofu. He doesn’t understand why his medications are not working.

Title: Evaluation of Persistent Out-of-Range “Blood Thinner” Labs in a Filipino Patient

This case involves a 44-year-old Filipino patient, Mono Nu, who comes to the clinic to have his “blood thinner” labs assessed. Despite following the prescribed medication regimen and maintaining a diet rich in fish and tofu, his laboratory values are still out of range. This paper aims to analyze possible reasons for Mono Nu’s persistent lab results and provide recommendations for further evaluation and management.

Blood thinners, also known as anticoagulants, are commonly prescribed to prevent blood clotting and reduce the risk of thromboembolic events. They are widely used to manage conditions such as deep vein thrombosis, atrial fibrillation, and mechanical heart valves (Keeling et al., 2018).

In this case, it is important to note that the term “blood thinner” is a layman’s term often used to refer to oral anticoagulants, such as warfarin or direct oral anticoagulants (DOACs) like apixaban or rivaroxaban. The specific medication and therapeutic target for Mono Nu are not mentioned.

Understanding Out-of-Range Lab Results:
Before analyzing potential reasons for Mono Nu’s persistent out-of-range lab results, it is crucial to understand the parameters used to assess the efficacy of blood thinners.

The most common laboratory test to monitor the effect of anticoagulation therapy is the International Normalized Ratio (INR). INR measures the time it takes for blood to clot in comparison to a standard reference range (usually between 2.0 and 3.0 for most indications) (Keeling et al., 2018).

Possible Explanations for Persistent Out-of-Range Lab Results:

1. Genetic Factors:
Along with diet and medication compliance, genetic variations can influence the response to anticoagulant therapy. Certain gene polymorphisms, such as those affecting the VKORC1 and CYP2C9 genes, can alter the metabolism and sensitivity to warfarin, a commonly used oral anticoagulant (Pirmohamed et al., 2013). However, this is unlikely to be directly relevant to Mono Nu’s case, as his medication and specific blood thinner were not specified.

2. Drug Interactions:
Potential interactions between the blood thinner and other medications, supplements, or foods might contribute to the persistent out-of-range lab results. Many drugs, such as non-steroidal anti-inflammatory drugs (NSAIDs) or certain antibiotics, can influence the efficacy of various anticoagulants (Schelleman et al., 2010). It is important to evaluate Mono Nu’s medication profile and assess for potential interactions that could affect the anticoagulant’s effectiveness.

3. Inadequate Dosing:
Assuming Mono Nu is taking warfarin, the most commonly prescribed oral anticoagulant, dosage adjustments may be necessary to achieve the desired therapeutic range. Factors such as patient variability in drug metabolism, concurrent illnesses, or changes in diet can influence the drug’s effectiveness (Keeling et al., 2018). Therefore, it is essential to evaluate the dosage regimen and consider a potential need for dose adjustment or alternative anticoagulants.

4. Diet and Nutrition:
Mono Nu states that he consumes a diet rich in fish and tofu, suggesting a high intake of foods with potential anticoagulant effects. Fish, especially fatty fish like salmon or mackerel, are a source of omega-3 fatty acids, which possess mild anticoagulant properties (Fremont, 2000). Additionally, tofu, derived from soybeans, contains isoflavones that may impact hemostasis (McVeigh et al., 2016). It is essential to assess Mono Nu’s dietary habits and educate him on the potential interactions between his diet and his prescribed blood thinner.


1. Review Medication Profile and Dosing:
Evaluate Mono Nu’s specific medication and dosage regimen to ensure appropriateness and consider dose adjustments if necessary. Assess for potential drug interactions that could impact anticoagulant efficacy.

2. Genetic Testing:
Consider genetic testing, such as the identification of VKORC1 and CYP2C9 polymorphisms, to better understand Mono Nu’s response to anticoagulant therapy and guide treatment decisions if warfarin is the prescribed medication.

3. Encourage Dietary Counseling:
Provide Mono Nu with evidence-based dietary counseling regarding the potential interactions between his diet and his prescribed medication. Emphasize the need for moderation and balance in his overall diet, including fish and tofu consumption.

The evaluation of persistent out-of-range lab results in Mono Nu requires a comprehensive assessment of various factors, including genetic variations, drug interactions, dosing, and dietary habits. By addressing these potential contributing factors, healthcare providers can effectively manage and optimize the anticoagulation therapy to reduce the risk of thromboembolic events and improve patient outcomes.