Questions: Which lab result for a female patient may indicate that drug therapy effectiveness may be altered? - Calcium = 12 mg / dL - Creatinine kinase = 88 units/L - White blood cells = 9000 / mm^3 - Hemoglobin = 9 g / dL

The lab result that may indicate that drug therapy effectiveness may be altered is:

○ Hemoglobin $=9 \mathrm{~g} / \mathrm{dL}$

Explanation for each option:

1. Calcium $=12 \mathrm{mg} / \mathrm{dL}$: This value is slightly above the normal range for calcium, which is typically 8.5 to 10.5 mg/dL. While elevated calcium levels can indicate certain conditions, they are not directly indicative of altered drug therapy effectiveness unless the drug specifically affects calcium metabolism.

2. Creatinine kinase $=88$ units/L: This value is within the normal range for creatinine kinase, which is generally 20 to 200 units/L. Normal creatinine kinase levels suggest that there is no muscle damage or other conditions that might affect drug metabolism.

3. White blood cells $=9000 / \mathrm{mm}^{3}$: This is a normal white blood cell count, as the typical range is 4,000 to 11,000/mm³. A normal white blood cell count does not suggest any alteration in drug therapy effectiveness.

4. Hemoglobin $=9 \mathrm{~g} / \mathrm{dL}$: This value is below the normal range for hemoglobin in females, which is typically 12 to 16 g/dL. Low hemoglobin levels indicate anemia, which can affect the distribution and effectiveness of certain drugs, particularly those that rely on adequate oxygen transport or are affected by blood volume.

In summary, the low hemoglobin level is the most likely indicator that drug therapy effectiveness may be altered, as it suggests anemia, which can impact how drugs are metabolized and distributed in the body.