Final answer:
The medical assistant should advise the patient to consult their healthcare provider regarding how their medications may affect occult blood testing results.
Step-by-step explanation:
When instructing a patient on collecting stool specimens at home for occult blood testing, it is essential to address the impact of medications on the test results. Certain medications can influence the outcomes of fecal occult blood tests, possibly causing false positives or negatives. Therefore, the medical assistant should tell the patient to consult with their healthcare provider regarding the impact of their current medications on the test results. This step ensures that the testing process is reliable and that any necessary medication adjustments are professionally managed.