What does a low FT4 result mean?

A low FT4 (free thyroxine) result typically suggests hypothyroidism, but it is not diagnostic on its own. TSH, FT3, and possibly thyroid antibodies must be considered. Low FT4 can also occur in non-thyroidal illness, malnutrition, or due to certain medications. Interpretation depends on the lab's reference range and the individual's clinical context. Medical follow-up is essential. The provided context lacks specific FT4 studies; this answer is based on general clinical practice. Evidence: practice (guidelines). Caveat: home tests are screening tools, not diagnostic.