I am a 37 y/o female who has been feeling serious fatigue. my tsh is 1.5, free t3 (liothyronine) is 2.5, and my free t4 is .5. should i be treated for hypothyroidism?

Hypothyroidism: The most sensitive study for hypothyroidism is the TSH as a rule. Not knowing the standards for the laboratory makes decision making difficult but your labs appear normal based on standards that I am familiar. Other causes for your symptoms must be persued.

Possibly: Cannot just go by tsh. Looks like you may have a slight thyroid problem. Your free T3 seems low. Check free T3 and reverse t3. Ft3 should be in upper range and rt3 in lower range. If your ratio is off, you may need Armour Thyroid or t3, and synthroid (thyroxine) would be the wrong med for you. Tsh only tells us how the pituitary is feeling, not the rest of the body.

Undiagnosed hypoT?: Hypothyroidism can be primary - caused by a weak thyroid gland or secondary to other hormonal problems, like a pituitary problem. Or your thyroid can become dysfunctional secondary to high insulin, estrogen or cortisol. If you have functional hypothyroidism, this problem can go undetected by routine screening tests. More extensive testing can often reveal abonormalities. This is very common.