This condition — the plain-language one-pager.

What is Thyroid Disease?Diagnosis

Your thyroid is a small butterfly-shaped gland in your neck that makes thyroid hormone — the metabolism dial for almost every cell. Hypothyroidism (underactive — most commonly Hashimoto's autoimmune thyroiditis) and hyperthyroidism (overactive — most commonly Graves' disease) are both common, and both are usually highly treatable. About 1 in 8 women develop a thyroid disorder in their lifetime; the rate is lower in men but still significant. The diagnostic workhorses are simple labs (TSH, free T4, often antibodies) — and the treatment is well-established.

• Hypothyroidism — Fatigue, weight gain, cold intolerance, dry skin, constipation, depression, hair loss, slow heart rate, brain fog. Diagnosis: elevated TSH + low free T4. Treatment: levothyroxine (Synthroid, Levoxyl, Tirosint) — start low, titrate by TSH every 6-8 weeks, target TSH 0.5-2.5 mIU/L for most.
• Hyperthyroidism — Weight loss, heat intolerance, palpitations, anxiety, tremor, diarrhea, insomnia, eye changes (Graves' ophthalmopathy). Diagnosis: low TSH + high free T4 + high free T3; antibodies (TSI/TRAb for Graves'); thyroid uptake scan. Treatment: methimazole (or PTU in pregnancy first trimester), radioactive iodine (RAI), or thyroidectomy.
• Subclinical disease is common — TSH abnormal but free T4 normal. Treatment is individualized: usually treat if symptomatic, pregnant/planning, antibody-positive, or TSH significantly out of range.
• Thyroid nodules — Found in ~50% of adults by ultrasound, but only ~5% are cancerous. Risk-stratify by ultrasound features (ATA / TI-RADS); biopsy when criteria met. Most thyroid cancers (papillary, follicular) have excellent prognosis.

Levothyroxine: take it right and check the TSHKnow your plan

Levothyroxine works beautifully when taken consistently and absorbed properly. Most "treatment failures" are absorption or timing issues — fix those, and the dose works. Always recheck TSH 6-8 weeks after any change.

• Take on empty stomach, 30-60 min before food/coffee — or at bedtime 4 hours after eating. Calcium, iron, soy, fiber, antacids, PPIs all reduce absorption.
• Same brand consistency — different manufacturers have different bioavailability. Generic switches can cause TSH swings.
• Recheck TSH every 6-8 weeks after dose change, then annually when stable. Pregnancy: more frequent.
• Pregnancy — increase dose ~25-30% as soon as positive test; check TSH every 4-6 weeks; tighter targets.
• Symptoms despite normal TSH — check free T4 + T3; rule out other causes (anemia, sleep apnea, depression, B12); occasional benefit from T3 (Cytomel) addition or NDT.

Your daily Force FieldLive It

• Take levothyroxine on empty stomach, 30-60 min before food/coffee; or at bedtime 4 hours after eating.
• Same brand each refill; do not switch generics without retesting TSH.
• Annual TSH when stable; q6-8 weeks after dose changes, in pregnancy, with new meds (estrogen, biotin can affect testing).
• Tell every clinician about your thyroid disease — affects med interactions, anesthesia, pregnancy planning.
• Hyperthyroidism: take ATD on schedule; monitor for agranulocytosis (sore throat + fever = stop + CBC); know the RAI vs surgery decision.
• Eye protection if Graves' ophthalmopathy — sunglasses, lubricating drops, head-of-bed elevation; teprotumumab for active moderate-severe.
• Annual screening for related autoimmune diseases — celiac, T1D, B12 deficiency, vitiligo.
• Iodine awareness — supplements + amiodarone + IV contrast can shift thyroid status. Check before contrast scans.
• Bone density in postmenopausal women on long-term levothyroxine; aim for TSH 0.5-2.5 mIU/L unless cancer history.
• Cardiovascular monitoring — both hypo and hyper raise CV risk; lipids, BP, A1C as standard.

Red flags — call nowAction

• Call your clinic the same day for: new chest discomfort with exertion that goes away with rest (stable angina worth evaluating); a missed dose of antiplatelet or statin; medication side effects (muscle aches, bleeding, GI symptoms).
• Bring up at next visit: any change in exercise tolerance, lipid follow-up timing, BP log review, smoking-cessation support, depression screening, sleep concerns.