Hypothyroidism

Hypothyroidism is when the thyroid gland makes too little thyroid hormone. It is extremely common in India — especially in women — with surveys suggesting over 10% of adult women are affected. The good news: it's easy to diagnose with a single blood test (TSH), and treatment (daily levothyroxine) is inexpensive, safe, and for most people, simple to take.

Common symptoms

• Fatigue, sluggishness, feeling cold.
• Weight gain despite no diet change.
• Dry skin, brittle hair, hair fall.
• Constipation.
• Muscle aches, joint pain, weakness.
• Slow heart rate, puffy face, swollen feet.
• Heavy or irregular periods, infertility, miscarriage.
• Low mood, poor concentration, memory lapses.
• Goitre (neck swelling) — especially in iodine-deficient regions.

Common causes

• Hashimoto's (autoimmune) thyroiditis — the commonest cause in India and worldwide.
• Iodine deficiency — less common now with iodised salt, but compliance gaps exist in parts of India (tribal areas, rural households using non-iodised/rock salt).
• Post-treatment — after radioactive iodine or thyroid surgery for hyperthyroidism or cancer.
• Medicines — amiodarone, lithium, some cancer drugs.
• Post-partum thyroiditis — transient, but needs follow-up.
• Congenital hypothyroidism — picked up by newborn screening in most states.

Diagnosis

• TSH is the single best screening test. Elevated TSH with low free T4 = hypothyroidism.
• Subclinical hypothyroidism — slightly raised TSH with normal T4. Treatment depends on age, symptoms, pregnancy plans, antibody status.
• Anti-TPO antibodies confirm Hashimoto's.

Treatment

• Daily levothyroxine tablet — taken on an empty stomach with water, 30–60 minutes before breakfast, tea, or coffee. Timing matters more than dose fine-tuning.
• Check TSH 6–8 weeks after starting or changing dose; annually when stable.
• Iron, calcium, soy, and PPI antacids reduce absorption — separate them by 4 hours.
• Usually lifelong for autoimmune hypothyroidism — don't stop because you "feel fine".
• Pregnancy and pre-conception: tighter targets (TSH < 2.5 in first trimester); doses usually rise 30–50% by second trimester. Get checked early if trying to conceive.
• Avoid "thyroid-curing" oils, supplements, and alternative medicines — none replace thyroxine. Kelp and iodine supplements can worsen thyroid disease.

Red flags

• Sudden drowsiness, very slow pulse, low temperature, unconsciousness (myxoedema coma) — emergency.
• New thyroid swelling that is hard, fixed, or growing — see ENT (rule out cancer).
• Planning pregnancy — check TSH before conception.