Thyroid Testing and Consultation in Patong, Phuket: TSH, Free T4, and Hypo/Hyperthyroid Management

Clinically reviewed by the Doctor Patong Takecare Clinic medical team.

Talk to us now: WhatsApp +66 95 073 5550 | Call +66 81 718 9080 | Find us on Maps

The thyroid is a small butterfly-shaped gland in the front of the neck that controls metabolism, body temperature, heart rate, mood and menstrual cycles. When it underproduces or overproduces hormone, symptoms creep in slowly and are easily mistaken for stress, ageing, perimenopause or burnout. Many Patong patients first notice unexplained fatigue, weight change, hair thinning or palpitations on holiday, and walk in for a simple blood test that changes the diagnosis. Our clinic offers same-day TSH and full thyroid panels, results within hours, and prescriptions filled the same visit.

Thyroid tests we offer

TSH is the primary screening test because the pituitary is exquisitely sensitive to small changes in thyroid output. If TSH is normal in an otherwise well patient, no further test is usually needed. When TSH is abnormal, we add free T4 and free T3 to confirm the direction and severity. Antibody panels then tell us why. Anti-TPO (thyroid peroxidase) and anti-Tg (thyroglobulin) antibodies confirm Hashimoto’s autoimmune thyroiditis, the leading cause of hypothyroidism. TRAb (TSH receptor antibody) or TSI confirms Graves’ disease, the leading cause of hyperthyroidism. Thyroid ultrasound assesses nodules and goitre, calcitonin screens for medullary thyroid cancer in selected patients, and thyroglobulin is used to monitor recurrence after thyroidectomy.

Hypothyroidism (underactive thyroid)

Hypothyroidism shows a high TSH with a low free T4. The commonest cause worldwide is Hashimoto’s thyroiditis, confirmed by a positive anti-TPO antibody. Typical symptoms include fatigue, weight gain despite no change in diet, cold intolerance, constipation, dry skin, hair loss, low mood or depression, heavier or longer periods, and a slow heart rate. Many patients feel “not quite right” for months before testing.

Treatment is levothyroxine at a starting dose of approximately 1.6 micrograms per kilogram per day, which works out near 100 micrograms for an average adult. Older patients and those with heart disease begin lower and titrate up. We aim for a TSH between 0.5 and 2.5 mIU/L and recheck six to eight weeks after every dose change. Once stable, an annual TSH is enough. Treatment is usually lifelong. The tablet must be taken fasting, 30 to 60 minutes before food, calcium, iron supplements or coffee, all of which block absorption.

Subclinical hypothyroidism means a high TSH with a normal free T4. We treat when TSH is above 10 mIU/L, when symptoms are clearly present, when anti-TPO is positive, in pregnancy, in women planning pregnancy, and in cases of infertility. In pregnancy the target TSH is tighter: below 2.5 in the first trimester and below 3.0 in the second and third. Existing levothyroxine doses typically need to rise by 25 to 50 percent once a pregnancy test turns positive, with bloods rechecked every four to six weeks.

Hyperthyroidism (overactive thyroid)

Hyperthyroidism shows a low TSH with raised free T4 or T3. Graves’ disease is the most common cause, confirmed by a positive TRAb antibody, and typically produces a diffuse smooth goitre, eye signs such as bulging or staring, and rarely pretibial myxoedema (thickened skin over the shins). A single toxic nodule or a toxic multinodular goitre appears as one or several hot areas on a thyroid scan. Thyroiditis after a viral infection, after pregnancy, or from drugs such as amiodarone causes a transient phase of hyperthyroidism that often swings into temporary hypothyroidism before recovering.

Symptoms include weight loss despite a good appetite, palpitations, tremor, heat intolerance, anxiety, frequent loose stools, lighter or absent periods, insomnia and eye changes. Treatment depends on the cause and the patient. Methimazole at 10 to 30 milligrams daily is the first-line drug for most adults. Propylthiouracil at 100 to 300 milligrams daily is preferred in the first trimester of pregnancy due to its better safety profile in early gestation. Beta-blockers such as propranolol control the tremor and palpitations while we wait for the antithyroid drugs to take effect. Definitive treatment with radioactive iodine or thyroid surgery is arranged through endocrinology referral when relapse occurs or when long-term medical therapy is not suitable.

Thyroid nodules and goitre

Thyroid nodules are common and the vast majority are benign. We arrange an ultrasound with TIRADS risk stratification, a system that scores nodules from 1 (normal) to 5 (highly suspicious) based on shape, margins, echogenicity and microcalcifications. Nodules with intermediate or high risk scores are referred for fine-needle aspiration (FNA) cytology with endocrinology or thyroid surgery. A large goitre that causes a visible neck swelling, difficulty swallowing or pressure on the airway needs prompt referral regardless of biochemistry.

Warning signs that need urgent care

Prevention, monitoring and the Phuket expat context

Most thyroid disease cannot be prevented because the causes are autoimmune or genetic, but it can be caught early. Many of our long-term Patong patients are expats on lifelong levothyroxine who need annual TSH testing, prescription refills, and dose adjustments after weight change, pregnancy or starting other medications. We keep a record of your previous results, brand and dose so refills are quick. Women planning pregnancy benefit from a pre-conception TSH check, especially with a personal or family history of thyroid disease. If you take iron, calcium or proton pump inhibitors, separate them from your levothyroxine by at least four hours to protect absorption.

Summary

Thyroid disease is common, often silent, and easily missed in busy travellers and expats. A single TSH test, followed by a focused panel when needed, settles most diagnoses. Hypothyroidism responds well to levothyroxine taken correctly, hyperthyroidism is controlled with methimazole or propylthiouracil and referred where appropriate, and most nodules are benign but deserve an ultrasound. We coordinate care with endocrinology and surgical specialists when those steps are needed. Related metabolic and mood symptoms such as fatigue, weight change, palpitations or anxiety are also worth assessing for diabetes and for anxiety, both of which overlap clinically.

“A TSH test takes minutes, the result comes back the same day, and the answer often explains months of unexplained symptoms. We treat, monitor and refill prescriptions for expats and travellers so thyroid care never gets interrupted by a move overseas.” Doctor Patong Takecare Clinic medical team.

Frequently asked questions

Do I need treatment for subclinical hypothyroidism?

Not always. We treat when TSH is above 10 mIU/L, when clear symptoms are present, when anti-TPO is positive, in pregnancy or pre-pregnancy, and in cases of infertility. Otherwise we monitor with a repeat TSH at three to six months. Many borderline cases never progress.

I am pregnant. How is thyroid care different?

Pregnancy needs a tighter TSH target, below 2.5 in the first trimester and below 3.0 later. Levothyroxine dose usually rises by 25 to 50 percent once pregnancy is confirmed and is checked every four to six weeks. In hyperthyroidism, propylthiouracil is preferred in the first trimester, with a switch to methimazole later. We coordinate with your obstetrician.

When should I take my levothyroxine tablet?

Fasting, 30 to 60 minutes before breakfast, with water only. An alternative is at bedtime, at least three hours after the last meal. Pick one time and stick to it, because consistency is what keeps TSH stable.

Which foods and supplements affect levothyroxine?

Coffee, soya, calcium and iron supplements, antacids and proton pump inhibitors all reduce absorption. Take them at least four hours away from your levothyroxine. A high-fibre breakfast straight after the tablet also blunts absorption, which is why fasting is preferred.

Can you refill my home-country thyroid prescription in Patong?

Yes. Bring your most recent TSH result, current dose and brand. We check a fresh TSH if it has been longer than six months, write a Thai prescription, and dispense the same visit. We keep your record on file for future refills.

Will thyroid medication help me lose weight?

Only if you are genuinely hypothyroid. Levothyroxine corrects metabolism back to normal, which typically returns a few kilograms but is not a weight-loss drug. Taking it without a confirmed diagnosis is dangerous, suppresses your own thyroid, and risks atrial fibrillation and osteoporosis.

Sources

American Thyroid Association guidelines | NICE NG145: Thyroid disease assessment and management | European Thyroid Association guidelines

Same-day testing, results within hours: WhatsApp +66 95 073 5550 | Call +66 81 718 9080 | Find us on Maps

Thyroid, TSH, free T4, free T3, anti-TPO, anti-Tg, TRAb, TSI, Hashimoto’s thyroiditis, Graves’ disease, hypothyroidism, hyperthyroidism, levothyroxine, methimazole, propylthiouracil, thyroid nodule, goitre, TIRADS, FNA, thyroid storm, pregnancy thyroid, Patong, Phuket