What You Need to Know About Hypothyroidism

Understanding what hypothyroidism means
Hypothyroidism occurs when your thyroid gland does not produce enough thyroid hormone. Because thyroid hormone influences metabolism, energy, heart function, temperature control, and many body systems, low levels can slow the body down. Symptoms often develop gradually, so they may be mistaken for stress, ageing, or lifestyle factors.

Common symptoms you may notice
You may experience tiredness, low energy, or weight gain despite normal eating. Many people feel unusually sensitive to cold, develop dry skin, hair thinning, brittle hair, or constipation. Heavy or irregular menstrual bleeding, low mood, slowed thinking, and “brain fog” are also common. Symptoms often build slowly over months.

Other possible signs to be aware of
Some people develop a neck swelling called a goitre. Others may experience slowed heart rate, puffiness around the eyes, muscle aches, fertility concerns, or changes in voice. Children and teenagers may show growth or development changes. Pregnant women with thyroid disease need specific medical care because thyroid levels influence pregnancy health and fetal development.

What causes hypothyroidism
Common causes include autoimmune thyroid disease such as Hashimoto’s thyroiditis, previous thyroid surgery or treatment, iodine imbalance, or medication-related causes. Risk depends on age, family history, medical history, and other health conditions. Diagnosis relies on testing, not assumption.

How hypothyroidism is diagnosed and treated
Diagnosis is based on blood tests measuring thyroid hormone levels and thyroid stimulating hormone (TSH). Your GP may arrange further tests if needed. Treatment usually involves thyroid hormone replacement to restore healthy levels. Many people feel better gradually over weeks to months. Ongoing monitoring is important to keep levels stable and safe.

Myths vs Reality
“I will feel better instantly once treatment starts.” Improvement can take time. Many people feel gradual benefit as hormone levels stabilise.
“Weight gain always disappears with treatment.” Treatment helps restore hormone balance, but healthy lifestyle support still matters. Weight changes vary.
“Hypothyroidism always causes severe symptoms.” Some people feel very unwell; others have subtle or minimal symptoms. Testing clarifies the picture.
“Once I start medication, I can adjust it myself.” Self-adjusting is unsafe. Dose changes require medical guidance and monitoring.

Australian care pathway and specialist referral
In Australia, your GP usually leads initial assessment, diagnosis, and treatment. Many people are safely managed in general practice with regular follow-up. Referral to an endocrinologist may be recommended if diagnosis is unclear, symptoms remain despite treatment, thyroid levels are difficult to stabilise, pregnancy or fertility concerns exist, or complex autoimmune or structural thyroid disease is present. Shared care between GP and specialist helps ensure safe, coordinated management.

Lifestyle, medication adherence, and follow-up
Thyroid medication works best when taken consistently, usually once daily and ideally on an empty stomach as advised by your doctor. Missing doses or stopping medication suddenly can affect your health. Regular blood tests support safe dose adjustments. Healthy eating, adequate sleep, stress management, and managing other health conditions also support wellbeing. Always speak with your doctor before taking supplements or new medicines, as some can affect thyroid levels.

When to see your GP
See your GP if you experience persistent fatigue, unexplained weight change, cold intolerance, mood change, menstrual change, or new neck swelling. Seek urgent care for severe neck swelling, difficulty breathing, fainting, or severe chest pain. Early review supports clarity, reassurance, and safer care.

This article provides general health information only and does not replace medical advice. Please speak with your GP for personalised care.