Private thyroid disorders clinic in London, same-day endocrinology.

Underactive thyroid

• tiredness that sleep does not fix, and feeling cold when others are not
• weight gain despite no change in eating, and constipation
• dry skin, brittle nails, hair thinning, loss of the outer eyebrow
• low mood, poor memory and concentration, slowed thinking
• heavy or irregular periods, and difficulty conceiving
• muscle aches, cramps, and a hoarse voice

Overactive thyroid

• weight loss despite a good or increased appetite
• palpitations, a racing or irregular pulse, tremor
• anxiety, irritability, restlessness, difficulty sleeping
• feeling hot, sweating excessively, heat intolerance
• frequent or loose bowel movements
• muscle weakness, particularly climbing stairs; eye changes in Graves' disease

Taking levothyroxine properly

• Take it on an empty stomach, ideally 30 to 60 minutes before breakfast, or at bedtime at least two hours after eating.
• Take it at the same time every day, with water.
• Separate it by four hours from iron, calcium, indigestion remedies and multivitamins, all of which block absorption. This is the commonest reason a dose seems not to work.
• Recheck blood tests six to eight weeks after any dose change — earlier is uninterpretable.
• It is a replacement, not a stimulant. It will not cause weight loss beyond correcting the deficiency, and taking more than you need causes palpitations, anxiety and bone thinning.
• Requirements rise in pregnancy, often substantially and early — tell us as soon as you have a positive test.

Thyroid lumps

Thyroid nodules are extremely common and the great majority are benign. They are assessed with thyroid function tests, ultrasound, and a fine needle sample where the ultrasound features warrant it. A lump that is hard, fixed, rapidly growing, associated with a hoarse voice or with swollen neck glands needs urgent assessment.

When to think of the thyroid

Ask for a test if you have unexplained fatigue, weight change, palpitations, low mood, hair loss, irregular periods, infertility, recurrent miscarriage, or a family history of thyroid or autoimmune disease. It is also worth checking before attributing symptoms entirely to the perimenopause, since the two overlap almost completely and frequently coexist.