What should you know about TSI and hyperthyroidism?

Thyroid-stimulating immunoglobulins can attach to the thyroid's TSH receptors and act like a signal to make thyroid hormone. A positive TSI result may support Graves disease, particularly when thyroid tests and symptoms show an overactive pattern. It does not by itself measure hormone levels, show how severe symptoms are, or replace a clinical assessment. Hyperthyroidism may also have causes that do not involve TSI. Symptoms can include palpitations, excessive sweating, heat intolerance, difficulty sleeping, feeling anxious, diarrhoea, or night sweats.

Review the result with a clinician alongside TSH, free T4, T3, medicines, examination findings, and any previous tests. Ask how the result affects the working diagnosis and treatment plan. Take prescribed medicine exactly as directed and report new or worsening symptoms. If you are pregnant, planning pregnancy, or have eye symptoms such as pain, redness, or double vision, mention this promptly because it can affect assessment and treatment choices.

Seek emergency help for chest pain, fainting, severe breathlessness, confusion, or a very fast or irregular heartbeat. Contact your clinician promptly if palpitations, sweating, tremor, diarrhoea, or sleep problems are becoming more intense, or if new eye symptoms appear.

Ask what the TSI result means with your thyroid hormone results, whether further antibody or imaging tests are useful, and how treatment will be monitored. Ask which symptoms require urgent review and whether eye assessment is appropriate.