The short explanation
It could be an overactive thyroid, which speeds the body up: a fast or irregular heartbeat, shaky hands, feeling hot and sweaty, weight loss despite eating, anxiety or irritability, loose stools and lighter periods. It is less common than an underactive thyroid but it is important to find, because untreated it strains the heart and bones. A blood test is the first step. These symptoms also have other causes, including anxiety, anaemia and some medicines, which is another reason to test rather than guess.
What depends on your situation
The parts of this that change from woman to woman. Uncertainty is stated, not hidden.
- Common causes include Graves' disease, an autoimmune condition that can also affect the eyes, and nodules that make too much hormone. Short-lived overactivity also happens after pregnancy or a viral infection. Treatment depends on the cause and usually involves an endocrinologist.
- If you are pregnant or planning to be, say so — it changes which treatments are used.
What this answer cannot determine
The boundary of online education. These need a clinician who can see you.
- This cannot tell you whether your thyroid is overactive or why, and it cannot suggest a treatment. A palpitation that feels like thyroid can be something else entirely.
Questions for your clinician
Take these with you. You can add any of them to an appointment card.
- Can we test my thyroid, and what else could explain these symptoms?
- If it is overactive, what is causing it?
- What are the treatment options, and how do they affect pregnancy plans?
- Do my eyes need checking?
When to seek help
Clinician-approved guidance for this topic. When in doubt, being seen is never the wrong choice.
- Get emergency care now (call 112 or 108) for chest pain, fainting, severe breathlessness, a very fast heartbeat with confusion or high fever, or a heartbeat that will not settle.
- See a clinician within days for a racing heart, tremor and weight loss that have developed over weeks, or for eyes that have become red, gritty, bulging or painful, or double vision.
Sources
The evidence this explanation is built on.
- Overactive thyroid (hyperthyroidism) NHS
- Hyperthyroidism MedlinePlus (NIH)
Who wrote and reviewed this
Every AskHer answer names its author. A clinically reviewed answer also names the clinician who signed it off — if no clinician is named below, it has not been clinically reviewed.
- Author
- AskHer Editorial (AI-assisted draft) AskHer's editorial team — not an individual clinician Works in English, தமிழ், हिन्दी
- Clinical reviewer
- Nobody yet No clinician has signed this answer off, and no person on the editorial team has read it yet. That is what the “Written with AI assistance” label means. It is queued for an editor to read, and then for a clinician who works in this area. The sources it was drafted against are listed above.
- Review status
- Written with AI assistance — not yet reviewed by a person
- Last reviewed
- Not yet reviewed by a person
- Version
- 1
Correction history
Substantive changes are listed, not quietly edited away.
No corrections have been made since this answer was first published.
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