Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
1
Is any of this happening now?
Call 911
Seek emergency medical help for:
Sudden or rapidly worsening muscle weakness
Inability to stand, walk, or lift the limbs
Trouble breathing, speaking, or swallowing
Fainting, chest pain, or a fast or irregular heartbeat
Weakness after a previous episode of thyrotoxic periodic paralysis
Do not take extra potassium in an attempt to correct the problem unless emergency clinicians or an established care plan instruct you to do so.
And for anyone, someone who:
is bleeding heavily and it will not stop with firm pressure
Other emergency signs, for anyone
Someone who is struggling to breathe, gasping, choking, or cannot get words out
Someone who has chest pain, tightness or pressure lasting more than a few minutes
Someone who has sudden weakness or drooping on one side of the face or body, slurred speech, or sudden confusion
Someone who is unconscious, or cannot be woken
Someone who has had a seizure that will not stop, or does not wake up afterwards
Someone who has lips or skin that look pale, blue, grey or blotchy
Someone who you believe has taken an overdose or swallowed something poisonous
2
Is any of this happening?
Be seen today
Arrange prompt medical assessment if you develop possible symptoms of thyroid overactivity, such as persistent palpitations, unexplained weight loss, tremor, sweating, or heat intolerance, even without weakness.
Contact your usual care team sooner if thyroid symptoms return or prescribed treatment is interrupted.
3
Does any of this apply?
Book an appointment
Routine follow-up is needed after an attack to check thyroid hormone levels, review treatment, and confirm that potassium has remained normal.
The article also says
Do not drive yourself if your legs or arms are weak.
Every sign above is quoted from the sofidex article on Thyrotoxic periodic paralysis. If you are not sure, err upward — it is always reasonable to be checked.