Many symptoms of an underactive thyroid (hypothyroidism) are the same as those of other conditions, so it can easily be confused for something else.
Symptoms usually develop slowly and you may not realise you have a medical problem for several years.
Common symptoms include:
tiredness
being sensitive to cold
weight gain
slow movements and thoughts
muscle aches and weakness
muscle cramps
dry and scaly skin
brittle hair and nails
pain, numbness and a tingling sensation in the hand and fingers (carpal tunnel syndrome)
irregular periods or heavy periods
Elderly people with an underactive thyroid may develop memory problems and depression. Children may experience slower growth and development. Teenagers may start puberty earlier than normal.
If you have any of these symptoms, see your GP and ask to be tested for an underactive thyroid.
Read more about getting tested for an underactive thyroid.
If an underactive thyroid isn’t treated
It’s unlikely that you’d have many of the later symptoms of an underactive thyroid, because the condition is often identified before more serious symptoms appear.
Later symptoms of an underactive thyroid include:
a low-pitched and hoarse voice
a puffy-looking face
thinned or partly missing eyebrows
a slow heart rate