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Related to underactive: underactive bladder, Underactive thyroid


Characterized by insufficient or abnormally low activity: an underactive area of the brain.

un′der·ac·tiv′i·ty (-ĭ-tē) n.


1. not sufficiently active
2. (Medicine) med (of the thyroid or adrenal glands) not functioning at full capacity


(ˌʌn dərˈæk tɪv)

insufficiently active: an underactive thyroid gland.
un`der•ac•tiv′i•ty, n.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.underactive - abnormally inactiveunderactive - abnormally inactive      
inactive - not active physically or mentally; "illness forced him to live an inactive life"; "dreamy and inactive by nature"
References in periodicals archive ?
If you have an underactive thyroid, you'll need to take a thyroid hormone for the rest of your life.
Reversible causes include: depression and anxiety, vitamin B12 deficiency, infections, delirium, surgery, certain medications, underactive thyroid gland and head injury or tumours.
If a patient suffers from an underactive thyroid, he or she is likely to experience excessive tiredness, unexplained weight gain, feeling cold, constipation, and increased sleep, puffiness under the eyes and aches and pains.
Common symptoms, similar to an underactive thyroid, are feeling tired, mood swings, weight gain, heart palpations, sweating and lighter periods.
It gave me the chance to bring it under control by taking the right level of thyroxine medication - I take one 75mcg tablet daily, which prevented my underactive thyroid causing problems for my baby.
A blood test confirmed hypothyroidismher thyroid gland was underactive, producing too little thyroid hormone.
For instance, "if you look at anorexics, their thyroid pattern can be confused with an underactive thyroid," Garber said in a phone interview.
Make an appointment with your GP who may suggest you have a blood test to rule out a medical cause such as anaemia or an underactive thyroid gland.
With the help of dyes to distinguish the signals from the left and right eyes, they saw in postmortems that microglia had preferentially pruned the connections, or synapses, from circuits serving the underactive eye.
While her peers bemoan their underactive thyroid, or blame their weight issues on the trials and tribulations of public life, the actress has been remarkably candid about life before she lost an incredible eight stone.
Numerous studies since 1999 have found that an underactive thyroid can raise a woman's risk of miscarriage, premature birth, or a lower IQ for her baby - even if it's so mildly sluggish that she feels no symptoms.