Overview
It's more common in women and after age 60.
It comes on slowly, so symptoms can be missed.
Symptoms
Common signs:
- Tiredness and weight gain
- Feeling cold
- Always feeling cold
- Fatigue
Less common
- Dry skin
- Constipation
- Hair thinning
- Low mood
When to get medical care
Causes
Autoimmune disease, thyroid surgery, radiation, some medicines.
Does it spread or run in families?
- It isn't contagious. You can't catch it from someone else.
- It can run in families. Tell your doctor if a parent, brother, or sister has it.
Who is more likely to get it
- Women
- Over 60
- Family history
Possible complications
Diagnosis
A blood test finds it.
Questions you may be asked
- Family history
- Pregnancy
The exam
A neck check.
Tests
Tests, if needed:
- TSH and free T4:
Treatment
Take thyroid medicine the right way.
Self-care
- Take it on an empty stomach, same time daily
- Keep it 4 hours from iron, calcium, and antacids
- Get blood tests as advised
Medicines
Medicines that may help:
| Medicine | Helps with | Good to know |
|---|---|---|
| Thyroid hormone | Replacing hormone | Too much causes a racing heart. |
OwieClear doesn't give doses: follow the label or your healthcare professional. Medicine names here are examples, not a full list.
Prevention
It can't be prevented.
Which doctor treats this
- Start with your primary care provider (family doctor or internist).
- They may send you to an endocrinologist (hormone doctor).
Living with it
- Take thyroid pills the same way every day, often on an empty stomach.
- Get blood tests as advised.
- Long-term illness can affect mood. Tell your doctor if you feel down or anxious.
Support groups and helplines
- American Thyroid Association: Patient guides and support group finder.
Back to school, work, or sports
- Most people can keep working or going to school.
- Ask about changes that help, like extra breaks or a flexible schedule. Workers may be covered by the ADA. Students may get a 504 plan.
Children, pregnancy, and older adults
- Pregnancy: Dose often needs to go up; tell your doctor right away.
Pregnancy and breastfeeding
- If you're pregnant or planning to be, tell your prenatal provider about this condition.
- This condition needs closer checkups during pregnancy. Plan ahead with your doctor.
- Don't start or stop any medicine on your own. Some are safe in pregnancy and some need to be changed.
- Ask before taking any pain reliever. The FDA advises avoiding ibuprofen and naproxen after 20 weeks unless your doctor says to.
- Breastfeeding: Most medicines are fine, but ask. The NIH LactMed database lists what's known about each one.
For caregivers
- Go to visits when you can and take notes.
- Keep a list of medicines, allergies, and doctors in one place.
- Learn the warning signs that need fast care.
- Take breaks and ask for help. Caregivers need care too.
Outlook
Well controlled with medicine.
Myths and facts
Myth: Thyroid problems always cause weight gain.
Fact: Weight changes are usually small. Many other things affect weight.
Getting ready for your visit
Bring a list of your symptoms and medicines.
Questions to ask
- How often should I be tested?
Research studies
Research studies test new ways to find and treat health problems. Some are looking for volunteers. Talk with your doctor before joining one.
Search ClinicalTrials.gov for studies on Underactive thyroid (hypothyroidism)
Sources
Last updated 2026-11-12.