on the other hand, if you have no symptoms, some doctors would be prepared to monitor (ie. test again in 3 -6 months) rather than start treatment. Some doctors only treat if TSH is 10 or higher.
But generally, if you have symptoms, and/or if your FT3 and Ft4 were at lower end of range or below, and/or if you had antibodies the approach would be to start you on a low dose of thyroid meds.
You need to find out what's causing this high TSH. Yes, if hypothyroidism is left untreated, you could end up very unwell. You don't want to go down that road, trust me. I've been there.
Please get your TGab and TPOab blood tests to determine if Hashimoto's is the cause of your high TSH. Also, get a thyroid ultrasound to determine if you have nodules/goiter.
Get your FT4 and FT3 tests to see your current level of thyroid hormone, so that you can get proper treatment.
Patients have many alternatives for treating hypothyroidism from synthetics like Synthroid, Levo and Cytomel to the natural dessicated drugs like Armour and Nature-Throid.
If you don't get treatment, your TSH could go higher, and if you have any fatigue, dry skin, constipation, depression, hair loss, pain, etc, it will worsen.
:) Tamra