My tsh shows 5.91 uiu/ml? what does it mean? and how can i treat myself? i am 48 years old.

Hypothyroid: Your thyroid gland is no working. You need to be on thyroid medication. There is nothing you can do at home. This is actually the most common medical condition in medicine.

High TSH: Your TSH is higher than normal (2.5 would be considered upper level, although, in some countries such as uk, it is raised to 4.5). Nonetheless, it's higher than normal. This indicates that your thyroid function is lower than normal (it's a reverse relation). At this level, i don't necessarily treat especially if symptoms of low function are not present. May repeat in 3 months.

You have : Hypothyroidism, and you can't treat yourself. You need to have your doctor start you on brand name T4 replacement, and then check levels every 6 weeks and readjust dose until appropriate. After that, it's just a once/year check. You'll be on the medication life-long, but it's easy, cheap and safe.