Thyroid hormones are needed by pretty much every cell in your body for them to function properly. If you are not able to tolerate your meds, you need to see your doctor ASAP to discuss alternative meds.
How and when are you taking your Synthroid? Time of day, with or without food...other meds?
We need more info from you. Please post your thyroid test results and their reference ranges shown on the lab report. Was the cause of your hypothyroidism ever diagnosed? What are the different thyroid meds that you have taken?
Until members have more info, and can perhaps make a better recommendation, I would advise that you start taking the thyroid meds again. If your body needs supplemental thyroid meds like that, then going without thyroid med is not an option. If your levels of thyroid hormone get too low it can be devastating for you.