Hi
I'm currently undermedicated. Could that be the cause?
Hello and hope you are doing well.
Check your thyroid status. If there is excess of thyroxine (Synthroid), it can cause adverse effects like; tremor, anxiety, muscle weakness, nausea, vomiting and diarrhea to name a few. In addition its effects on the heart cause palpitations and arrhythmias. The thyroid status can fluctuate from hyper to hypothyroidism; you could repeat your thyroid profile to know the current status of your thyroid gland. You have to ensure to take your medications regularly and you have to monitor the levels of your thyroid status at least once in three months.
Hope this helped and do keep us posted.