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Does Levothyroxine Causes Fast Heartbeats?

Posted on Mon, 24 Nov 2014

Question: Had thyroidectomy in May. XXXXXXX after. 200 levothyroxine causes fast heartbeat. Doc switched to 175. Headaches and fast heart beat better. Last blood test and doc said go back on 200. Two days on 200 and not feeling good. Very, very tired and blah. Do I need more time on 200? Should I ask to switch to Synthroid from generic? Maybe natural T3 or T4?

Answered by Dr. Binu Parameswaran Pillai (2 hours later)

Brief Answer:
Last Thyroid function test reports

Detailed Answer:
Good day,
Noted your concern. Sorry to hear about your symptoms. I noted that you had thyroidectomy followed by radio idoine ablation. Did yo have thyroid malignancy?
If so, we try to keep the TSH around 0.1 durig next few years. May i know what was your thyroid blood report while on 200 mcg Synthroid?
Regards
Binu

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

Follow up: Dr. Binu Parameswaran Pillai (24 minutes later)

I don't have those tests with me but will reply with them when I am back in town tomorrow . Yes, there was malignancy. One surgery to remove nodule was done until path reports were done and next morning other side came out due to malignancy .

T4 on 10/22 after two months on 175 levothyroxine was .95
TSH was 4.87

On August 22 after first 60 days on synthetic hormone (200)
T4 was 1.39
TSH was .04

Answered by Dr. Binu Parameswaran Pillai (23 hours later)

Brief Answer:
Keep TSH at around 0.1

Detailed Answer:
Apologies in the delay in reply. I was out of station in the country side and had no access to internet.

Noted your clinical history. With the history of thyroid malignancy, we would like to have the TSH at around 0.1 for the next several years to prevent the recurrence of thyroid cancer. What is your weight and height. I would be able to predict your requirement of Levothyroxine to keep your TSH at around 0.1.

You must also take Calcium ( 500 to 1000 mg) and Vitamin D ( 1000 to 2000 units) a day to protect your bones when you are using such high doses of Levothyroxine

Regards
Binu

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

Follow up: Dr. Binu Parameswaran Pillai (3 hours later)

I am 6'1" and 214 pounds

Answered by Dr. Binu Parameswaran Pillai (7 hours later)

Brief Answer:
Levothyroxine dose

Detailed Answer:
Hello,

Your weight is around 97 kg. We need to keep your TSH around 0.1 for atleast 5 years to reduce the chance of recurrence of malignancy.

You may take Levothyroxine 200 mcg x 5 days a week ( Monday to Friday) and 175 x 2 days ( Saturday and sunday). This is to maintain a level of TSH at around 0.1

Once you have modified the dose, please recheck TSH after 6 to 8 weeks.

You need to improve your calcium and Vitamin D intake as well to protect the bones whilst on high dose levothyroxine.

When is your next iodine whole body scan due ?

Regards
Binu

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

Follow up: Dr. Binu Parameswaran Pillai (7 hours later)

The endo has not indicated any scans. However at last appt. he did an ultrasound and found what may or may not be scar tissue on the thyroid bed. So at this Thursdays appt. I will find out. He indicated it may mean more and stronger XXXXXXX prior to which there would be another WBS I assume?. Thank you. Do you have an opinion about switching to Synthroid from the generic version. Some blog posts indicated there could be profound differences in switching. I'm also very interested in learning about the "natural" hormones that some say worked when the levothyroxine was difficult. Thank you so much. I appreciate your time. I had no idea what our thyroids do but what a lesson I am getting now!

Answered by Dr. Binu Parameswaran Pillai (5 hours later)

Brief Answer:
Synthroid preferred

Detailed Answer:
Yes, swtching can cause trouble initially. But Synthroid would be better. Since you have Thyroid malignancy and we need to fine tune the levothyroxie dose, natural hormones ( armour thyroid) may not be the best option in you
Let me know the detalis once you meet your doc this thursday
Binu

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

Follow up: Dr. Binu Parameswaran Pillai (18 hours later)

Thank you very much. That helps. I will be in touch after Thirsdays appointment and at that appt I will ask the endo about a switch to Synthroid and off the generic. God bless.

Answered by Dr. Binu Parameswaran Pillai (2 hours later)

Brief Answer:
Good luck

Detailed Answer:
Wish you good health.

Note: For further queries related to coronary artery disease and prevention, click here.

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar