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Does Large Doses Of Levothyroxine Cause Tiredness And Low Heart Rate?
Question: Hi i have been taking higher doses of levothyroxine that i was prescribed for for about three weeks now because i was sooooo tired all the time so i figured if i increase my dose that may help I have lost weight by now .In the beginning my hearts rate was fast but i am now even more tired than before and my heart rate is very low despite the levothyroxine higher dosage and drinking coffe or red bull.... Is that something unusuall?
Brief Answer:
Hello
Detailed Answer:
Hello,
Good day.
It is wrong to take large doses of levothyroxine. It is dangerous and can precipitate abnormal heart beats etc. It is defenitely not recommended to use high doses of levothyroxine for weight loss. The dose should be just enough to keep your TSH in mid normal range and your Free T4 ( FT4) in the upper half of normal range.
What is your heaight and weight?
What is your heart rate now. It is difficult to assess the heart rate unless i examine you. It is unusual to have a low heart beat whilst on a big dose of levothyroxine. A doctor need to examine your pulse and an ECG may be required before advising further
Regards
Binu
Hello
Detailed Answer:
Hello,
Good day.
It is wrong to take large doses of levothyroxine. It is dangerous and can precipitate abnormal heart beats etc. It is defenitely not recommended to use high doses of levothyroxine for weight loss. The dose should be just enough to keep your TSH in mid normal range and your Free T4 ( FT4) in the upper half of normal range.
What is your heaight and weight?
What is your heart rate now. It is difficult to assess the heart rate unless i examine you. It is unusual to have a low heart beat whilst on a big dose of levothyroxine. A doctor need to examine your pulse and an ECG may be required before advising further
Regards
Binu
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
my heart rate in the morning was 63 but it is usually way higher especiially in the evenings than that plus i am dizzy and have nausea and instead of being hot after levothyroxine i have actually episodes of being cold and have chills....along with some chest pain on my left site only but my heart should be fast beating after doses of 176 mcg or 264 a day instead of 88 correct? i drink red bull coffee and i just become more week and my heart rate is not up to speed as i thought it would be...plus i dont know if it has anything to do with that but the skin on my foot just cracked open....I weight around 143 right now My height 5'9
Brief Answer:
Hi
Detailed Answer:
Hello,
If you have measured your heart beat correctly and if it counted 63 whilst on a high dose levothyroxine, then it is low. Are you on a beta blocker or any other drug which can lower your heart rate ( eg: Atenolol, propranolol, digoxin, verapamil, diltiazem etc?). If you are on any of these pills, your heart rate will not rise despite being on a hogh dose levothyroxine.
Howver, other symptoms which you mentioned are signs of excess thyroid medications. 264 mcg instad of 88 mcg is a huge dose especially for some one f your weight. I msut say that redbull and coffee are caffeine rich and either of them in large quantities is not good. Besides, they cotain good amount of calories and can cause weight gain. I am doubtful if the foot crack has any relation to thyroid or thyroid medications.
Regards
Binu
Hi
Detailed Answer:
Hello,
If you have measured your heart beat correctly and if it counted 63 whilst on a high dose levothyroxine, then it is low. Are you on a beta blocker or any other drug which can lower your heart rate ( eg: Atenolol, propranolol, digoxin, verapamil, diltiazem etc?). If you are on any of these pills, your heart rate will not rise despite being on a hogh dose levothyroxine.
Howver, other symptoms which you mentioned are signs of excess thyroid medications. 264 mcg instad of 88 mcg is a huge dose especially for some one f your weight. I msut say that redbull and coffee are caffeine rich and either of them in large quantities is not good. Besides, they cotain good amount of calories and can cause weight gain. I am doubtful if the foot crack has any relation to thyroid or thyroid medications.
Regards
Binu
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
I am not on any medicine that would lower my heart rate that is why i am so confused....plus as i mentioned .... i thought higher doses of levothyroxine would make me hot not cold.... I tend to loose potassium from time to time for no apparent reason maybe that is what is going on ? Would that explain the heart rate even after taking higher dose of Levothyroxine since i had some diarrhea i few days in a row right after i started taking the higher dose?
Brief Answer:
hi
Detailed Answer:
High dose of levothyroxine can cause diarrhea and in that way you may lose potassium. Besides , hyperthyroidism by itself can cause low blood potassium. Low potassium usually cause irregular heart beats or arrhythmia. However it doesn't seem to be the cause of slow heart rate I'm your case. However pulse rate of 63 is not very low. But that is low for someone who is on high dose levothyroxine. Get your pulse checked by another person preferably a doctor
.regards
B
hi
Detailed Answer:
High dose of levothyroxine can cause diarrhea and in that way you may lose potassium. Besides , hyperthyroidism by itself can cause low blood potassium. Low potassium usually cause irregular heart beats or arrhythmia. However it doesn't seem to be the cause of slow heart rate I'm your case. However pulse rate of 63 is not very low. But that is low for someone who is on high dose levothyroxine. Get your pulse checked by another person preferably a doctor
.regards
B
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Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
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