Mayo Clinic
mayoclinic.org › drugs-supplements › levothyroxine-oral-route › description › drg-20072133
Levothyroxine (oral route) - Side effects & dosage - Mayo Clinic
October 1, 2025 - Levothyroxine should not be used for the treatment of obesity or for the purpose of losing weight. This medicine is not effective for weight reduction.
GoodRx
goodrx.com › goodrx health › drugs › levothyroxine › levothyroxine dosage based on age and body weight
Levothyroxine Dosage Based on Age and Body Weight - GoodRx
September 13, 2024 - It’s recommended to only change the dose by 12.5 mcg to 25 mcg at a time. Once your TSH levels have stabilized, you’ll likely only need it tested once every 6 to 12 months. ... dosage for children depends on their age and body weight, as ...
Weight loss and medication adjustment?
Yes, generally your Levo need will change based on your weight so significant weight changes may require dosage changes too. You should mention both the weight changes and your symptoms to your Endo who may run labs to check how your levels look. And then always important to mention it’s also possible your symptom isn’t related to your hormones or ThyCa, so if your doctor rules that out based on labs you’d need to investigate other possible causes with your primary care doctor. Dizziness and vertigo can have lots of other causes too. More on reddit.com
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April 6, 2024Has Anyone tried to use Levothyroxine to loose weight or manage their weight?
Levothyroxine is a hormone supplement babes. It's like taking insulin. If you give your body more than it needs, it's going to have unwanted side effects. You should try ozempic or similar drugs for weight-loss, NOT a literal hormone. More on reddit.com
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August 16, 2024Did anyone lose weight after starting levothyroxine?
It had no impact on my weight. More on reddit.com
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May 15, 2023Why am I losing so much weight after levothyroxine?
Still waiting for that to kick in for me, lol. Just upped from 50 to 75. An underactive thyroid can cause you to gain weight, so if you rectify that by taking thyroid medication, you will lose the weight you gained previously. Nothing to worry about and you won't drop weight forever. It is just resetting you to where you would have been if your thyroid hadn't stopped working properly. Keep monitoring it and if you are concerned, talk to your doctor. More on reddit.com
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December 25, 2021American Thyroid Association
thyroid.org › home › patients portal › clinical thyroidology for the public › june 2018 › vol 11 issue 6 p.5-6
Body weight appears to be the main levothyroxine dose adjustment variable
June 9, 2018 - They each took a single dose of radioactive labeled Levothyroxine after 8 hours of fasting, followed by breakfast 2 hours later. The radioactive labeled thyroid hormone made it possible for the researchers to measure and follow the blood level of the dose taken by each study subject. Patients had blood tests before taking the dose and in regular intervals up to 312 hours after the dose. The results were compared between the participants based on their sex, age and weight.
BuzzRx
buzzrx.com › blog › is-100-mcg-of-levothyroxine-a-high-dose
Levothyroxine Dosage Guide: What’s Considered Low, Normal, or High?
September 29, 2025 - Get clear answers on levothyroxine dosage. Learn what’s considered low, normal, or high—from 25 mcg to 200 mcg—to better understand your prescription.
American Academy of Family Physicians
aafp.org › pubs › afp › issues › 2006 › 0401 › p1271.html
Levothyroxine Starting Dose in Primary Hypothyroid Treatment | AAFP
April 1, 2006 - Patients were excluded if they had a history of cardiac disease or were taking cardiac medication. Patients were randomly assigned to receive a starting levothyroxine dosage of 25 mcg per day (low dose) or ...
NCBI
ncbi.nlm.nih.gov › books › NBK539808
Levothyroxine - StatPearls - NCBI Bookshelf
August 28, 2023 - Boxed Warning: Levothyroxine or other thyroid hormones, alone or with other therapeutic drugs, should not be used to treat obesity or promote weight loss. In euthyroid patients, levothyroxine dose in the range of daily hormonal requirements is ineffective for weight loss.
NHS
nhs.uk › medicines › levothyroxine
Levothyroxine: a medicine for an underactive thyroid (hypothyroidism) - NHS
However, if you have side effects such as headaches, flushing or sweating with levothyroxine, alcohol may make these worse. ... One of the symptoms of an underactive thyroid gland is weight gain. So, once you start taking levothyroxine, you may lose weight as your body's hormones rebalance.
MedlinePlus
medlineplus.gov › home › drugs, herbs and supplements
Levothyroxine: MedlinePlus Drug Information
Levothyroxine (a thyroid hormone) should not be used alone or along with other treatments to treat obesity or cause weight loss.
American Thyroid Association
thyroid.org › home › patients portal › clinical thyroidology for the public › august 2019 › vol 12 issue 8 p.7-8
Levothyroxine dose may change after weight loss surgery in patients with hypothyroidism
August 8, 2019 - At 24 months after bariatric surgery, ... average weight-based daily levothyroxine dose was unchanged (1.15 mcg/kg/ day before surgery and 1.11 mcg/kg/day after surgery)....
FDA
accessdata.fda.gov › drugsatfda_docs › label › 2019 › 021116s017lbl.pdf pdf
levothyroxine sodium tablets - accessdata.fda.gov
Levothyroxine Sodium Tablets dosage ... and symptoms of hypothyroidism, start Levothyroxine Sodium Tablets at · the full replacement dose (1.6 mcg per kg body weight per day)....
HealthCentral
healthcentral.com › condition › hypothyroidism › levothyroxine-weight-gain
Levothyroxine and Weight Gain: How to Manage Weight
September 15, 2022 - One study of 101 people with hypothyroidism found that 52% lost weight after starting treatment with thyroid hormone replacement, with an average loss of 8.4 pounds. Researchers concluded that “contrary to popular belief,” starting medication results in “no significant weight change.” (On the other hand, losing even a little bit of weight is better than losing none in terms of benefitting your overall health.) Levothyroxine is a synthetic form of the hormone thyroxine, or T4, and the most commonly used medication for underactive thyroid.
Synthroid
synthroid.com › taking-synthroid
How to Take Synthroid the Right Way
SYNTHROID® (levothyroxine sodium) tablets, for oral use is a prescription, man-made thyroid hormone that is used to treat a condition called hypothyroidism in adults and children, including infants. It is meant to · Thyroid hormones, including SYNTHROID, should not be used either alone or in combination with other drugs for the treatment of obesity or weight loss...
Drugs.com
drugs.com › home › levothyroxine › faq
Does levothyroxine cause weight gain or loss?
August 26, 2024 - In most cases, levothyroxine causes some weight loss. According to the American Thyroid Association, when this medication is started, you may lose up to 10% of your weight.
Endocrinologyadvisor
endocrinologyadvisor.com › home › news › levothyroxine dose adjustment after bariatric surgery weight loss
Levothyroxine Dose Adjustment After Bariatric Surgery Weight Loss - Endocrinology Advisor
May 22, 2024 - “The present study shows that in hypothyroid patients with morbid obesity, after BS-induced weight loss, the total LT4 dose or the LT4 dose/kg ideal body weight did not change, although there was a significant increase in LT4 dose/[body surface area], LT4 dose/kg actual weight, LT4 dose/kg adjusted body weight, LT4 dose/kg body fat, and LT4 dose/kg lean body weight,” according to the researchers, adding that the study “strongly suggests that thyroid-stimulating hormone in obese hypothyroid patients can be individually adapted more precisely if it is based on ideal body weight.”
Drugs.com
drugs.com › home › levothyroxine › dosage
Levothyroxine Dosage Guide + Max Dose, Adjustments - Drugs.com
February 6, 2024 - Thyroid hormones, either alone or with other agents, should not be used for the treatment of obesity or for weight loss. In euthyroid patients, doses within the range of daily hormonal requirements are ineffective for weight reduction.
ScienceDirect
sciencedirect.com › science › article › pii › S2214623721000168
Appropriate dose of levothyroxine replacement therapy for hypothyroid obese patients - ScienceDirect
July 30, 2021 - Athyreotic patients require a daily levothyroxine (LT4) doses of 1.6–1.8 mcg/kg of actual body weight (BW) to achieve normal thyroid stimulating hormo…
Reddit
reddit.com › r/thyroidcancer › weight loss and medication adjustment?
r/thyroidcancer on Reddit: Weight loss and medication adjustment?
April 6, 2024 -
Hi-I had a TT ten years ago due to what was called a “malignancy” in a thyroid module, diagnosed after a partial TT. My levothyroxine dose started at around 125mg, but the dose has been gradually decreased by my medical providers over the years and I am now taking only 75 mg daily. I struggled with weight gain since the TT, but as I approached age 60 this year, decided to try weight loss medication along with regular strength training to really try to lose the weight. I started Wegovy in March and I am down 40 pounds (160 to 120). I have recently been experiencing dizziness, not like the “I am about to faint” kind, more like vertigo. I eat well, lots of protein most days, etc, so I don’t think lack of nutrition is the issue. I am wondering if the levothyroxine dose may have to be adjusted again because of the weight loss and maybe this is the reason for the dizziness. Just wondering what other people’s experiences have been with weight fluctuations and needing to adjust thyroid replacement meds.
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Yes, generally your Levo need will change based on your weight so significant weight changes may require dosage changes too. You should mention both the weight changes and your symptoms to your Endo who may run labs to check how your levels look. And then always important to mention it’s also possible your symptom isn’t related to your hormones or ThyCa, so if your doctor rules that out based on labs you’d need to investigate other possible causes with your primary care doctor. Dizziness and vertigo can have lots of other causes too.
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Yes! Levothyroxine dosing can change quite a bit based on weight. I’ve lost 40 lbs so far on semaglutide (220 to 180 lbs) and my dose has changed from 175 mcg 8x/week to 175 mcg 5x/week, with more frequent TSH bloodwork to make sure I’m in range as I lose weight.
SingleCare
singlecare.com › home › does levothyroxine cause weight gain?
Does levothyroxine cause weight gain? What to know
October 20, 2025 - Your provider can run a panel of standard blood tests that check for normal thyroid function. Normal TSH values are between 0.5 and 5.0 mIU/L. When your results fall within the normal ranges, that means levothyroxine is doing its job and should not cause weight gain or hinder weight loss.
Mayo Clinic
mayoclinic.org › drugs-supplements › levothyroxine-injection-route › description › drg-20072053
Levothyroxine (injection route) - Side effects & dosage - Mayo Clinic
October 1, 2025 - Check with your doctor right away if you have more than one of these symptoms: chest pain, decreased urine output, dilated neck veins, extreme fatigue, irregular breathing, irregular heartbeat, swelling of the face, fingers, feet, or lower legs, tightness in the chest, trouble breathing, or weight gain. Levothyroxine should not be used for the treatment of obesity or for the purpose of losing weight.
Verywell Health
verywellhealth.com › too-much-thyroid-medication-3233271
Signs You're Taking Too Much Levothyroxine for Your Thyroid
December 9, 2025 - Taking too much levothyroxine for an underactive thyroid can inadvertently push your body into a hyperthyroid state, causing symptoms like rapid heartbeat, anxiety, and weight loss.