An underactive thyroid gland is a surprisingly common condition, affecting up to 5 percent of adult Americans. More people experience subclinical hypothyroidism than overt hypothyroidism. Nonetheless, plenty of folks suffer with troublesome symptoms such as fatigue, cold intolerance, puffiness around the eyes, constipation, dry skin, hair loss, muscle or joint pain and depressed mood. Although doctors usually consider hypothyroidism to be simple to diagnose and treat, our readers often report that their experience differs. Delays in diagnosis and difficulty finding the correct dose or the best treatment can be frustrating. Which medication is best? Then there are conflicting instructions about when to take the medication: first thing in the morning, but not with coffee or breakfast. What about taking Synthroid in the middle of the night? Some readers have decided that is the best way to address the dilemmas.
Learning More About Synthroid Interactions:
Q. I’ve been treated for hypothyroidism for close to 40 years. Surprisingly, even now I’m learning new things about it.
After several years of trial and error along with a long series of ultrasensitive TSH tests and avoiding certain foods, my thyroid hormone levels have stabilized. We no longer have to increase my dose of Synthroid on a regular basis.
My doctor suggested leaving a four-hour window before and after taking Synthroid when consuming calcium or soy. Otherwise, they might affect levothyroxine absorption. Lesser known are the effects of grapefruit and walnuts, which should be avoided.
I take my pill when I get up in the middle of the night to go to the bathroom. This disrupts my sleep, but it means less problems with my diet.
A. You might be able to sleep better if you took your Synthroid pill at bedtime. Studies have shown that the results are similar to taking the medicine first thing in the morning, half an hour before coffee and breakfast (Expert Review of Clinical Pharmacology, March 2024). Although you did not mention it, coffee and tea can both interfere with levothyroxine (Synthroid) absorption (Pharmaceuticals, March 2, 2021; Frontiers in Endocrinology, Sep. 12, 2022).
The only reference we could find to walnuts is very old (Endocrinology, March 1970). These researchers consider it a goitrogen, similar to cabbage, collards and broccoli. Excessive amounts of goitrogens interfere with thyroid hormone function. Most people can consume moderate amounts occasionally without upsetting their hormone balance.
You can learn more about foods and supplements that may interfere with levothyroxine absorption in our eGuide to Thyroid Hormones.
Taking Synthroid in the Middle of the Night:
Q. I read that you should wait at least an hour after taking Synthroid before you drink coffee or eat breakfast. To get around this restriction, I take my Synthroid when I get up in the middle of the night to go to the bathroom.
A. Your solution is sensible for those who consistently rise at that time. Some people take their levothyroxine before bed to accomplish the same goal. That way they don’t have to get up in the middle of the night to take it.
Armour vs. Synthroid for Underactive Thyroid:
Q. My thyroid was removed 38 years ago. I did very well on Armour thyroid replacement all of those years. Recently, my endocrinologist insisted that I take Synthroid instead. It made me feel awful.
Finally he put me back on Armour, but kept reducing the dosage. He insisted that the blood work showed that I was getting too much.
I reached a point where I was so fatigued that I could do nothing. When I saw another specialist, she said that my thyroid dosage was too low. In three weeks on the higher dose she prescribed, I have begun to feel better. Quality of life is important!
Which Thyroid Medicine Will Work for You?
A. For many people, levothyroxine (Levoxyl, Synthroid, Tirosint, Unithroid) is an effective treatment to replace missing thyroid hormone. However, up to 15 percent of those with an underactive thyroid may have a genetic variation that makes them less efficient at converting levothyroxine (T4) to the active form, triiodothyronine (T3).
Many of these individuals feel better taking a desiccated thyroid preparation such as Armour, Nature-Throid or Westhroid. This is not appropriate for everyone, as these products are derived from pig thyroid gland. As a result, they are not desirable for vegetarians or people following Muslim or Jewish dietary laws. Doctors may worry that these natural products are more variable in dose than synthetic levothyroxine, though we have not seen head-to-head studies confirming this problem.
Helen reported:
“It is very difficult to find an allopathic physician who is willing to prescribe anything but synthroid and its generics. I have one; however, any endo I have seen wants me to drop the Naturethroid and go back to a synthetic. While I have not experienced any of the wonders others have by switching, I am not interested in switching once again. As I have had thyroid cancer, it is important to my health to take enough to suppress my TSH score. Except now that I am 78, two endos have told me I no longer need concern myself about this. The same endos who said tight control of diabetes is no longer necessary. Well, I could live to 105 and be sorry I did not take care of these things when I could; so I didn’t listen. One of the endos was at Stanford, so they are just as rigid in standard of care there as anywhere in the boonies.”
Rebecca wrote:
“Hashimoto’s Thyroiditis has been a nemesis of mine for almost 30 years. That being said, I’ve been on a narrowly varying dose of levothyroxine (between 150 and 175 mcg daily) during that time.
“However: *three* friends of mine (none of whom know each other, or live in the same city) had terrible effects from Armour thyroid. One, a nurse, had cardiac arrhythmia from pills well in excess of the dosage they were supposed to have, sending her to the emergency room. One had a 30 lb. weight gain and brain fog, which resolved quickly after Armour was replaced with generic levothyroxine. The other had neurological problems and tremors, again, resolving after Armour was removed from the equation and replaced with synthetic hormone.
“I have no love for levothyroxine. My friends know me as an earth mother type. But alas, sometimes “natural” isn’t always better.”
Marla said:
“I have suffered with hypothyroid for years. Started with Synthroid with no noticeable results. Switched to Armour thyroid which worked great until my insurance company removed it from their formulary. My doctor had to petition to get my prescription covered again and switch me to Nature-thyroid which has been a miracle drug.
“I STRONGLY recommend that anyone with thyroid issues (and any doctors treating people with thyroid issues) read Root Cause by Izabella Wentz, which my doctor recommended to me.”
Learn More:
We agree that quality of life is an important consideration. You can learn much more about levothyroxine, treatment with T3, desiccated thyroid and getting the best treatment for your thyroid condition in our Guide to Thyroid Hormones. You may also wish to listen to our interview with Mary Shomon and Dr. Antonio Bianco. It is Show 1096: What You Need to Know About Treating Thyroid Disease.
