MIKEK asked
I am on Synthroid and Nexium. Is there any issue with taking Benefiber? I read that Synthroid is affected by fiber, so is Benefiber bad to take when taking Synthroid? How long after I take my Synthroid (in the morning) can I take Benefiber?
At a glance
- Synthroid should not be taken with any fiber product, including Benefiber. Doing so can significantly affect the absorption of Synthroid. They should be separated by at least 4 hours.
Answer
You certainly should take your Synthroid (levothyroxine) and Benefiber (wheat dextrin) at separate times, and not together, to avoid an interaction.
Taking them together could result in decreased absorption of your Synthroid, potentially causing your thyroid levels to drop too low (i.e., hypothyroidism). Symptoms of hypothyroidism include:
- Fatigue
- Weakness
- Shivering
- Decreased metabolism
- Brittle hair nails
If you ever notice any of the above symptoms, be sure to speak with your doctor about your therapy.
How To Take Synthroid
It is important to take Synthroid in a consistent manner, by itself on an empty stomach, most preferably in the morning. Taking it inconsistently, or with food, will make it difficult, if not impossible, to find the correct dose for you as your thyroid levels may fluctuate.
It is important to remember that doses of Synthroid are very low, and are measured in micrograms (1/1000 of a milligram). Even small changes to a dose make a significant impact and taking Synthroid with fiber will likely alter the amount you absorb.
The prescribing information for Synthroid states multiple times how it is best taken for optimal effects:
Administer SYNTHROID as a single daily dose, on an empty stomach, one-half to one hour before breakfast.
Avoid Synthroid With Fiber
The prescribing information also explicitly warns against taking with drugs known to decrease absorption, such as fiber:
