Before reading another word - look at the funding!
The paper defies logic - they claim the maximum dose of aluminium from a tablet is 137 micrograms - which is way below the FDA-determined minimal risk level. Which in itself might provide some reassurance. It totally ignores the possibility of the patient taking two or more tablets! It also ignores that this 137n micrograms is IN ADDITION to any other sources of aluminium.
In the end, my main reason for posting is to highlight that AbbVie felt there was reason to do this research and publish the summary of results. Looks to me as if they are reacting to patients who are questioning both gluten and aluminium content of Synthroid. (Would have been far more useful if they had done the research across the market, even if just the USA market. Not just their own. Perhaps they found every other make had less aluminium and so didn't publish those results!)
Adv Ther. 2017 Jun 26. doi: 10.1007/s12325-017-0575-y. [Epub ahead of print]
Gluten and Aluminum Content in Synthroid® (Levothyroxine Sodium Tablets).
Espaillat R1, Jarvis MF2, Torkelson C2, Sinclair B2.
1 AbbVie Inc., North Chicago, IL, USA. firstname.lastname@example.org.
2 AbbVie Inc., North Chicago, IL, USA.
Inquiries from healthcare providers and patients about the gluten and aluminum content of Synthroid® (levothyroxine sodium tablets) have increased. The objective of this study was to measure and evaluate the gluten content of the raw materials used in the manufacturing of Synthroid. Additionally, this study determined the aluminum content in different strengths of Synthroid tablets by estimating the amount of aluminum in the raw materials used in the manufacturing of Synthroid.
Gluten levels of three lots of the active pharmaceutical ingredient (API) and one lot of each excipient from different vendors were examined. The ingredients in all current Synthroid formulations (strengths) were evaluated for their quantity of aluminum.
Gluten concentrations were below the lowest limit of detection (<3.0 ppm) for all tested lots of the API and excipients of Synthroid tablets. Aluminum content varied across tablet strengths (range 19-137 µg/tablet). Gluten levels of the API and excipients were found to be below the lowest level of detection and are considered gluten-free based on the US Food and Drug Administration (FDA) definition for food products. Across the various tablet strengths of Synthroid, the maximum aluminum levels were well below the FDA-determined minimal risk level for chronic oral aluminum exposure (1 mg/kg/day).
These data demonstrate that Synthroid tablets are not a source for dietary gluten and are a minimal source of aluminum.
Aluminum; Chemical analysis; Endocrinology; Excipients; Gluten; Hypothyroidism; Levothyroxine; Synthroid