LEVOXYL® Description

(levothyroxine sodium)

11 DESCRIPTION

LEVOXYL contains the active ingredient, levothyroxine, asynthetic crystalline levothyroxine (T4) in sodium salt form. It is chemically designated as L-3,3',5,5'-tetraiodothyronine monosodium hydrate. Synthetic T4 is identical in chemical structure to the T4 produced in the human thyroid gland. Levothyroxine sodium has an empirical formula of C15H10I4N NaO4 ∙ H2O, molecular weight of 798.85 g/mol (anhydrous), and structural formula as shown:

Chemical Structure

LEVOXYL tablets for oral administration are supplied in the following strengths: 25 mcg, 50 mcg, 75 mcg, 88 mcg, 100 mcg, 112 mcg, 125 mcg, 137 mcg, 150 mcg, 175 mcg, and 200 mcg.

Inactive Ingredients

Calcium sulfate dihydrate, croscarmellose sodium, magnesium stearate, microcrystalline cellulose, and sodium bicarbonate. The following are the coloring additives per tablet strength:

Strength
(mcg)
Color additive(s)
25FD&C Yellow No. 6 Aluminum Lake
50None
75FD&C Blue No. 1 Aluminum Lake, D&C Red No. 30 Aluminum Lake
88FD&C Yellow No. 6 Aluminum Lake, FD&C Blue No. 1 Aluminum Lake, D&C Yellow No. 10 Aluminum Lake
100FD&C Yellow No. 6 Aluminum Lake, D&C Yellow No. 10 Aluminum Lake
112FD&C Yellow No. 6 Aluminum Lake, FD&C Red No. 40 Aluminum Lake, D&C Red No. 30 Aluminum Lake
125FD&C Red No. 40 Aluminum Lake, D&C Yellow No. 10 Aluminum Lake
137FD&C Blue No. 1 Aluminum Lake
150FD&C Blue No. 1 Aluminum Lake, D&C Red No. 30 Aluminum Lake
175FD&C Blue No. 1 Aluminum Lake, D&C Yellow No. 10 Aluminum Lake
200D&C Red No. 30 Aluminum Lake, D&C Yellow No. 10 Aluminum Lake

Find LEVOXYL® medical information:

Find LEVOXYL® medical information:

Our scientific content is evidence-based, scientifically balanced and non-promotional. It undergoes rigorous internal medical review and is updated regularly to reflect new information.

LEVOXYL® Quick Finder

Prescribing Information
Download Prescribing Information

Health Professional Information

Description

11 DESCRIPTION

LEVOXYL contains the active ingredient, levothyroxine, asynthetic crystalline levothyroxine (T4) in sodium salt form. It is chemically designated as L-3,3',5,5'-tetraiodothyronine monosodium hydrate. Synthetic T4 is identical in chemical structure to the T4 produced in the human thyroid gland. Levothyroxine sodium has an empirical formula of C15H10I4N NaO4 ∙ H2O, molecular weight of 798.85 g/mol (anhydrous), and structural formula as shown:

Chemical Structure

LEVOXYL tablets for oral administration are supplied in the following strengths: 25 mcg, 50 mcg, 75 mcg, 88 mcg, 100 mcg, 112 mcg, 125 mcg, 137 mcg, 150 mcg, 175 mcg, and 200 mcg.

Inactive Ingredients

Calcium sulfate dihydrate, croscarmellose sodium, magnesium stearate, microcrystalline cellulose, and sodium bicarbonate. The following are the coloring additives per tablet strength:

Strength
(mcg)
Color additive(s)
25FD&C Yellow No. 6 Aluminum Lake
50None
75FD&C Blue No. 1 Aluminum Lake, D&C Red No. 30 Aluminum Lake
88FD&C Yellow No. 6 Aluminum Lake, FD&C Blue No. 1 Aluminum Lake, D&C Yellow No. 10 Aluminum Lake
100FD&C Yellow No. 6 Aluminum Lake, D&C Yellow No. 10 Aluminum Lake
112FD&C Yellow No. 6 Aluminum Lake, FD&C Red No. 40 Aluminum Lake, D&C Red No. 30 Aluminum Lake
125FD&C Red No. 40 Aluminum Lake, D&C Yellow No. 10 Aluminum Lake
137FD&C Blue No. 1 Aluminum Lake
150FD&C Blue No. 1 Aluminum Lake, D&C Red No. 30 Aluminum Lake
175FD&C Blue No. 1 Aluminum Lake, D&C Yellow No. 10 Aluminum Lake
200D&C Red No. 30 Aluminum Lake, D&C Yellow No. 10 Aluminum Lake
Medication Guide

Health Professional Information

{{section_name_patient}}

{{section_body_html_patient}}

Resources

Didn’t find what you were looking for? Contact us.

MI Digital Assistant

Chat online with Pfizer Medical Information regarding your inquiry on a Pfizer medicine.

Call 800-438-1985*

*Contact Medical Information. 8AM-9PM ET Monday to Friday; excluding holidays.

Medical Inquiry

Submit a medical question for Pfizer prescription products.

Report Adverse Event

Pfizer Safety

To report an adverse event related to the Pfizer-BioNTech COVID-19 Vaccine, and you are not part of a clinical trial* for this product, click the link below to submit your information:

Pfizer Safety Reporting Site

*If you are involved in a clinical trial for this product, adverse events should be reported to your coordinating study site.

If you cannot use the above website, or would like to report an adverse event related to a different Pfizer product, please call Pfizer Safety at (800) 438-1985.

FDA Medwatch

You may also contact the U.S. Food and Drug Administration (FDA) directly to report adverse events or product quality concerns either online at www.fda.gov/medwatch or call (800) 822-7967.