Thyroid hormone replacement
Is Levothyroxine vegetarian or vegan-friendly?
Vegetarian and vegan patients sometimes ask whether their medication contains animal-derived ingredients. The active substance Levothyroxine in Levothyroxine is almost always synthetically produced; the question typically concerns excipients in the tablet or capsule shell at 25mcg, 50mcg, 75mcg, 100mcg, 150mcg.
Animal-derived excipients in Levothyroxine
Common animal-derived excipients in pharmaceuticals include gelatin (in capsule shells, derived from porcine or bovine sources), lactose (dairy-derived), and certain magnesium stearate sources. The prescribing information and patient leaflet for Levothyroxine list excipients; whether they are animal-derived is sometimes specified, sometimes left ambiguous. Levothyroxine replaces deficient endogenous thyroxine, which is converted in tissues to the active hormone triiodothyronine (T3) by deiodinase enzymes.
Practical guidance
According to general pharmacy practice, vegetarians and vegans concerned about Levothyroxine excipients should ask the pharmacist or manufacturer directly. Many medications have authorised generic versions with different excipient profiles — switching to a generic of Levothyroxine with vegetable-derived excipients is sometimes possible at 25mcg, 50mcg, 75mcg, 100mcg, 150mcg. For strict requirements (e.g. religious or strong ethical), specialist pharmacy consultation gives definitive answers.
Frequently asked questions
Does Levothyroxine contain gelatin? ▾
Whether Levothyroxine contains gelatin depends on the formulation — capsule shells often do, tablet coatings sometimes do. The patient leaflet for Levothyroxine at 25mcg, 50mcg, 75mcg, 100mcg, 150mcg lists excipients; the manufacturer or pharmacist can confirm gelatin source if not explicitly stated.
Is Levothyroxine suitable for vegans? ▾
Most modern tablet formulations are vegan-compatible (active ingredient synthetic, excipients usually plant or mineral), but capsule shells and some coatings may use animal-derived components. For strict vegan requirements, confirm with the manufacturer or pharmacist for the specific Levothyroxine product.
Products containing Levothyroxine
More on Levothyroxine
- With alcoholLevothyroxine and alcohol — is it safe to drink?
- With foodShould Levothyroxine be taken with food?
- Side effectsLevothyroxine side effects: common, rare and warning signs
- Dosage guideLevothyroxine dosage guide: how much to take and when
- OnsetHow fast does Levothyroxine start working?
- DurationHow long does Levothyroxine last?
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.