Drug & supplement interaction

Lorenzo's Oil + Levothyroxine

Levothyroxine brand names: Euthyrox, Levothroid, Unithroid, Synthroid, Levoxyl, and others.

No Known Interaction

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated July 2026 · Pair last verified Sep 13, 2026

The bottom line No known interaction

We found no known interaction between Lorenzo's Oil and Levothyroxine in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the label for Levothyroxine states a food rule worth keeping to.

Know someone taking this? Share

Facebook Post Reddit Email

On this page

Interaction report

Lorenzo's Oil and Levothyroxine

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Levothyroxine and Lorenzo's Oil in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

Worth understanding: our licensed dataset holds no drug-interaction record for Lorenzo's Oil at all — not against Levothyroxine, and not against any other medication we track. This verdict therefore rests on the absence of any recorded data, not on research that looked at this combination and found nothing. We cannot rule an interaction out.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Lorenzo's Oil safety at a glance

Lorenzo's Oil overall Use caution It is a medical treatment for a rare disease and should only be used under specialist supervision, not as a general supplement.

Pregnancy Avoid Safety in pregnancy is not established; use only if a specialist directs it.

Breastfeeding Avoid Safety while breastfeeding is not established; talk to your doctor first.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Levothyroxine and Lorenzo's Oil? Ask Dr. Brian Staiger, PharmD, BCPS directly ›

What to actually watch for

What Lorenzo's Oil Itself Has Been Linked To

This is not an interaction — nothing below involves Levothyroxine. It is the side-effect record for Lorenzo's Oil on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Lorenzo's Oil, this list is the first place to look. 2 entries are worth acting on rather than waiting out — marked below.

A low platelet count / A low white blood cell count / Bleeding or bruising Worth acting on Additional detail
“Orally, Lorenzo's oil can cause thrombocytopenia, neutropenia, purpura, petechiae, and bleeding (6,924,926,927).”

Lorenzo's Oil · Natural Medicines adverse-effect record, reported in thrombocytopenia.
4 sources cited

6. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.

924. Aubourg P, Adamsbaum C, Lavallard-Rousseau MC, et al. A two-year trial of oleic and erucic acids (Lorenzo's oil) as treatment for adrenomyeloneuropathy. N Engl J Med 1993;329:745-52. PubMed

926. Chai BC, Etches WS, Stewart MW, Siminoski K. Bleeding in a patient taking Lorenzo's oil: evidence for a vascular defect. Postgrad Med J 1996;72:113-4.

927. Revell P, Green A, Green S. Platelets in treated adrenoleukodystrophy: a brief report. J Inherit Metab Dis 1995;18:635-7. PubMed
“Orally, Lorenzo's oil can cause thrombocytopenia, purpura, petechiae, bleeding, and neutropenia (6,924,926,927).”

Lorenzo's Oil · Natural Medicines adverse-effect record, reported in thrombocytopenia.
4 sources cited

6. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.

924. Aubourg P, Adamsbaum C, Lavallard-Rousseau MC, et al. A two-year trial of oleic and erucic acids (Lorenzo's oil) as treatment for adrenomyeloneuropathy. N Engl J Med 1993;329:745-52. PubMed

926. Chai BC, Etches WS, Stewart MW, Siminoski K. Bleeding in a patient taking Lorenzo's oil: evidence for a vascular defect. Postgrad Med J 1996;72:113-4.

927. Revell P, Green A, Green S. Platelets in treated adrenoleukodystrophy: a brief report. J Inherit Metab Dis 1995;18:635-7. PubMed
A higher chance of infection Worth acting on Additional detail
“In one case report, a 39-year-old man with adrenoleukodystrophy developed lipoid pneumonia while taking Lorenzo's oil. He presented with respiratory failure; bronchoalveolar lavage produced fluid with an oily appearance.”

Lorenzo's Oil · Natural Medicines adverse-effect record, reported in adrenoleukodystrophy (ald).
1 source cited

99422. Majori M, Scarascia A, Anghinolfi M, et al. Lipoid pneumonia as a complication of Lorenzo's oil therapy in a patient with adrenoleukodystrophy. J Bronchology Interv Pulmonol 2014;21(3):271-3. doi: 10.1097/LBR.0000000000000084. PubMed

Everything above comes from the Natural Medicines adverse-effect record for Lorenzo's Oil — expand a row for the licensed statement it rests on. We read the ADVERSE REACTIONS section of Levothyroxine’s FDA label too, and the two lists don’t meaningfully overlap — which is why no Levothyroxine column appears here.

How to take them

Some Levothyroxine Products Have a Food Rule — Lorenzo's Oil Should Not Break It

At least one FDA label for a product containing Levothyroxine says to take it on an empty stomach. Most supplements — Lorenzo's Oil included — are taken with a meal, so the easy mistake is swallowing both together at breakfast. Where that rule applies, keep Levothyroxine on its own and move Lorenzo's Oil to a meal later in the day.

This may not be true of your version. Food instructions belong to the product, not the ingredient: two Levothyroxine products can carry different directions, and extended-release forms often differ from immediate-release ones. The label we read is quoted below — check the directions on your own box or bottle, or ask your pharmacist, for how to take the exact product you were given.

A food rule is not an interaction — it is about how much of the medicine you absorb. The directions that came with your own product, and your pharmacist, outrank anything on this page.

From our Q&A

Questions About Lorenzo's Oil or Levothyroxine

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Lorenzo's Oil or Levothyroxine, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Levothyroxine

This page covers Lorenzo's Oil only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Levothyroxine page lists 50 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Tiratricol (major), Acetyl-l-carnitine (moderate), Alpha-lipoic Acid (moderate) and Ascophyllum Nodosum (moderate).

By severity: 2 major · 39 moderate · 9 minor.

From our pharmacist’s overview on the Levothyroxine page

“Levothyroxine replaces a hormone your body measures in tiny amounts, so small shifts in its blood level show up in how you feel, and I treat this list with genuine care. Nearly everything on it does one of two things: blocks the pill from being absorbed in the gut, the way everyday minerals like calcium do by binding it into complexes,…”

Reviewed by 2 · Jul 18, 2026

Open the Levothyroxine interaction page

How much people look this up

Where Lorenzo's Oil and Levothyroxine Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Lorenzo's Oil

Steady interest

#1,042 of 1,452 supplements looked up here in the last 7 days

29 days ago today

Medication Levothyroxine

Top 10

#2 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Where does our data come from?

Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Lorenzo's Oil reference on this page ↓
Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Lorenzo's Oil and Levothyroxine records this page draws on were last updated July 10, 2026.
What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.

Data structure & sourcing designed and verified by Dr. Brian Staiger, PharmD, BCPS.

Supplement

About Lorenzo's Oil

What is Lorenzo's Oil?

Adrenoleukodystrophy (ALD)
Adrenomyeloneuropathy (AMN)
Lowering very long-chain fatty acids in blood
Slowing progression of certain inherited disorders

Lorenzo's Oil is not a typical herbal supplement—it is a specially formulated mixture of two fatty acids (glyceryl trioleate and glyceryl trierucate, in a 4:1 ratio) developed to lower very long-chain fatty acids in people with adrenoleukodystrophy (ALD). It can normalize blood fatty acid levels and may help delay disease in some boys who are not yet showing symptoms, but it is not a cure and should only be used under specialist medical supervision.

Refined plant-derived oils (rapeseed/olive oil sources) · Oral liquid oil (prescription-style medical formulation)

An interaction check asks whether these two react with each other — it does not ask whether Lorenzo's Oil is a good idea for someone in your situation. Here is what our Lorenzo's Oil record says about it on its own.

Lorenzo's Oil: dosing

There is no standard over-the-counter dose for Lorenzo's Oil. When used medically, the amount is calculated by a specialist based on the person's body and is adjusted using blood tests and a carefully controlled low-fat diet.Because dosing must be individualized and monitored, you should not try to dose this product yourself. Do not use it as a casual supplement.

From our Lorenzo's Oil monograph — the full record covers uses, side effects and every documented interaction.

Read the full Lorenzo's Oil monograph & all interactions

Medication

About Levothyroxine

What Is Levothyroxine Used For?

Brand names: Euthyrox, Levothroid, Unithroid, Synthroid, Levoxyl, Levo-T, Eltroxin, Estre, Levothyroxine, Novothyrox, Levolet

Levothyroxine replaces or supplements the thyroid hormone your body isn't making enough of. It's used for hypothyroidism — an underactive thyroid — in adults, children, and even newborns, whether the cause is the thyroid gland itself, the pituitary gland, or the hypothalamus in the brain.

It's also used alongside surgery and radioiodine treatment in people with certain types of thyroid cancer, to help suppress the hormone that can stimulate cancer growth. It is not meant for weight loss, treating benign thyroid nodules in people who have enough iodine, or for hypothyroidism during recovery from a temporary condition called subacute thyroiditis.

See full Levothyroxine drug information

Keep checking

Other Drugs & Lorenzo's Oil

Browse every other medication we’ve checked against Lorenzo's Oil — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major

0Moderate

0Minor

2,829No known interaction

2,829 No interaction

No interaction 2,829 drugs checked — show the list

We also checked Lorenzo's Oil against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,829 medications checked with no known interaction — see the full Lorenzo's Oil list.

See the full Lorenzo's Oil interactions page

See every supplement checked against Levothyroxine, ranked by severity

Evidence & sources

Lorenzo's Oil References

The 12 references that drive our Lorenzo's Oil monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
Kaplan PW, Tusa RJ, Shankroff J, et al. Visual evoked potentials in adrenoleukodystrophy: a trial with glycerol trioleate and Lorenzo oil. Ann Neurol 1993;34:169-74.
Poulos A, Gibson R, Sharp P, et al. Very long chain fatty acids in X-linked adrenoleukodystrophy brain after treatment with Lorenzo's oil. Ann Neurol 1994;36:741-6. PubMed
Duchesne N, Dufour M, Bouchard G, et al. Adrenoleukodystrophy: magnetic resonance follow-up after Lorenzo's oil therapy. Can Assoc Radiol J 1995;46:386-91.
Moser HW. Clinical and therapeutic aspects of adrenoleukodystrophy and adrenomyeloneuropathy. J Neuropathol Exp Neurol 1995;54:740-5. PubMed
Aubourg P, Adamsbaum C, Lavallard-Rousseau MC, et al. A two-year trial of oleic and erucic acids (Lorenzo's oil) as treatment for adrenomyeloneuropathy. N Engl J Med 1993;329:745-52. PubMed
Chai BC, Etches WS, Stewart MW, Siminoski K. Bleeding in a patient taking Lorenzo's oil: evidence for a vascular defect. Postgrad Med J 1996;72:113-4.
Revell P, Green A, Green S. Platelets in treated adrenoleukodystrophy: a brief report. J Inherit Metab Dis 1995;18:635-7. PubMed
Maeda K, Suzuki Y, Yajima S, et al. Improvement of clinical and MRI findings in a boy with adrenoleukodystrophy by dietary erucic acid therapy. Brain Dev 1992;14:409-12.
Wong V. Adrenoleukodystrophy in a Chinese boy. Brain Dev 1992;14:276-7. PubMed
Moser HW, Raymond GV, Lu SE, et al. Follow-up of 89 asymptomatic patients with adrenoleukodystrophy treated with Lorenzo's Oil. Arch Neurol 2005;62:1073-80. PubMed
Majori M, Scarascia A, Anghinolfi M, et al. Lipoid pneumonia as a complication of Lorenzo's oil therapy in a patient with adrenoleukodystrophy. J Bronchology Interv Pulmonol 2014;21(3):271-3. doi: 10.1097/LBR.0000000000000084. PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Lorenzo's Oil and Levothyroxine Together: Common Questions

Is it safe to take Lorenzo's Oil with Levothyroxine?

We do not list a known interaction between Lorenzo's Oil and Levothyroxine. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.

Should I take Lorenzo's Oil and Levothyroxine at the same time of day?

At least one FDA label for a product containing Levothyroxine says to take it on an empty stomach, and supplements are usually taken with a meal — so taking them together at breakfast is the easy mistake. Where that applies, keep Levothyroxine on its own and move Lorenzo's Oil to a meal later in the day. Food instructions belong to the product rather than the ingredient, so check the directions on your own box. This is about absorption, not an interaction.

Does Levothyroxine interact with any supplements?

Yes. Levothyroxine has documented interactions with 50 supplements in our database — Lorenzo's Oil is not one of them. The Levothyroxine interaction page linked on this page lists every one, ranked by severity.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Where next

Keep Exploring

Lorenzo's Oil monograph Uses, safety profile, and every drug interaction in one place Levothyroxine drug information The full plain-English guide to this medication Levothyroxine supplement interactions Every supplement checked against Levothyroxine, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 12 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Levothyroxine and Lorenzo's Oil?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.