Drug & supplement interaction

Lactoferrin + Naproxen

Naproxen brand names: Naprosyn, Naprelan, Anaprox, Anaprox DS, Naproxyn, and others.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 13, 2026
The bottom line No known interaction

We found no known interaction between Lactoferrin and Naproxen 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 two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

Lactoferrin and Naproxen

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 Naproxen and Lactoferrin 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 Lactoferrin at all — not against Naproxen, 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.

Lactoferrin safety at a glance

Lactoferrin overall Use caution Generally well tolerated short-term, but high-quality long-term safety data are limited.
Pregnancy Likely Safe When used orally in amounts commonly found in foods. Lactoferrin has Generally Regarded as Safe (GRAS) status in the US. Read the full pregnancy detail
Breastfeeding Likely Safe When used orally in amounts commonly found in foods. Lactoferrin has Generally Regarded as Safe (GRAS) status in the US. There is insufficient reliable informat... Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Naproxen and Lactoferrin? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

No Interaction Found — But Data Suggests Lactoferrin and Naproxen May Share Several of the Same Side Effects

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do. One of them is worth acting on rather than waiting out — marked below.

  • Yellowing of the skin or eyes Worth acting on Additional detail

    Lactoferrin

    “Orally, lactoferrin has been reported to cause diarrhea in some patients. At higher doses of 7.2 grams daily, anorexia and constipation have been reported. However, gastrointestinal effects of lactoferrin, including epigastric pain, constipation, nausea, and diarrhea, are less common than with other sources of iron such as ferrous sulfate.”

    Lactoferrin · Natural Medicines adverse-effect record, reported in anorexia.

    4 sources cited
    1. 13323. Okada S, Tanaka K, Sato T, et al. Dose-response trial of lactoferrin in patients with chronic hepatitis C. Jpn J Cancer Res 2002;93:1063-9. PubMed
    2. 97788. Abu Hashim H, Foda O, Ghayaty E. Lactoferrin or ferrous salts for iron deficiency anemia in pregnancy: A meta-analysis of randomized trials. Eur J Obstet Gynecol Reprod Biol. 2017;219:45-52. PubMed
    3. 104857. Tarnow-Mordi WO, Abdel-Latif ME, Martin A, et al. The effect of lactoferrin supplementation on death or major morbidity in very low birthweight infants (LIFT): a multicentre, double-blind, randomised controlled trial. Lancet Child Adolesc Health. 2020 Jun PubMed
    4. 104858. ELFIN trial investigators group. Enteral lactoferrin supplementation for very preterm infants: a randomised placebo-controlled trial. Lancet. 2019 Feb 2;393(10170):423-433. doi: 10.1016/S0140-6736(18)32221-9.

    Naproxen

    Listed in the ADVERSE REACTIONS section of the FDA label for Naproxen. Read the label on DailyMed ›

  • Chills / Tiredness reported in 7.9% of FDA reports for Naproxen Additional detail

    Lactoferrin

    “Orally, at higher doses of 7.2 grams daily, lactoferrin has been reported to cause fatigue and chills.”

    Lactoferrin · Natural Medicines adverse-effect record, reported in fatigue.

    1 source cited
    1. 13323. Okada S, Tanaka K, Sato T, et al. Dose-response trial of lactoferrin in patients with chronic hepatitis C. Jpn J Cancer Res 2002;93:1063-9. PubMed

    Naproxen

    Listed in the ADVERSE REACTIONS section of the FDA label for Naproxen, and in voluntary FDA adverse-event reports. Read the label on DailyMed ›

  • Reduced appetite Additional detail

    Lactoferrin

    Recorded for Lactoferrin in the same Natural Medicines adverse-effect record shown under Yellowing of the skin or eyes above.

    Naproxen

    Listed in the ADVERSE REACTIONS section of the FDA label for Naproxen. Read the label on DailyMed ›

  • Constipation / Diarrhea / Nausea reported in 7.4% of FDA reports for Naproxen Additional detail

    Lactoferrin

    “Orally, bovine and human recombinant lactoferrin are well tolerated when used in typical doses. However, hjgher doses of 7.2 grams daily increase the risk of side effects and decrease tolerability.

    Topically, there is a limited amount of information on the adverse effects of lactoferrin.

    Intravaginally, no adverse effects have been reported.”

    Lactoferrin · Natural Medicines adverse-effect record, reported in constipation.

    Naproxen

    Listed in the ADVERSE REACTIONS section of the FDA label for Naproxen, and in voluntary FDA adverse-event reports. Read the label on DailyMed ›

Reported for Lactoferrin but not commonly for Naproxen: a bowel blockage.

Effects for Naproxen come from the ADVERSE REACTIONS section of its FDA label; effects for Lactoferrin come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 165,062 voluntary FDA FAERS reports for Naproxen that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Special populations

Lactoferrin in Pregnancy & Breastfeeding

Pregnancy Likely Safe

When used orally in amounts commonly found in foods. Lactoferrin has Generally Regarded as Safe (GRAS) status in the US.

Pregnancy Possibly Safe

When used orally in medicinal amounts. Lactoferrin has been used with apparent safety during the second or third trimester of pregnancy at doses of up to 250 mg daily for up to 8 weeks. Also, bovine lactoferrin has been used with apparent safety throughout all trimesters of pregnancy at doses of up to 200 mg daily. There is insufficient reliable information available about the safety of intravaginal lactoferrin during pregnancy and lactation; avoid using.

Lactation Likely Safe

When used orally in amounts commonly found in foods. Lactoferrin has Generally Regarded as Safe (GRAS) status in the US. There is insufficient reliable information available about the safety of lactoferrin when used medicinally during lactation; avoid using.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

From our Q&A

Questions About Lactoferrin or Naproxen

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Lactoferrin or Naproxen, 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 Naproxen

This page covers Lactoferrin only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Naproxen page lists 311 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Asarabacca (major), Beer (major), Danshen (major) and Piracetam (major).

By severity: 7 major · 260 moderate · 44 minor.

Open the Naproxen interaction page

One more smart check

Taking Lactoferrin as Part of a Dietary Supplement Product? Check It for Interactions

We hold 292 real supplement products containing Lactoferrin, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Lactoferrin. Even though Lactoferrin itself has no known interaction with Naproxen, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Lactoferrin and Naproxen 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 Lactoferrin
Top half

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

29 days ago today
Medication Naproxen
Top 5%

#57 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 Lactoferrin reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Lactoferrin and Naproxen records this page draws on were last updated July 11, 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 .
Supplement

About Lactoferrin

What is Lactoferrin?

  • Iron deficiency and anemia support
  • Immune support
  • Gut health
  • Stomach (H. pylori) infection
  • Acne
  • Diarrhea prevention in infants

Lactoferrin is an iron-binding protein found naturally in milk and other body fluids, and supplements are usually made from cow's milk or rice. It is being studied for immune support, iron levels, gut health, and infections, but the evidence is still limited and mixed for most uses. It is generally well tolerated, but talk with a pharmacist or doctor before starting it.

Protein from milk (colostrum), or made with recombinant technology · Capsules, tablets, powders; also added to some infant formulas and functional foods

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

Lactoferrin: dosing

There is no official standardized dose of lactoferrin, and the right amount can depend on the product, the form, and the reason for use. Doses used in research have varied widely.The best approach is to follow the directions on the product label and not exceed the recommended amount.

From our Lactoferrin monograph — the full record covers uses, side effects and every documented interaction.

Read the full Lactoferrin monograph & all interactions
Medication

About Naproxen

What Is Naproxen Used For?

Brand names: Naprosyn, Naprelan, Anaprox, Anaprox DS, Naproxyn, Navalbine, Naproxen, Naprosyn EC, Napro-Na, Aleve, Arthroxen, Synflex, EC-Naprosyn

Naproxen tablets, naproxen sodium tablets, and naproxen oral suspension are used to relieve the signs and symptoms of rheumatoid arthritis, osteoarthritis, ankylosing spondylitis, and polyarticular juvenile idiopathic arthritis. They are also used for tendonitis, bursitis, and acute gout, and for managing pain and primary dysmenorrhea (menstrual cramps).

Naproxen Sodium Controlled-Release Tablets are indicated for the same conditions plus the relief of mild to moderate pain. Several over-the-counter naproxen sodium products are indicated for the temporary relief of minor aches and pains from headache, backache, muscular aches, toothache, menstrual cramps, minor arthritis pain, and the common cold, and to temporarily reduce fever.

Most-Reported Side Effects for Naproxen

From FAERS, the FDA’s public side-effect reporting system (165,062 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Fatigue 13,047 reports
Nausea 12,185 reports
Arthralgia 11,086 reports
Headache 10,504 reports
Diarrhea 9,841 reports
See full Naproxen drug information
Keep checking

Other Drugs & Lactoferrin

Browse every other medication we’ve checked against Lactoferrin — 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 Lactoferrin 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 Lactoferrin list.

See the full Lactoferrin interactions page
See every supplement checked against Naproxen, ranked by severity
Evidence & sources

Lactoferrin References

The 6 references that drive our Lactoferrin 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.

  1. Food and Drug Administration, CFSAN/Office of Food Additive Safety. Agency Response Letter GRAS Notice No. GRN 000130. 2003. Available at: http://www.cfsan.fda.gov/~rdb/opa-g130.html (Accessed 29 June 2005).
  2. Okada S, Tanaka K, Sato T, et al. Dose-response trial of lactoferrin in patients with chronic hepatitis C. Jpn J Cancer Res 2002;93:1063-9. PubMed
  3. Abu Hashim H, Foda O, Ghayaty E. Lactoferrin or ferrous salts for iron deficiency anemia in pregnancy: A meta-analysis of randomized trials. Eur J Obstet Gynecol Reprod Biol. 2017;219:45-52. PubMed
  4. Tarnow-Mordi WO, Abdel-Latif ME, Martin A, et al. The effect of lactoferrin supplementation on death or major morbidity in very low birthweight infants (LIFT): a multicentre, double-blind, randomised controlled trial. Lancet Child Adolesc Health. 2020 Jun PubMed
  5. ELFIN trial investigators group. Enteral lactoferrin supplementation for very preterm infants: a randomised placebo-controlled trial. Lancet. 2019 Feb 2;393(10170):423-433. doi: 10.1016/S0140-6736(18)32221-9.
  6. Lepanto MS, Rosa L, Cutone A, Conte MP, Paesano R, Valenti P. Efficacy of lactoferrin oral administration in the treatment of anemia and anemia of inflammation in pregnant and non-pregnant women: An interventional study. Front Immunol. 2018 Sep 21;9:2123. 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 Lactoferrin and Naproxen Together: Common Questions

Is it safe to take Lactoferrin with Naproxen?
We do not list a known interaction between Lactoferrin and Naproxen. 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.
Do Lactoferrin and Naproxen have any of the same side effects?
Yes — our sources link each of them separately to 7 of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
Does Naproxen interact with any supplements?
Yes. Naproxen has documented interactions with 311 supplements in our database — Lactoferrin is not one of them. The Naproxen 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

Lactoferrin monograph Uses, safety profile, and every drug interaction in one place Naproxen drug information The full plain-English guide to this medication Naproxen supplement interactions Every supplement checked against Naproxen, 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 6 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Naproxen and Lactoferrin?

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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.