Drug & supplement interaction

Vitamin A + Mepolizumab

Mepolizumab brand name: Nucala.

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 Vitamin A and Mepolizumab 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.

Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Vitamin A and Mepolizumab

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 Mepolizumab and Vitamin A 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.

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.

Vitamin A safety at a glance

Vitamin A overall Use caution Generally safe at recommended amounts, but high doses can be toxic because it builds up in the body.
Pregnancy Likely Safe When used orally or intramuscularly and appropriately. Vitamin A, as pre-formed vitamin A (retinol or retinyl ester), is safe during pregnancy and lactation whe... Read the full pregnancy detail
Breastfeeding Likely Safe When used orally or intramuscularly and appropriately. Vitamin A, as pre-formed vitamin A (retinol or retinyl ester), is safe during pregnancy and lactation whe... 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 Mepolizumab and Vitamin A? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
Keep it in perspective

Vitamin A Does Interact With Other Medications

Vitamin A has 9 major, 378 moderate known drug interactions in our database — Mepolizumab isn’t one of them. If you take anything else, check it against the full list below.

Major 9 Moderate 378 No known interaction 2,443 (incl. Mepolizumab)
Taking anything else?

Check Another of Your Medications Against Vitamin A

Covers the 2,830 medications we’ve checked against Vitamin A. Pick one to open its full report.

What to actually watch for

No Interaction Found — But Data Suggests Vitamin A and Mepolizumab 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.

  • A higher chance of infection Worth acting on reported in 9.4% of FDA reports for Mepolizumab Additional detail

    Vitamin A

    “There is some evidence that oral vitamin A supplementation might increase the risk of pneumonia and diarrhea in children. Although vitamin A can prevent diarrhea and reduce mortality in malnourished children, doses as low as 10,000 IU weekly for 40 weeks have been associated with pneumonia and diarrhea in well-nourished children.”

    Vitamin A · Natural Medicines adverse-effect record, reported in diarrhea.

    2 sources cited
    1. 319. Griffiths JK. The vitamin A paradox. J Pediatr 2000;137:604-7.. PubMed
    2. 82288. Grotto, I., Mimouni, M., Gdalevich, M., and Mimouni, D. Vitamin A supplementation and childhood morbidity from diarrhea and respiratory infections: a meta-analysis. J Pediatr 2003;142(3):297-304. PubMed

    Mepolizumab

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

  • Joint pain Additional detail

    Vitamin A

    “Vitamin A can increase the risk for osteoporosis and fractures. Observational research has found that chronic, high intake of vitamin A 10,000 IU or more per day is associated with an increased risk of osteoporosis and hip fracture in postmenopausal adults, as well as overall risk of fracture in middle-aged males.”

    Vitamin A · Natural Medicines adverse-effect record, reported in bone loss.

    6 sources cited
    1. 7712. Feskanich D, Singh V, Willett WC, Colditz GA. Vitamin A intake and hip fractures among postmenopausal women. JAMA 2002;287:47-54. PubMed
    2. 7713. Melhus H, Michaelsson K, Kindmark A, et al. Excessive dietary intake of vitamin A is associated with reduced bone mineral density and increased risk for hip fracture. Ann Intern Med 1998;129:770-8. PubMed
    3. 9190. Michaelsson K, Lithell H, Vessby B, Melhus H. Serum retinol levels and the risk of fracture. N Engl J Med 2003;348:287-94.. PubMed
    4. 107294. Knapik JJ, Hoedebecke SS. Vitamin A and bone fractures: systematic review and meta-analysis. J Spec Oper Med 2021;21(2):100-7. PubMed
    5. 95051. Baineni R, Gulati R, Delhi CK. Vitamin A toxicity presenting as bone pain. Arch Dis Child. 2017;102(6):556-8. PubMed
    6. 15. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.

    Mepolizumab

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

  • Itching Additional detail

    Vitamin A

    “Chronic oral use of large amounts of vitamin A causes symptoms of vitamin A toxicity including dry skin and lips; cracking, scaling, and itchy skin; skin redness and rash; hyperpigmentation; shiny skin, and massive skin peeling. Hypervitaminosis A can cause brittle nails, cheilitis, gingivitis, and hair loss (15,95051).”

    Vitamin A · Natural Medicines adverse-effect record, reported in alopecia.

    3 sources cited
    1. 7135. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academy Press, 2002.
    2. 95051. Baineni R, Gulati R, Delhi CK. Vitamin A toxicity presenting as bone pain. Arch Dis Child. 2017;102(6):556-8. PubMed
    3. 15. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.

    “Hypervitaminosis A can cause reduced menstrual flow (15). Intravaginally, all-trans retinoic acid can cause vaginal discharge, itching, irritation, and burning.”

    Vitamin A · Natural Medicines adverse-effect record, reported in pruritus.

    2 sources cited
    1. 15. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
    2. 9199. Meyskens FL Jr, Graham V, Chvapil M, et al. A phase I trial of beta-all-trans-retinoic acid delivered via a collagen sponge and a cervical cap for mild or moderate intraepithelial cervical neoplasia. J Natl Cancer Inst 1983;71:921-5..

    Mepolizumab

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

  • Stomach pain Additional detail

    Vitamin A

    “There is some evidence that oral vitamin A supplementation might increase the risk of diarrhea in children. Although vitamin A can prevent diarrhea and reduce mortality in malnourished children, doses as low as 10,000 IU weekly for 40 weeks have been associated with diarrhea in well-nourished children.”

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

    6 sources cited
    1. 319. Griffiths JK. The vitamin A paradox. J Pediatr 2000;137:604-7.. PubMed
    2. 82326. Mahalanabis, D., Lahiri, M., Paul, D., Gupta, S., Gupta, A., Wahed, M. A., and Khaled, M. A. Randomized, double-blind, placebo-controlled clinical trial of the efficacy of treatment with zinc or vitamin A in infants and young children with severe acute l
    3. 82389. Long, K. Z., Montoya, Y., Hertzmark, E., Santos, J. I., and Rosado, J. L. A double-blind, randomized, clinical trial of the effect of vitamin A and zinc supplementation on diarrheal disease and respiratory tract infections in children in Mexico City, Mex
    4. 7135. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academy Press, 2002.
    5. 100329. Masnadi Shirazi K, Nikniaz Z, Masnadi Shirazi A, Rohani M. Vitamin A supplementation decreases disease activity index in patients with ulcerative colitis: A randomized controlled clinical trial. Complement Ther Med. 2018 Dec;41:215-219. PubMed
    6. 95051. Baineni R, Gulati R, Delhi CK. Vitamin A toxicity presenting as bone pain. Arch Dis Child. 2017;102(6):556-8. PubMed

    Mepolizumab

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

  • Tiredness / Headache Additional detail

    Vitamin A

    “Orally, adverse effects from a single large dose of vitamin A are more common in young children than adults (15). Headache, increased cerebrospinal fluid pressure, vertigo, and blurred vision have been reported following an acute oral dose of vitamin A 500,000 IU. In children, approximately 25,000 IU/kg can cause headache, irritability, drowsiness, dizziness, delirium, and coma (15).”

    Vitamin A · Natural Medicines adverse-effect record, reported in acne.

    6 sources cited
    1. 15. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
    2. 7135. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academy Press, 2002.
    3. 90784. Mazumder S, Taneja S, Bhatia K, Yoshida S, Kaur J, Dube B, Toteja GS, Bahl R, Fontaine O, Martines J, Bhandari N; Neovita India Study Group. Efficacy of early neonatal supplementation with vitamin A to reduce mortality in infancy in Haryana, India (Neovit
    4. 95053. Darlow BA, Graham PJ, Rojas-Reyes MX. Vitamin A supplementation to prevent mortality and short- and long-term morbidity in very low birth weight infants. Cochrane Database Syst Rev. 2016;(8):CD000501. PubMed
    5. 95054. Haider BA, Sharma R, Bhutta ZA. Neonatal vitamin A supplementation for the prevention of mortality and morbidity in term neonates in low and middle income countries. Cochrane Database Syst Rev. 2017;2:CD006980. PubMed
    6. 95056. Mohammad YM, Raslan IR, Al-Hussain FA. Idiopathic Intracranial Hypertension Induced by Topical Application of Vitamin A. J Neuroophthalmol. 2016;36(4):412-3. PubMed

    Mepolizumab

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

  • Diarrhea Additional detail

    Vitamin A

    Recorded for Vitamin A in the same Natural Medicines adverse-effect record shown under Stomach pain above.

    Mepolizumab

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

Reported for Vitamin A but not commonly for Mepolizumab: liver problems, stomach upset, sweating and a low platelet count.

Effects for Mepolizumab come from the ADVERSE REACTIONS section of its FDA label; effects for Vitamin A come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 49,399 voluntary FDA FAERS reports for Mepolizumab 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

Vitamin A in Pregnancy & Breastfeeding

Pregnancy And Lactation Likely Safe

When used orally or intramuscularly and appropriately. Vitamin A, as pre-formed vitamin A (retinol or retinyl ester), is safe during pregnancy and lactation when used in doses less than 10,000 IU (3000 mcg) per day in adults 19 years of age and older and 2800 mcg daily in those 14-18 years of age. Vitamin A is available in two different forms: pre-formed vitamin A (retinol or retinyl ester) and provitamin A (carotenoids). The safety concerns associated with high vitamin A intake occur with pre-formed vitamin A only. Some supplements contain vitamin A in both pre-formed and provitamin A forms. For these supplements, the amount of pre-formed vitamin A should be used as the reference amount to determine safety.

Pregnancy And Lactation Possibly Unsafe

When used orally or intramuscularly in excessive doses. Daily intake of greater than 10,000 IU (3000 mcg) can cause fetal malformations. Excessive dietary intake of vitamin A has also been associated with teratogenicity. The first trimester of pregnancy seems to be the critical period for susceptibility to vitamin A-associated birth defects such as craniofacial abnormalities and abnormalities of the central nervous system. Pregnant patients should monitor their intake of pre-formed vitamin A (retinol or retinyl ester). This form of vitamin A is found in several foods including animal products, particularly fish and animal liver, some fortified breakfast cereals, and dietary supplements.

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 Vitamin A or Mepolizumab

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

One more smart check

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

We hold 19,215 real supplement products containing Vitamin A, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Vitamin A. Even though Vitamin A itself has no known interaction with Mepolizumab, 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 Vitamin A and Mepolizumab 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 Vitamin A
Top 1%

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

29 days ago today
Medication Mepolizumab
Steady interest

#1,677 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 Vitamin A reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Vitamin A and Mepolizumab 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 .
Supplement

About Vitamin A

What is Vitamin A?

  • Eye and vision health
  • Skin health and acne
  • Immune support
  • Correcting vitamin A deficiency
  • Childhood growth and development

Vitamin A is an essential nutrient important for vision, skin, immune function, and growth. Most people get enough from a balanced diet, and supplements are mainly useful for correcting a true deficiency. Because vitamin A is fat-soluble and can build up to harmful levels, more is not better, and high doses are especially risky in pregnancy.

Capsules, softgels, tablets, liquid drops, multivitamins; also found in foods

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

Vitamin A: dosing

Vitamin A needs are usually described in micrograms of retinol activity equivalents (mcg RAE) or sometimes older International Units (IU). Because of the risk of buildup, this is one supplement where taking extra is not helpful and can be harmful.There is no single "best" supplement dose for most people, and many do not need a separate vitamin A supplement at all.

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

Read the full Vitamin A monograph & all interactions
Medication

About Mepolizumab Injection

What Is Mepolizumab Injection Used For?

Brand name: Nucala

Nucala is used as an add-on maintenance treatment — meaning it works alongside other medications, not instead of them. It is approved for severe asthma (in patients 6 years and older with high eosinophil levels), chronic rhinosinusitis with nasal polyps (CRSwNP) in adults 18 and older whose symptoms aren't controlled by nasal corticosteroids alone, and COPD in adults with an eosinophilic phenotype whose disease isn't adequately controlled.

Nucala is also approved to treat eosinophilic granulomatosis with polyangiitis (EGPA), a rare form of blood vessel inflammation, and hypereosinophilic syndrome (HES), a condition involving dangerously elevated eosinophil counts, in adults and adolescents 12 and older. It is not meant to relieve sudden asthma attacks or acute COPD flares.

Most-Reported Side Effects for Mepolizumab

From FAERS, the FDA’s public side-effect reporting system (49,399 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Asthma 12,767 reports
Dyspnea 10,576 reports
Wheezing 7,131 reports
Cough 5,100 reports
Therapeutic product effect incomplete 5,051 reports
See full Mepolizumab Injection drug information
Keep checking

Other Drugs & Vitamin A

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

9Major
378Moderate
0Minor
2,442No known interaction
9 Major 378 Moderate 2,442 No interaction
Major

9 interactions

Moderate

378 interactions

Showing 60 of 378 moderate interactions — see all 378 on the Vitamin A page.

No interaction 2,442 drugs checked — show the list

We also checked Vitamin A against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,442 medications checked with no known interaction — see the full Vitamin A list.

See the full Vitamin A interactions page
See every supplement checked against Mepolizumab, ranked by severity
Evidence & sources

Vitamin A References

The 31 references that drive our Vitamin A 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. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Griffiths JK. The vitamin A paradox. J Pediatr 2000;137:604-7.. PubMed
  3. Hardman JG, Limbird LL, Molinoff PB, eds. Goodman and Gillman's The Pharmacological Basis of Therapeutics, 9th ed. New York, NY: McGraw-Hill, 1996.
  4. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  5. FDA Talk Paper. Vitamin A and birth defects (T95-56). Food and Drug Administration, U.S. Department of Health and Human Services, Rockville, MD. October 6, 1995.
  6. Russell RM. The vitamin A spectrum: from deficiency to toxicity. Am J Clin Nutr 2000;71:878-84. PubMed
  7. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academy Press, 2002.
  8. Feskanich D, Singh V, Willett WC, Colditz GA. Vitamin A intake and hip fractures among postmenopausal women. JAMA 2002;287:47-54. PubMed
  9. Melhus H, Michaelsson K, Kindmark A, et al. Excessive dietary intake of vitamin A is associated with reduced bone mineral density and increased risk for hip fracture. Ann Intern Med 1998;129:770-8. PubMed
  10. Michaelsson K, Lithell H, Vessby B, Melhus H. Serum retinol levels and the risk of fracture. N Engl J Med 2003;348:287-94.. PubMed
  11. Botterweck AA, van den Brandt PA, Goldbohm RA. Vitamins, carotenoids, dietary fiber, and the risk of gastric carcinoma: results from a prospective study after 6.3 years of follow-up. Cancer 2000;88:737-48.. DOI
  12. Meyskens FL Jr, Graham V, Chvapil M, et al. A phase I trial of beta-all-trans-retinoic acid delivered via a collagen sponge and a cervical cap for mild or moderate intraepithelial cervical neoplasia. J Natl Cancer Inst 1983;71:921-5..
  13. Hathcock JN, Hattan DG, Jenkins MY, et al. Evaluation of vitamin A toxicity. Am J Clin Nutr 1990;52:183-202.. PubMed
  14. Walters BN, Gubbay SS. Tetracycline and benign intracranial hypertension: report of five cases. Br Med J 1981;282:19-20.. PubMed
  15. Pearson MG, Littlewood SM, Bowden AN. Tetracycline and benign intracranial hypertension (letter). Br Med J 1981;282:568-9.. 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 Vitamin A and Mepolizumab Together: Common Questions

Is it safe to take Vitamin A with Mepolizumab?
We do not list a known interaction between Vitamin A and Mepolizumab. 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 Vitamin A and Mepolizumab 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 Vitamin A interact with any other medications?
Yes. Vitamin A has 387 documented drug interactions in our database — Mepolizumab is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.

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

Where next

Keep Exploring

Vitamin A monograph Uses, safety profile, and every drug interaction in one place Mepolizumab Injection drug information The full plain-English guide to this medication Mepolizumab supplement interactions Every supplement checked against Mepolizumab, 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 31 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Mepolizumab and Vitamin A?

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.