Drug & supplement interaction

Vitamin D + Asfotase Alfa

Asfotase Alfa brand name: Strensiq.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Vitamin D and Asfotase Alfa 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

Vitamin D and Asfotase Alfa

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 Asfotase Alfa and Vitamin D 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 D safety at a glance

Vitamin D overall Generally safe Vitamin D is generally safe at recommended doses, but very high doses over time can cause toxicity.
Pregnancy Likely Safe When used orally and appropriately. Vitamin D is safe when used in doses below the tolerable upper intake level (UL) of 4000 IU (100 mcg) daily. Read the full pregnancy detail
Breastfeeding Likely Safe When used orally and appropriately. Vitamin D is safe when used in doses below the tolerable upper intake level (UL) of 4000 IU (100 mcg) daily. 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 Asfotase Alfa and Vitamin D? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
Keep it in perspective

Vitamin D Does Interact With Other Medications

Vitamin D has 80 moderate, 635 minor known drug interactions in our database — Asfotase Alfa isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Vitamin D

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

What to actually watch for

No Interaction Found — But Data Suggests Vitamin D and Asfotase Alfa 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.

  • Itching Additional detail

    Vitamin D

    “Vitamin D intoxication can occur when vitamin D supplements are taken orally in excessive doses. Advanced symptoms may include decreased libido. Vaginal discharge and itching have been reported in a clinical trial following oral use.”

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

    2 sources cited
    1. 10142. Koutkia P, Chen TC, Holick MF. Vitamin D intoxication associated with an over-the-counter supplement. N Engl J Med 2001;345:66-7. PubMed
    2. 91348. Turner AN, Carr Reese P, Fields KS, Anderson J, Ervin M, Davis JA, Fichorova RN, Roberts MW, Klebanoff MA, Jackson RD. A blinded, randomized controlled trial of high-dose vitamin D supplementation to reduce recurrence of bacterial vaginosis. Am J Obstet G PubMed

    Asfotase Alfa

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

  • Vomiting Additional detail

    Vitamin D

    “Orally, vitamin D may cause dry mouth. In clinical research, intake of vitamin D 50,000 IU weekly for 4 weeks followed by 50,000 IU monthly for 5 months thereafter was associated with a 3.7-fold increase in reports of dry mouth compared with placebo.Vitamin D intoxication can occur when vitamin D supplements are taken orally in excessive doses. Symptoms of vitamin D toxicity include pancreatitis.”

    Vitamin D · Natural Medicines adverse-effect record, reported in dry mouth.

    4 sources cited
    1. 91348. Turner AN, Carr Reese P, Fields KS, Anderson J, Ervin M, Davis JA, Fichorova RN, Roberts MW, Klebanoff MA, Jackson RD. A blinded, randomized controlled trial of high-dose vitamin D supplementation to reduce recurrence of bacterial vaginosis. Am J Obstet G PubMed
    2. 10142. Koutkia P, Chen TC, Holick MF. Vitamin D intoxication associated with an over-the-counter supplement. N Engl J Med 2001;345:66-7. PubMed
    3. 84433. Carlton, S., Clopton, D., and Cappuzzo, K. A. Vitamin D deficiency: appropriate replenishment therapies and the effects of vitamin D toxicity. Consult Pharm 2010;25(3):171-177. PubMed
    4. 104624. Murai IH, Fernandes AL, Sales LP, et al. Effect of a single high dose of vitamin D3 on hospital length of stay in patients with moderate to severe COVID-19: A randomized clinical trial. JAMA. 2021.

    Asfotase Alfa

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

Reported for Vitamin D but not commonly for Asfotase Alfa: a change in sex drive, kidney problems, kidney stones and pancreatitis.

Effects for Asfotase Alfa come from the ADVERSE REACTIONS section of its FDA label; effects for Vitamin D come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 9,959 voluntary FDA FAERS reports for Asfotase Alfa 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 D in Pregnancy & Breastfeeding

Pregnancy Likely Safe

When used orally and appropriately. Vitamin D is safe when used in doses below the tolerable upper intake level (UL) of 4000 IU (100 mcg) daily.

Pregnancy Possibly Unsafe

When used orally in excessive amounts. Tell patients not to use doses above the tolerable upper intake level (UL) of 4000 IU (100 mcg) daily. Hypercalcemia during pregnancy due to excessive vitamin D intake can lead to several fetal adverse effects, including suppression of parathyroid hormone, hypocalcemia, tetany, seizures, aortic valve stenosis, retinopathy, and mental and/or physical developmental delay.

Lactation Likely Safe

When used orally and appropriately. Vitamin D is safe when used in doses below the tolerable upper intake level (UL) of 4000 IU (100 mcg) daily.

Lactation Possibly Unsafe

When used orally in excessive amounts. Tell patients not to use doses above the tolerable upper intake level (UL) of 4000 IU (100 mcg) daily.

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

Overlapping uses

What Asfotase Alfa Is Prescribed For, and What Vitamin D Has Been Studied For

These two come up together because they touch the same health topic — not because they do the same job. Asfotase Alfa is a prescription medicine with approved uses on its FDA label. Vitamin D is a supplement: what follows is what researchers have looked at it for, and how strong that evidence is.

Asfotase Alfa is prescribed for: Strensiq (asfotase alfa), given as a subcutaneous injection, is approved to treat perinatal/infantile-onset and juvenile-onset hypophosphatasia (HPP) — a rare genetic disorder in which the body lacks enough of an enzyme called TNSALP, leading to problems with bone mineralization, rickets, bone deformity, and muscle weakness. HPP can present at birth or in childhood. Strensiq is the specific brand approved for these forms of the disease. Safety and effectiveness have been established in pediatric patients across both onset types.

Vitamin D has been studied for:

  • Rickets Natural Medicines rates the evidence for Vitamin D: Effective Read what the research shows

    Vitamin D for rickets

    Oral vitamin D prevents and treats rickets.

Effectiveness ratings and the research summaries above are the verbatim record from the Natural Medicines database, which grades evidence from “Effective” down to “Insufficient Reliable Evidence To Rate”. A rating below the top of that scale means researchers have looked at it — not that it works, and never that it can stand in for a prescribed medicine. Do not stop or replace Asfotase Alfa on your own; if you are taking Vitamin D for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

From our Q&A

Questions About Vitamin D or Asfotase Alfa

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 D or Asfotase Alfa, 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 D as Part of a Dietary Supplement Product? Check It for Interactions

We hold 26,930 real supplement products containing Vitamin D, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Vitamin D. Even though Vitamin D itself has no known interaction with Asfotase Alfa, 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 D and Asfotase Alfa 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 D
Top 10

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

29 days ago today
Medication Asfotase Alfa
Top half

#709 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 D reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Vitamin D and Asfotase Alfa 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 Vitamin D

What is Vitamin D?

Vitamin D
  • Bone health and osteoporosis
  • Correcting vitamin D deficiency
  • Immune system support
  • Muscle strength in older adults
  • General supplementation when sun exposure is low

Vitamin D is a fat-soluble vitamin that helps your body absorb calcium and is important for healthy bones, muscles, and immune function. Many people, especially those with low sun exposure, benefit from supplementation, but more is not always better and very high doses can be harmful. Ask your pharmacist or doctor whether a blood test and supplement make sense for you.

Not applicable (a vitamin, not a plant part) · Tablets, capsules, softgels, liquid drops, chewables, and injections

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

Vitamin D: dosing

The right dose of vitamin D depends on your age, blood level, health conditions, and how much sun and dietary vitamin D you get. There is no single dose that fits everyone.Supplements come in different strengths, and doses are measured in international units (IU) or micrograms (mcg). Some people only need a small daily amount, while those who are deficient may need a higher, supervised dose for a period of time.The best approach is to follow the directions on the product label or the advice of your pharmacist or doctor. A simple blood test can show whether you are low and help guide the right dose.

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

Read the full Vitamin D monograph & all interactions
Medication

About Asfotase Alfa

What Is Asfotase Alfa Used For?

Brand name: Strensiq

Strensiq (asfotase alfa), given as a subcutaneous injection, is approved to treat perinatal/infantile-onset and juvenile-onset hypophosphatasia (HPP) — a rare genetic disorder in which the body lacks enough of an enzyme called TNSALP, leading to problems with bone mineralization, rickets, bone deformity, and muscle weakness.

HPP can present at birth or in childhood. Strensiq is the specific brand approved for these forms of the disease. Safety and effectiveness have been established in pediatric patients across both onset types.

Most-Reported Side Effects for Asfotase Alfa

From FAERS, the FDA’s public side-effect reporting system (9,959 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Injection site pain 1,327 reports
Fatigue 952 reports
Injection site erythema 869 reports
Injection site reaction 747 reports
Arthralgia 665 reports
See full Asfotase Alfa drug information
Keep checking

Other Drugs & Vitamin D

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

0Major
80Moderate
635Minor
2,114No known interaction
Moderate

80 interactions

Showing 60 of 80 moderate interactions — see all 80 on the Vitamin D page.

Minor

635 interactions

Showing 60 of 635 minor interactions — see all 635 on the Vitamin D page.

No interaction 2,114 drugs checked — show the list
Evidence & sources

Vitamin D References

The 26 references that drive our Vitamin D 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. Tatro DS, ed. Drug Interactions Facts. Facts and Comparisons Inc., St. Louis, MO. 1999.
  3. Koutkia P, Chen TC, Holick MF. Vitamin D intoxication associated with an over-the-counter supplement. N Engl J Med 2001;345:66-7. PubMed
  4. Bar-Or D, Yoel G. Calcium and calciferol antagonize effect of verapamil in atrial fibrillation. Br Med J 1981;282:1585-6.
  5. Demontis R, Leflon A, Fournier A, et al. 1 alpha(OH) vitamin D3 increases plasma aluminum in hemodialyzed patients taking AI(OH)3. Clin Nephrol 1986;26:146-9.
  6. Crowe M, Wollner L, Griffiths RA. Hypercalcemia following vitamin D and thiazide therapy in the elderly. Practitioner 1984;228:312-3.
  7. Parfitt AM. Thiazide-induced hypercalcemia in vitamin D-treated hypoparathyroidism. Ann Intern Med 1972;77:557-63. PubMed
  8. Thiazide diuretics and the risk of osteoporosis. Pharmacist's Letter/Prescriber's Letter 2003;19(11):191105.
  9. Moon J. The role of vitamin D in toxic metal absorption. J Am Coll Nutr 1994;13:559-64.
  10. Demontis R, Reissi D, Noel C, et al. Indirect clinical evidence that 1alphaOH vitamin D<SUB>3</SUB> increases the intestinal absorption of aluminum. Clin Nephrol 1989;31:123-7.
  11. Adler AJ, Berlyne GM. Duodenal aluminum absorption in the rat: effect of vitamin D. Am J Physiol 1985;249:G209-13. PubMed
  12. Schwartz JB. Effects of vitamin D supplementation in atorvastatin-treated patients: A new drug interaction with an unexpected consequence. Clin Pharmacol Ther 2009;85:198-203. PubMed
  13. Dietary reference intakes for calcium and vitamin D. Institute of Medicine, November 30, 2010. Available at: http://www.iom.edu/~/media/Files/Report%20Files/2010/Dietary-Reference-Intakes-for-Calcium-and-Vitamin-D/Vitamin%20D%20and%20Calcium%202010%20Repo
  14. Cox KA, Dunn MA. Aluminum toxicity alters the regulation of calbindin-D28k protein and mRNA expression in chick intestine. J Nutr 2001;131:2007-13. PubMed
  15. Escribano, J., Balaguer, A., Pagone, F., Feliu, A., and Roque, I. Figuls. Pharmacological interventions for preventing complications in idiopathic hypercalciuria. Cochrane.Database.Syst.Rev. 2009;(1):CD004754. 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 D and Asfotase Alfa Together: Common Questions

Is it safe to take Vitamin D with Asfotase Alfa?
We do not list a known interaction between Vitamin D and Asfotase Alfa. 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 D and Asfotase Alfa have any of the same side effects?
Yes — our sources link each of them separately to 2 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.
Are Vitamin D and Asfotase Alfa used for the same thing?
They overlap in purpose, which usually means the real question is whether you need both rather than whether they are safe together. This page lists the shared uses and how strong the evidence is for Vitamin D in each. That is a conversation for your prescriber, especially if Asfotase Alfa is being adjusted to a target.
Does Vitamin D interact with any other medications?
Yes. Vitamin D has 715 documented drug interactions in our database — Asfotase Alfa 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

Still Have a Question About Asfotase Alfa and Vitamin D?

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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.