The short answer
Check which minerals your multivitamin contains. Calcium or iron can affect dolutegravir absorption when taken together while fasting. For TIVICAY tablets, those supplements may be taken together with food, or dolutegravir can be taken at least two hours before or six hours afterward.
What this answer covers
Oral mineral-containing multivitamins with oral dolutegravir. A multivitamin name does not identify the formula. Plain vitamins without the relevant minerals are not automatically assigned the mineral interaction.
- Supplement or preparation
- a multivitamin
- Medication ingredient
- dolutegravir
Has a multivitamin been tested?
Yes. One A Day Maximum reduced dolutegravir exposure by about one third in a small volunteer experiment. The authors considered that change modest and did not recommend a drug-dose adjustment. That is evidence about one formula, not permission to treat all mineral products as interchangeable.
Why do present instructions discuss spacing?
Separate calcium and iron experiments demonstrated larger exposure reductions during simultaneous fasting use. Current labeling therefore identifies multivitamins containing calcium or iron and gives the with-food or ordered-separation options. A generic two-hour gap leaves out both the six-hour direction and the food exception.
Does any supplement use mean treatment failure?
No. A later population analysis of 607 treatment-experienced adults did not predict a clinically important need for dose adjustment from the vitamin/mineral-use covariate. That analysis does not specify every formula or schedule, and does not replace the current administration instructions.
What should I check on the bottle?
Bring the full Supplement Facts panel, including prenatal products, fortified powders and any separate minerals. Check calcium, iron, magnesium and zinc amounts with your pharmacist. The complete antiretroviral product may add instructions of its own, so use the schedule for your actual medicines.
Evidence and practical considerations
Absorption & effectiveness
Check which minerals your multivitamin contains. Calcium or iron can affect dolutegravir absorption when taken together while fasting. For TIVICAY tablets, those supplements may be taken together with food, or dolutegravir can be taken at least two hours before or six hours afterward.
- Exact scope
- Oral mineral-containing multivitamins with oral dolutegravir. A multivitamin name does not identify the formula. Plain vitamins without the relevant minerals are not automatically assigned the mineral interaction. with Dolutegravir, exact RxCUI 1433868, IN. TIVICAY contains dolutegravir sodium expressed as dolutegravir active-moiety strength in its label. This provides the explicit salt-to-IN bridge. Oral tablets are the primary scope; no automatic extrapolation to another integrase inhibitor or a different combination regimen. TIVICAY PD is not interchangeable milligram for milligram.
- Medication form and route
- oral
What remains uncertain
- The multivitamin trial is product-specific and assessed at abstract level. Pooled pharmacokinetic modeling is not a controlled comparison of every fasting supplement schedule; no automatic loss of HIV control is asserted.
Factors that may matter: exact preparation and dose; food and administration order; complete antiretroviral regimen.
Read the supporting source summaries
Source 1: regulatory prescribing information
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People prescribed oral dolutegravir, including tablet and pediatric suspension formulations with separate dosing instructions.
Specifies dolutegravir two hours before or six hours after named mineral products; calcium/iron supplements have a simultaneous-with-food exception for TIVICAY. St. John’s wort co-use is to be avoided because a dosing recommendation cannot be established.
How this applies: Restricted to the preparation and conditions described in this article.
The table includes both measured and predicted interactions. It does not quantify every mineral salt, product or botanical extract. Formulations and combination tablets require their own instructions.
Source 2: primary human pharmacokinetic trial
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: Sixteen healthy participants in the antacid/multivitamin crossover experiment; a separate twelve-person omeprazole experiment.
AUC fell 74% with concurrent mixed aluminum/magnesium antacid and 26% when the antacid followed two hours later. One tested multivitamin lowered AUC 33%, judged modest by the authors.
How this applies: Restricted to the preparation and conditions described in this article.
Abstract-level assessment. Mixed antacid does not isolate aluminum or magnesium; a specific multivitamin does not represent every formula. No long-term virologic comparison.
Source 3: primary human pharmacokinetic trial
accp1.onlinelibrary.wiley.com · Source check Sep 10, 2026
Population: Twenty-four healthy adults enrolled in an open-label crossover trial; twenty-one completed the planned study.
Fasting simultaneous dosing reduced dolutegravir AUC by 39% with calcium and 54% with iron. A meal or giving dolutegravir two hours first counteracted the decrease.
How this applies: Restricted to the preparation and conditions described in this article.
Single-dose pharmacokinetics, not a long-term HIV outcome trial. Does not compare all calcium/iron salts or test the six-hours-after schedule directly. Industry-funded study; authors reported employment and stock options.
Source 4: government clinical guideline
clinicalinfo.hiv.gov · Source check Sep 10, 2026
Population: Adults and adolescents receiving antiretroviral therapy.
Supports product-specific spacing and the calcium/iron food exception; says not to coadminister St. John’s wort with dolutegravir.
How this applies: Restricted to the preparation and conditions described in this article.
Clinical guidance combines measured and predicted effects. The DTG supplement instructions specifically discuss calcium and iron; the zinc heading is not a zinc-only human experiment.
Source 5: primary population pharmacokinetic analysis
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: 607 treatment-experienced adults with HIV from four phase 2/3 trials.
The model identified mineral-supplement use as a predictor of bioavailability but did not predict a clinically relevant need for dolutegravir dose adjustment.
How this applies: Restricted to the preparation and conditions described in this article.
Abstract does not specify each formula, mineral amount or dosing schedule. Modeled covariate results do not test or negate all simultaneous-fasting exposures.
Research assessment: · Open full citations ↗
Review and change history
- Publication status
- Published research summary
- Clinical review
- Not yet recorded
| Date | Update |
|---|---|
| Article prepared | |
| Current prescribing instructions and original research checked. Article written with product-specific timing and explicit limits of the evidence. | |
| Research summary published |
Article revision: 43c0a377c2457807
This guide brings together the evidence records used by our interaction checker. Each finding retains its own preparation limits, research date, and source summaries.
Full citations require verification. Reading this answer and the source summaries does not.
Taking other supplements or medications?
Use the checker to explore your other combinations. Ask a pharmacist to review the exact products, amounts and medical conditions in your complete list.
Open the interaction checkerInformation, not medical advice. Do not change prescribed treatment based on this guide.