Drug & supplement interaction

Phosphate Salts + Rifapentine

Rifapentine brand name: Priftin.

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 Phosphate Salts and Rifapentine 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 Rifapentine states a food rule worth keeping to, and 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

Phosphate Salts and Rifapentine

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 Rifapentine and Phosphate Salts 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.

Phosphate Salts safety at a glance

Phosphate Salts overall Use caution Generally tolerated short-term in healthy people, but excess can harm the kidneys, heart, and mineral balance.
Pregnancy Likely Safe When used orally and appropriately at the recommended dietary allowance (RDA) of 1250 mg daily for individuals 14-18 years of age and 700 mg daily for those ove... Read the full pregnancy detail
Breastfeeding Likely Safe When used orally and appropriately at the recommended dietary allowance (RDA) of 1250 mg daily for individuals 14-18 years of age and 700 mg daily for those ove... 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 Rifapentine and Phosphate Salts? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Rifapentine

Interactions in our licensed database are recorded against drug classes, not just single drug names. Rifapentine is filed under 4 classifications — including cytochrome p450 2c9 (cyp2c9) inducers, cytochrome p450 3a4 (cyp3a4) inducers, antibiotic drugs. Phosphate Salts has documented interactions with 3 drug classes — the most serious being erdafitinib (balversa) (major), futibatinib (lytgobi) (major) and bisphosphonates (moderate) — and none of Rifapentine’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Phosphate Salts Does Interact With Other Medications

Phosphate Salts has 2 major, 10 moderate known drug interactions in our database — Rifapentine isn’t one of them. If you take anything else, check it against the full list below.

Major 2 Moderate 10 No known interaction 2,818 (incl. Rifapentine)
Taking anything else?

Check Another of Your Medications Against Phosphate Salts

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

What to actually watch for

No Interaction Found — But Data Suggests Phosphate Salts and Rifapentine 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. 3 of them are worth acting on rather than waiting out — marked below.

  • High potassium Worth acting on Additional detail

    Phosphate Salts

    “Orally, phosphate salts can cause fluid and electrolyte disturbances including hyperphosphatemia and hypocalcemia, and extraskeletal calcification. Potassium phosphates can cause hyperkalemia. Sodium phosphates can cause hypernatremia and hypokalemia (15,2494,2495,2496,2497,107008).

    Rectally, phosphate salts can cause fluid and electrolyte disturbances including hyperphosphatemia and hypocalcemia (15,112922).

    Deaths…”

    Phosphate Salts · Natural Medicines adverse-effect record, reported in hypocalcemia.

    6 sources cited
    1. 15. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
    2. 2494. Hill AG, Teo W, Still A, et al. Cellular potassium depletion predisposes to hypokalaemia after oral sodium phosphate. Aust N Z J Surg 1998;68:856-8. PubMed
    3. 2495. Clarkston WK, Tsen TN, Dies DF, et al. Oral sodium phosphate versus sulfate-free polyethylene glycol electrolyte lavage solution in outpatient preparation for colonoscopy: a prospective comparison. Gastrointest Endosc 1996;43:42-8. PubMed
    4. 2496. Fine A, Patterson J. Severe hyperphosphatemia following phosphate administration for bowel preparation in patients with renal failure: two cases and a review of the literature. Am J Kidney Dis 1997;29:103-5. PubMed
    5. 2497. DiPalma JA, Buckley SE, Warner BA, et al. Biochemical effects of oral sodium phosphate. Dig Dis Sci 1996;41:749-53. PubMed
    6. 107008. Hung SY, Chen HC, Ke TW, et al. Noninferiority clinical trial comparing the bowel cleansing efficacy of sodium phosphate tablets (Quiklean(®)) with a polyethylene glycol/bisacodyl kit. World J Gastroenterol 2021;27(5):428-441.

    Rifapentine

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

  • Anemia Worth acting on Additional detail

    Phosphate Salts

    “Orally, use of sodium phosphate for bowel cleansing has been associated with an increased risk of acute kidney injury in some patients. However, a pooled analysis of clinical research suggests that results are not consistent for all patients.”

    Phosphate Salts · Natural Medicines adverse-effect record, reported in anemia.

    3 sources cited
    1. 93863. Choi NK, Lee J, Chang Y, Kim YJ, Kim JY, Song HJ, Shin JY, Jung SY, Choi Y, Lee JH, Park BJ. Acute renal failure following oral sodium phosphate bowel preparation: a nationwide case-crossover study. Endoscopy. 2014 Jun;46(6):465-70. PubMed
    2. 93864. Brunelli SM. Association between oral sodium phosphate bowel preparations and kidney injury: a systematic review and meta-analysis. Am J Kidney Dis. 2009 Mar;53(3):448-56. PubMed
    3. 93865. Schaefer M, Littrell E, Khan A, Patterson ME. Estimated GFR Decline Following Sodium Phosphate Enemas Versus Polyethylene Glycol for Screening Colonoscopy: A Retrospective Cohort Study. Am J Kidney Dis. 2016 Apr;67(4):609-16. PubMed

    Rifapentine

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

  • A severe allergic reaction Worth acting on Additional detail

    Phosphate Salts

    “Orally, a case of allergic acute coronary syndrome (i.e., Kounis syndrome) is reported in a 43-year-old female after ingesting a specific sodium phosphate laxative product (Travad oral). She presented with maculopapular rash that progressed to anaphylaxis and a non-ST elevation acute coronary syndrome. The patient recovered after hospitalization for 3 days with medical management.”

    Phosphate Salts · Natural Medicines adverse-effect record, reported in myocardial infarction (mi).

    1 source cited
    1. 112894. Zuluaga-Gómez M, González-Arroyave D, Ardila CM. Kounis Syndrome Secondary to Laxative Administration. Case Rep Med 2022;2022:6087176. PubMed

    Rifapentine

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

  • Constipation Additional detail

    Phosphate Salts

    “Orally, phosphate salts can cause gastrointestinal irritation, nausea, abdominal pain, bloating, anal irritation, and vomiting (15,2494,2495,2496,2497,93846,93848,93850,93851,93853,107008). Sodium and potassium phosphates can cause diarrhea (15). Aluminum phosphate can cause constipation (15).”

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

    6 sources cited
    1. 15. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
    2. 2494. Hill AG, Teo W, Still A, et al. Cellular potassium depletion predisposes to hypokalaemia after oral sodium phosphate. Aust N Z J Surg 1998;68:856-8. PubMed
    3. 2495. Clarkston WK, Tsen TN, Dies DF, et al. Oral sodium phosphate versus sulfate-free polyethylene glycol electrolyte lavage solution in outpatient preparation for colonoscopy: a prospective comparison. Gastrointest Endosc 1996;43:42-8. PubMed
    4. 2496. Fine A, Patterson J. Severe hyperphosphatemia following phosphate administration for bowel preparation in patients with renal failure: two cases and a review of the literature. Am J Kidney Dis 1997;29:103-5. PubMed
    5. 2497. DiPalma JA, Buckley SE, Warner BA, et al. Biochemical effects of oral sodium phosphate. Dig Dis Sci 1996;41:749-53. PubMed
    6. 93846. Ell C, Fischbach W, Layer P, Halphen M. Randomized, controlled trial of 2 L polyethylene glycol plus ascorbate components versus sodium phosphate for bowel cleansing prior to colonoscopy for cancer screening. Curr Med Res Opin. 2014 Dec;30(12):2493-503. PubMed

    Rifapentine

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

  • Stomach pain / Diarrhea / Vomiting Additional detail

    Phosphate Salts

    “Orally, intravenously, and rectally, phosphate salts are generally well tolerated when used appropriately and/or as prescribed.

    Most Common Adverse Effects:

    Orally: Abdominal pain, anal irritation, bloating, diarrhea, headache, gastrointestinal irritation, hyperphosphatemia, hypocalcemia, malaise, nausea, sleep disturbance, and vomiting.

    Rectally: Hyperphosphatemia and hypocalcemia.

    Serious Adverse Effects (Rare):

    Or…”

    Phosphate Salts · Natural Medicines adverse-effect record, reported in cluster headache.

    Rifapentine

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

  • Tiredness / Headache Additional detail

    Phosphate Salts

    “Orally, phosphate salts can commonly cause malaise. Headaches and sleep disturbance may also occur.”

    Phosphate Salts · Natural Medicines adverse-effect record, reported in insomnia.

    3 sources cited
    1. 93846. Ell C, Fischbach W, Layer P, Halphen M. Randomized, controlled trial of 2 L polyethylene glycol plus ascorbate components versus sodium phosphate for bowel cleansing prior to colonoscopy for cancer screening. Curr Med Res Opin. 2014 Dec;30(12):2493-503. PubMed
    2. 93848. Jung YS, Lee CK, Kim HJ, Eun CS, Han DS, Park DI. Randomized controlled trial of sodium phosphate tablets vs polyethylene glycol solution for colonoscopy bowel cleansing. World J Gastroenterol. 2014 Nov 14;20(42):15845-51. PubMed
    3. 93851. Manukyan MN, Tolan K, Severge U, Attaallah W, Kebudi A, Cingi A. Prospective randomized comparison of oral sodium phosphate and sennoside A+B calcium lavage for colonoscopy preparation. Surg Laparosc Endosc Percutan Tech. 2011 Apr;21(2):90-3. PubMed

    Rifapentine

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

  • A skin rash Additional detail

    Phosphate Salts

    Recorded for Phosphate Salts in the same Natural Medicines adverse-effect record shown under A severe allergic reaction above.

    Rifapentine

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

Showing the 10 most notable of 11 shared effects — ranked by how unusual each one is, not just whether both lists mention it.

Reported for Phosphate Salts but not commonly for Rifapentine: an electrolyte imbalance, kidney problems, trouble sleeping and low potassium.

Effects for Rifapentine come from the ADVERSE REACTIONS section of its FDA label; effects for Phosphate Salts come from the Natural Medicines adverse-effect record, quoted above. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Special populations

Phosphate Salts in Pregnancy & Breastfeeding

Pregnancy And Lactation Likely Safe

When used orally and appropriately at the recommended dietary allowance (RDA) of 1250 mg daily for individuals 14-18 years of age and 700 mg daily for those over 18 years of age. ...when sodium phosphate is used rectally and appropriately short-term. ...when used intravenously. Intravenous potassium phosphate is an FDA-approved prescription drug.

Pregnancy And Lactation Possibly Unsafe

When phosphate (expressed as phosphorus) intake exceeds the tolerable upper intake level (UL). Hyperphosphatemia, resulting in electrolyte disturbances, alterations in calcium homeostasis, and calcification of nonskeletal tissues, may occur. The UL during pregnancy is 3.5 grams daily. During lactation, the UL is 4 grams 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

How to take them

Some Rifapentine Products Have a Food Rule — Phosphate Salts Should Not Break It

At least one FDA label for a product containing Rifapentine says to take it with food. If you take Phosphate Salts on an empty stomach out of habit, keep them separate — and take Rifapentine with a meal where the label says to.

This may not be true of your version. Food instructions belong to the product, not the ingredient: two Rifapentine 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.

( 2.2 ) Take with food.

From the Dosage and Administration section of the FDA label we read for Rifapentine — where that label names a specific product, the instruction is that product's. Read the label on DailyMed ›

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.

Everything else you take

See Every Supplement That Interacts With Rifapentine

This page covers Phosphate Salts only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Rifapentine page lists 64 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Alkanna (moderate), Alpine Ragwort (moderate), Bacillus Coagulans (moderate) and Bacillus Subtilis (moderate).

By severity: 1 major · 53 moderate · 10 minor.

From our pharmacist’s overview on the Rifapentine page

“Rifapentine (Priftin) treats tuberculosis and is often dosed just once or twice a week, so a single blunted dose costs more than it would with a daily pill. That is why I read this list of 64 interacting supplements as a real warning rather than routine fine print.”

Reviewed by 2 · Jul 18, 2026

Open the Rifapentine interaction page

One more smart check

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

We hold 6 real supplement products containing Phosphate Salts, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Phosphate Salts. Even though Phosphate Salts itself has no known interaction with Rifapentine, 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 Phosphate Salts and Rifapentine 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 Phosphate Salts
Steady interest

#1,136 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Rifapentine
Steady interest

#2,684 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 Phosphate Salts reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Phosphate Salts and Rifapentine 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 Phosphate Salts

What is Phosphate Salts?

  • Low blood phosphate levels (hypophosphatemia)
  • Bowel preparation/laxative use
  • Athletic performance ('phosphate loading')
  • Preventing certain kidney stones
  • Calcium supplementation balance

Phosphate salts are mineral compounds used mainly to correct low phosphate levels, as laxatives, and sometimes by athletes. Most people who eat a normal diet already get plenty of phosphate and do not need a supplement. Because too much phosphate can be dangerous—especially for people with kidney disease—use these products only under the guidance of a doctor or pharmacist.

Mineral salts (not a plant) · Tablets, capsules, powders, oral solutions, effervescent tablets, and intravenous (medical) solutions

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

Phosphate Salts: dosing

There is no single standard supplement dose that fits everyone, because the right amount depends on why it is being used—correcting a deficiency, bowel prep, or another reason—and on your kidney function and blood levels.Phosphate products used in hospitals or for bowel prep are dosed by a healthcare provider. For over-the-counter products, follow the label exactly and do not take more than directed.

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

Read the full Phosphate Salts monograph & all interactions
Medication

About Rifapentine

What Is Rifapentine Used For?

Brand name: Priftin

Rifapentine tablets — sold as Priftin and as rifapentine tablets — are used to treat two forms of tuberculosis caused by Mycobacterium tuberculosis. For active pulmonary TB (a live TB infection in the lungs), it is approved for adults and children 12 years and older. It must always be combined with other anti-TB drugs — never taken alone.

For latent tuberculosis infection (LTBI) — where TB bacteria are in the body but not yet causing illness — it is approved for adults and children 2 years and older who are at high risk of the infection becoming active. For LTBI, it is always taken together with isoniazid, once weekly for 12 weeks. Active TB disease must be ruled out before starting LTBI treatment.

Most-Reported Side Effects for Rifapentine

From FAERS, the FDA’s public side-effect reporting system (509 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Fever 66 reports
Nausea 52 reports
Fatigue 42 reports
Hypertension 40 reports
Vomiting 40 reports
See full Rifapentine drug information
Keep checking

Other Drugs & Phosphate Salts

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

2Major
10Moderate
0Minor
2,817No known interaction
2 Major 10 Moderate 2,817 No interaction
Major

2 interactions

Moderate

10 interactions

No interaction 2,817 drugs checked — show the list

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

Showing the 60 most looked-up of 2,817 medications checked with no known interaction — see the full Phosphate Salts list.

See the full Phosphate Salts interactions page
See every supplement checked against Rifapentine, ranked by severity
Evidence & sources

Phosphate Salts References

The 23 references that drive our Phosphate Salts 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. Hill AG, Teo W, Still A, et al. Cellular potassium depletion predisposes to hypokalaemia after oral sodium phosphate. Aust N Z J Surg 1998;68:856-8. PubMed
  3. Clarkston WK, Tsen TN, Dies DF, et al. Oral sodium phosphate versus sulfate-free polyethylene glycol electrolyte lavage solution in outpatient preparation for colonoscopy: a prospective comparison. Gastrointest Endosc 1996;43:42-8. PubMed
  4. Fine A, Patterson J. Severe hyperphosphatemia following phosphate administration for bowel preparation in patients with renal failure: two cases and a review of the literature. Am J Kidney Dis 1997;29:103-5. PubMed
  5. DiPalma JA, Buckley SE, Warner BA, et al. Biochemical effects of oral sodium phosphate. Dig Dis Sci 1996;41:749-53. PubMed
  6. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride. Washington, DC: National Academy Press, 1999. Available at: http://books.nap.edu/books/0309063507/html/index.html.
  7. Campisi P, Badhwar V, Morin S, Trudel JL. Postoperative hypocalcemic tetany caused by Fleet Phospho-Soda preparation in a patient taking alendronate sodium. Dis Colon Rectum 1999;42:1499-501. DOI
  8. Ell C, Fischbach W, Layer P, Halphen M. Randomized, controlled trial of 2 L polyethylene glycol plus ascorbate components versus sodium phosphate for bowel cleansing prior to colonoscopy for cancer screening. Curr Med Res Opin. 2014 Dec;30(12):2493-503. PubMed
  9. Jung YS, Lee CK, Kim HJ, Eun CS, Han DS, Park DI. Randomized controlled trial of sodium phosphate tablets vs polyethylene glycol solution for colonoscopy bowel cleansing. World J Gastroenterol. 2014 Nov 14;20(42):15845-51. PubMed
  10. Lee SH, Lee DJ, Kim KM, Seo SW, Kang JK, Lee EH, Lee DR. Comparison of the efficacy and safety of sodium phosphate tablets and polyethylene glycol solution for bowel cleansing in healthy Korean adults. Yonsei Med J. 2014 Nov;55(6):1542-55. PubMed
  11. Manukyan MN, Tolan K, Severge U, Attaallah W, Kebudi A, Cingi A. Prospective randomized comparison of oral sodium phosphate and sennoside A+B calcium lavage for colonoscopy preparation. Surg Laparosc Endosc Percutan Tech. 2011 Apr;21(2):90-3. PubMed
  12. van Vugt van Pinxteren MW, van Kouwen MC, van Oijen MG, van Achterberg T, Nagengast FM. A prospective study of bowel preparation for colonoscopy with polyethylene glycol-electrolyte solution versus sodium phosphate in Lynch syndrome: a randomized trial. F PubMed
  13. Choi NK, Lee J, Chang Y, Kim YJ, Kim JY, Song HJ, Shin JY, Jung SY, Choi Y, Lee JH, Park BJ. Acute renal failure following oral sodium phosphate bowel preparation: a nationwide case-crossover study. Endoscopy. 2014 Jun;46(6):465-70. PubMed
  14. Brunelli SM. Association between oral sodium phosphate bowel preparations and kidney injury: a systematic review and meta-analysis. Am J Kidney Dis. 2009 Mar;53(3):448-56. PubMed
  15. Schaefer M, Littrell E, Khan A, Patterson ME. Estimated GFR Decline Following Sodium Phosphate Enemas Versus Polyethylene Glycol for Screening Colonoscopy: A Retrospective Cohort Study. Am J Kidney Dis. 2016 Apr;67(4):609-16. 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 Phosphate Salts and Rifapentine Together: Common Questions

Is it safe to take Phosphate Salts with Rifapentine?
We do not list a known interaction between Phosphate Salts and Rifapentine. 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 Phosphate Salts and Rifapentine have any of the same side effects?
Yes — our sources link each of them separately to 10 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.
Should I take Phosphate Salts and Rifapentine at the same time of day?
At least one FDA label for a product containing Rifapentine says to take it with food. If you take Phosphate Salts on an empty stomach out of habit, keep them separate and take Rifapentine with a meal where the label says to. Food instructions belong to the product rather than the ingredient — two Rifapentine products can differ — so check the directions on your own box. This is about absorption, not an interaction.
How was the Phosphate Salts and Rifapentine combination checked?
Interactions in our licensed database are recorded against drug classes. Rifapentine is filed under 4 classifications, and Phosphate Salts has documented interactions with 3 drug classes — none of Rifapentine's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Phosphate Salts interact with any other medications?
Yes. Phosphate Salts has 12 documented drug interactions in our database — Rifapentine is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Rifapentine interact with any supplements?
Yes. Rifapentine has documented interactions with 64 supplements in our database — Phosphate Salts is not one of them. The Rifapentine 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

Phosphate Salts monograph Uses, safety profile, and every drug interaction in one place Rifapentine drug information The full plain-English guide to this medication Rifapentine supplement interactions Every supplement checked against Rifapentine, 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 23 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Rifapentine and Phosphate Salts?

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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.