Sulfur + Glycerol Phenylbutyrate
Glycerol Phenylbutyrate brand name: Ravicti.
We found no known interaction between Sulfur and Glycerol Phenylbutyrate 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 Glycerol Phenylbutyrate 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.
Sulfur and Glycerol Phenylbutyrate
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 Glycerol Phenylbutyrate and Sulfur 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 Sulfur at all — not against Glycerol Phenylbutyrate, 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.
Sulfur safety at a glance
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.
Sulfur in Pregnancy & Breastfeeding
When applied topically and appropriately, short-term. Topical products containing sulfur in concentrations up to 6% have been safely applied nightly for up to 6 nights. There is insufficient reliable information available about the safety of sulfur when used orally; 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
Some Glycerol Phenylbutyrate Products Have a Food Rule — Sulfur Should Not Break It
At least one FDA label for a product containing Glycerol Phenylbutyrate says to take it with food. If you take Sulfur on an empty stomach out of habit, keep them separate — and take Glycerol Phenylbutyrate 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 Glycerol Phenylbutyrate 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.
Instruct patients to take glycerol phenylbutyrate oral liquid with food or formula and to administer directly into the mouth via oral syringe.
From the Dosage and Administration section of the FDA label we read for Glycerol Phenylbutyrate — 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.
See Every Supplement That Interacts With Glycerol Phenylbutyrate
This page covers Sulfur only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Glycerol Phenylbutyrate page lists 17 supplements it has a documented interaction with, worst first, each one explained.
The most serious there right now: Activated Charcoal (major), Coffee Charcoal (moderate), European Mandrake (moderate), Glucomannan (moderate) and Guar Gum (moderate).
By severity: 1 major · 7 moderate · 9 minor.
From our pharmacist’s overview on the Glycerol Phenylbutyrate page
“Ravicti (glycerol phenylbutyrate) pulls ammonia out of the blood in people with urea cycle disorders, so a dose that never gets absorbed is not a small problem, it can let ammonia climb toward dangerous levels. That is why this list deserves real attention even though it is short.”
Reviewed by 2 · Jul 18, 2026
Taking Sulfur as Part of a Dietary Supplement Product? Check It for Interactions
We hold 492 real supplement products containing Sulfur, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Sulfur. Even though Sulfur itself has no known interaction with Glycerol Phenylbutyrate, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:
Where Sulfur and Glycerol Phenylbutyrate 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.
#361 of 1,452 supplements looked up here in the last 7 days
#170 of 2,830 medications looked up here in the last 7 days
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 Sulfur reference on this page ↓
- Freshness: we automatically re-check this combination every week — this pair was last verified September 27, 2026. The Sulfur and Glycerol Phenylbutyrate 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.
About Sulfur
What is Sulfur?
- Acne and oily skin
- Rosacea
- Seborrheic dermatitis and dandruff
- Scabies and other skin parasites
- Joint pain (as MSM)
Sulfur is a mineral used mainly in topical skin products for acne, rosacea, dandruff, and certain skin infections, and has a long history in dermatology. Topical sulfur is generally well tolerated but can be drying and smelly; oral sulfur supplements like MSM are taken for joint pain, though the evidence is limited. Talk with your pharmacist or doctor before starting any sulfur product.
Elemental sulfur (mineral) or sulfur-containing compounds · Topical creams, ointments, lotions, soaps, and bath products; oral MSM (methylsulfonylmethane) capsules and powders
An interaction check asks whether these two react with each other — it does not ask whether Sulfur is a good idea for someone in your situation. Here is what our Sulfur record says about it on its own.
Sulfur: dosing
There is no single standardized dose for sulfur, and the right amount depends on the product and how it is used. Topical products contain different concentrations of sulfur, so always follow the directions on the label.For oral supplements like MSM, there is no firmly established dose.
From our Sulfur monograph — the full record covers uses, side effects and every documented interaction.
About Glycerol Phenylbutyrate
What Is Glycerol Phenylbutyrate Used For?
Brand name: Ravicti
Glycerol phenylbutyrate oral liquid — available as the brand Ravicti and as a generic — is used for the long-term (chronic) management of urea cycle disorders (UCDs). UCDs are rare inherited conditions where the body cannot properly convert ammonia into urea, causing toxic ammonia levels to build up in the blood and brain.
It is used in patients whose ammonia cannot be controlled by a low-protein diet and/or amino acid supplements alone. It must always be used alongside dietary protein restriction and, in some cases, additional dietary supplements such as essential amino acids, arginine, or citrulline. It is not for treating a sudden, severe spike in ammonia (acute hyperammonemia), and its safety and effectiveness for N-acetylglutamate synthase (NAGS) deficiency have not been established.
Other Drugs & Sulfur
Browse every other medication we’ve checked against Sulfur — both the ones with a known interaction and the ones without. Select any drug for the full detail.
No drugs match “”.
No interaction 2,829 drugs checked — show the list
We also checked Sulfur against these medications and found no known interaction in our sources. Open any page to confirm.
- Apixaban ›
- Levothyroxine ›
- Amlodipine ›
- Methylphenidate ›
- Warfarin ›
- Abemaciclib ›
- Ivermectin ›
- Testosterone ›
- Sertraline ›
- Acetaminophen ›
- Losartan Potassium ›
- Aspirin ›
- Rosuvastatin ›
- Metoprolol ›
- Escitalopram ›
- Clopidogrel ›
- Rivaroxaban ›
- Atorvastatin ›
- Isotretinoin ›
- Tirzepatide ›
- Warfarin Sodium ›
- Ibuprofen ›
- Methamphetamine ›
- Amlodipine Besylate ›
- Docusate ›
- Sumatriptan ›
- Valacyclovir ›
- Tadalafil ›
- Hydroxyurea ›
- Prednisone ›
- Metformin ›
- Semaglutide ›
- Lisdexamfetamine ›
- Amitriptyline ›
- Propranolol ›
- Amphetamine ›
- Amoxicillin ›
- Methotrexate ›
- Lisinopril ›
- Levothyroxine, Liothyronine ›
- Bupropion ›
- Fluoxetine ›
- Bendamustine ›
- Azithromycin ›
- Pregabalin ›
- Doxycycline ›
- Dextroamphetamine ›
- Lamotrigine ›
- Gabapentin ›
- Acyclovir ›
- Naproxen ›
- Quetiapine ›
- Clonazepam ›
- Buspirone ›
- Acetaminophen, Aspirin, Caffeine ›
- Omeprazole ›
- Duloxetine ›
- Letrozole ›
- Citalopram ›
- Acetaminophen, Codeine ›
Showing the 60 most looked-up of 2,829 medications checked with no known interaction — see the full Sulfur list.
Sulfur References
The 17 references that drive our Sulfur 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.
- Blum, J. E. and Coe, F. L. Metabolic acidosis after sulfur ingestion. N Engl J Med 1977;297(16):869-70. PubMed
- Roos, T. C., Alam, M., Roos, S., Merk, H. F., and Bickers, D. R. Pharmacotherapy of ectoparasitic infections. Drugs 2001;61(8):1067-88. PubMed
- Diaz, M., Cazorla, D., and Acosta, M. [Efficacy, safety and acceptability of precipitated sulphur petrolatum for topical treatment of scabies at the city of Coro, Falcon State, Venezuela]. Rev Invest Clin 2004;56(5):615-22.
- Schmiedel, V. and Klein, P. A complex homeopathic preparation for the symptomatic treatment of upper respiratory infections associated with the common cold: An observational study. Explore (NY) 2006;2(2):109-14. PubMed
- Weiser, M., Gegenheimer, L. H., and Klein, P. A randomized equivalence trial comparing the efficacy and safety of Luffa comp.-Heel nasal spray with cromolyn sodium spray in the treatment of seasonal allergic rhinitis. Forsch Komplementarmed 1999;6(3):142- PubMed
- FDA OTC ingredients list, April 2010. Available at: www.fda.gov/downloads/AboutFDA/CentersOffices/CDER/UCM135691.pdf (accessed 2/7/15).
- Leyden, J. J., McGinley, K. J., Mills, O. H., Kyriakopoulos, A. A., and Kligman, A. M. Effects of sulfur and salicylic acid in a shampoo base in the treatment of dandruff: a double-blind study using corneocyte counts and clinical grading. Cutis 1987;39(6)
- Trumbore, M. W., Goldstein, J. A., and Gurge, R. M. Treatment of papulopustular rosacea with sodium sulfacetamide 10%/sulfur 5% emollient foam. J Drugs Dermatol 2009;8(3):299-304.
- Pelle, M. T., Crawford, G. H., and James, W. D. Rosacea: II. Therapy. J Am Acad Dermatol 2004;51:499-512.
- Blom I, Hornmark AM. Topical treatment with sulfur 10 per cent for rosacea. Acta Derm Venereol 1984;64:358-9. DOI
- Gupta, A. K. and Nicol, K. The use of sulfur in dermatology. J Drugs Dermatol 2004;3(4):427-31.
- Akhavan, A. and Bershad, S. Topical acne drugs: review of clinical properties, systemic exposure, and safety. Am J Clin Dermatol 2003;4(7):473-92.
- Wilkinson RD, Adam JE, Murray JJ, Craig GE. Benzoyl peroxide and sulfur: foundation for acne management. Can Med Assoc J 1966;95(1):28-9.
- Food and Drug Administration. Classification of benzoyl peroxide as safe and effective and revision of labeling to drug facts format; topical acne drug products for over-the-counter human use; final rule. Federal Register 2010;75(42):9767-77.
- Lin, A. N., Reimer, R. J., and Carter, D. M. Sulfur revisited. J Am Acad Dermatol 1988;18(3):553-8.
- Goszcz, A., Kostka-Trabka, E., Grodzinska, L., et al. [The effect of treatment with sulphur water from the spring in Wieslaw in Busko-Solec on levels of lipids, the fibrinolytic system and thrombogenic platelet function in patients with arteriosclerosis].
- Contoli M, Gnesini G, Forini G, et al. Reducing agents decrease the oxidative burst and improve clinical outcomes in COPD patients: a randomised controlled trial on the effects of sulphurous thermal water inhalation. ScientificWorldJournal. 2013 Dec 23;20 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.
Taking Sulfur and Glycerol Phenylbutyrate Together: Common Questions
Is it safe to take Sulfur with Glycerol Phenylbutyrate?
Do Sulfur and Glycerol Phenylbutyrate have any of the same side effects?
Should I take Sulfur and Glycerol Phenylbutyrate at the same time of day?
Does Glycerol Phenylbutyrate interact with any supplements?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
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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.