Drug & supplement interaction

Ribose + Fenfluramine

Fenfluramine brand name: Pondimin.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Ribose and Fenfluramine 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

Ribose and Fenfluramine

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 Fenfluramine and Ribose 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.

Ribose safety at a glance

Ribose overall Use caution Often well tolerated short-term, but it can lower blood sugar and long-term safety is not well studied.
Pregnancy Avoid There is not enough safety information, so it is best avoided during pregnancy.
Breastfeeding Avoid There is not enough safety information, so it is best avoided while breastfeeding.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Fenfluramine and Ribose? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Fenfluramine

Interactions in our licensed database are recorded against drug classes, not just single drug names. Fenfluramine is filed under 2 classifications — cytochrome p450 2d6 (cyp2d6) substrates, oral drugs. Ribose has documented interactions with 2 drug classes — the most serious being antidiabetes drugs (moderate) and insulin (moderate) — and none of Fenfluramine’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

Ribose Does Interact With Other Medications

Ribose has 86 moderate known drug interactions in our database — Fenfluramine 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 Ribose

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

What to actually watch for

No Interaction Found — But Data Suggests Ribose and Fenfluramine 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.

  • Diarrhea Additional detail

    Ribose

    “Orally, ribose can cause diarrhea, gastrointestinal discomfort, and nausea. In one study, lowering the dose of ribose resolved the nausea.”

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

    4 sources cited
    1. 5664. Pliml W, von Arnim T, Stalein A, et al. Effects of ribose on excercise-induced ischaemia in stable coronary artery disease. Lancet 1992;340:507-10.
    2. 5676. Gross M, Reiter S, Zollner N. Metabolism of D-ribose administered continuously to healthy persons and to patients with myoadenylate deaminase deficiency. Klin Wochenschr 1989;67:1205-13. PubMed
    3. 15218. Teitelbaum JE, Johnson C, St Cyr J. The use of D-ribose in chronic fatigue syndrome and fibromyalgia: a pilot study. J Altern Complement Med 2006;12:857-62. PubMed
    4. 92891. Thompson J, Neutel J, Homer K, Tempero K, Shah A, Khankari R. Evaluation of D-ribose pharmacokinetics, dose proportionality, food effect, and pharmacodynamics after oral solution administration in healthy male and female subjects. J Clin Pharmacol 2014;54 PubMed

    Fenfluramine

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

  • Headache Additional detail

    Ribose

    “Orally, ribose can cause headache. It has also been reported to cause a hyperanxious feeling, lightheadedness, increased appetite, and mild anxiety. In one study, lowering the dose of ribose resolved the feeling of anxiety.”

    Ribose · Natural Medicines adverse-effect record, reported in anxiety.

    3 sources cited
    1. 5664. Pliml W, von Arnim T, Stalein A, et al. Effects of ribose on excercise-induced ischaemia in stable coronary artery disease. Lancet 1992;340:507-10.
    2. 92891. Thompson J, Neutel J, Homer K, Tempero K, Shah A, Khankari R. Evaluation of D-ribose pharmacokinetics, dose proportionality, food effect, and pharmacodynamics after oral solution administration in healthy male and female subjects. J Clin Pharmacol 2014;54 PubMed
    3. 15218. Teitelbaum JE, Johnson C, St Cyr J. The use of D-ribose in chronic fatigue syndrome and fibromyalgia: a pilot study. J Altern Complement Med 2006;12:857-62. PubMed

    Fenfluramine

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

Reported for Ribose but not commonly for Fenfluramine: stomach upset, increased appetite, dizziness and low blood sugar.

Effects for Fenfluramine come from the ADVERSE REACTIONS section of its FDA label; effects for Ribose come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 4,666 voluntary FDA FAERS reports for Fenfluramine 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.

Overlapping uses

What Fenfluramine Is Prescribed For, and What Ribose Has Been Studied For

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

Fenfluramine is prescribed for: Fintepla (fenfluramine oral solution) is approved to treat seizures associated with Dravet syndrome (DS) and Lennox-Gastaut syndrome (LGS) in patients 2 years of age and older. It is used alongside other antiseizure medications. Both conditions are severe, often hard-to-control forms of epilepsy that typically begin in childhood. Fintepla is available only through a restricted program called the Fintepla REMS because of serious heart-related risks.

Ribose has been studied for:

  • Seizures studied, not established Ribose has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Ribose for seizures

    Although there is interest in using oral ribose for seizures, there is insufficient reliable information about the clinical effects of ribose for this condition.

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 Fenfluramine on your own; if you are taking Ribose for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

Everything else you take

See Every Supplement That Interacts With Fenfluramine

This page covers Ribose only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Fenfluramine page lists 77 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), 1,3-dmaa (moderate), Acacia Rigidula (moderate), Active Hexose Correlated Compound (ahcc) (moderate) and Ayahuasca (moderate).

By severity: 1 major · 56 moderate · 20 minor.

From our pharmacist’s overview on the Fenfluramine page

“Activated charcoal is the single major-rated risk here, and it earns that rating by soaking up fenfluramine (Pondimin) in the gut so that less of each dose ever reaches your blood. Fenfluramine is a serotonin-acting appetite suppressant, and a drug like that losing potency unpredictably is not a small thing, so I would treat this list…”

Reviewed by 2 · Jul 18, 2026

Open the Fenfluramine interaction page

One more smart check

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

We hold 543 real supplement products containing Ribose, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Ribose. Even though Ribose itself has no known interaction with Fenfluramine, 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 Ribose and Fenfluramine 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 Ribose
Top 25%

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

29 days ago today
Medication Fenfluramine
Steady interest

#1,564 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 Ribose reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Ribose and Fenfluramine 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 Ribose

What is Ribose?

  • Energy and fatigue
  • Athletic performance and recovery
  • Fibromyalgia symptoms
  • Chronic fatigue
  • Heart-related (cardiac) conditions

Ribose (D-ribose) is a simple sugar your body makes naturally and uses to build energy molecules like ATP. Some people take it for fatigue, fibromyalgia, exercise recovery, or heart conditions, but solid human evidence is limited and mostly small or preliminary. It is generally well tolerated in short-term use, but talk to your pharmacist or doctor before trying it, especially if you have diabetes.

Not applicable (a naturally occurring simple sugar) · Powder, capsules, tablets, drink mixes

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

Ribose: dosing

There is no official standardized dose of ribose, and the amounts used in studies have varied widely depending on the goal. Because of this, it is best to follow the directions on the product label.To lower the chance of stomach upset or low blood sugar, some people take it with food and start with a smaller amount.

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

Read the full Ribose monograph & all interactions
Medication

About Fenfluramine

What Is Fenfluramine Used For?

Brand name: Pondimin

Fintepla (fenfluramine oral solution) is approved to treat seizures associated with Dravet syndrome (DS) and Lennox-Gastaut syndrome (LGS) in patients 2 years of age and older. It is used alongside other antiseizure medications.

Both conditions are severe, often hard-to-control forms of epilepsy that typically begin in childhood. Fintepla is available only through a restricted program called the Fintepla REMS because of serious heart-related risks.

Most-Reported Side Effects for Fenfluramine

From FAERS, the FDA’s public side-effect reporting system (4,666 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Seizure 2,042 reports
Tricuspid valve incompetence 580 reports
Decreased appetite 529 reports
Somnolence 454 reports
Weight decreased 431 reports
See full Fenfluramine drug information
Keep checking

Other Drugs & Ribose

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

0Major
86Moderate
0Minor
2,743No known interaction
Moderate

86 interactions

Showing 60 of 86 moderate interactions — see all 86 on the Ribose page.

No interaction 2,743 drugs checked — show the list
Evidence & sources

Ribose References

The 8 references that drive our Ribose 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. Segal S, Foley J. The metabolism of D-ribose in man. J Clin Invest 1958;37:719-35. PubMed
  2. Perlmutter NS, Wilson RA, Angello DA, et al. Ribose facilitates thallium-201 redistribution in patients with coronary artery disease. J Nucl Med 1991;32:193-200.
  3. Hegewald MG, Palac RT, Angello DA, et al. Ribose infusion accelerates thallium redistribution with early imaging compared with late 24-hour imaging without ribose. J Am Coll Cardiol 1991;18:1671-81. PubMed
  4. Pliml W, von Arnim T, Stalein A, et al. Effects of ribose on excercise-induced ischaemia in stable coronary artery disease. Lancet 1992;340:507-10.
  5. Burke ER. D-Ribose What You Need To Know. Garden City Park, NY: Avery Publishing Group 1999;1-43.
  6. Gross M, Reiter S, Zollner N. Metabolism of D-ribose administered continuously to healthy persons and to patients with myoadenylate deaminase deficiency. Klin Wochenschr 1989;67:1205-13. PubMed
  7. Teitelbaum JE, Johnson C, St Cyr J. The use of D-ribose in chronic fatigue syndrome and fibromyalgia: a pilot study. J Altern Complement Med 2006;12:857-62. PubMed
  8. Thompson J, Neutel J, Homer K, Tempero K, Shah A, Khankari R. Evaluation of D-ribose pharmacokinetics, dose proportionality, food effect, and pharmacodynamics after oral solution administration in healthy male and female subjects. J Clin Pharmacol 2014;54 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 Ribose and Fenfluramine Together: Common Questions

Is it safe to take Ribose with Fenfluramine?
We do not list a known interaction between Ribose and Fenfluramine. 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 Ribose and Fenfluramine 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 Ribose and Fenfluramine 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 Ribose in each. That is a conversation for your prescriber, especially if Fenfluramine is being adjusted to a target.
How was the Ribose and Fenfluramine combination checked?
Interactions in our licensed database are recorded against drug classes. Fenfluramine is filed under 2 classifications, and Ribose has documented interactions with 2 drug classes — none of Fenfluramine'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 Ribose interact with any other medications?
Yes. Ribose has 86 documented drug interactions in our database — Fenfluramine 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 Fenfluramine interact with any supplements?
Yes. Fenfluramine has documented interactions with 77 supplements in our database — Ribose is not one of them. The Fenfluramine interaction page linked on this page lists every one, ranked by severity.

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.