Drug & supplement interaction

Ribose + Valganciclovir

Valganciclovir brand name: Valcyte.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Ribose and Valganciclovir 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 Valganciclovir 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.

Know someone taking this? Share
Interaction report

Ribose and Valganciclovir

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 Valganciclovir 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 Valganciclovir and Ribose? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Valganciclovir

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

  • Anxiety or restlessness / Dizziness 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

    Valganciclovir

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

  • Stomach upset / Diarrhea / Nausea 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

    Valganciclovir

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

  • Headache Additional detail

    Ribose

    Recorded for Ribose in the same Natural Medicines adverse-effect record shown under Stomach upset / Diarrhea / Nausea above.

    Valganciclovir

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

Reported for Ribose but not commonly for Valganciclovir: increased appetite and low blood sugar.

Effects for Valganciclovir come from the ADVERSE REACTIONS section of its FDA label; effects for Ribose 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.

How to take them

Some Valganciclovir Products Have a Food Rule — Ribose Should Not Break It

At least one FDA label for a product containing Valganciclovir says to take it with food. If you take Ribose on an empty stomach out of habit, keep them separate — and take Valganciclovir 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 Valganciclovir 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 DOSAGE AND ADMINISTRATION Adult Dosage ( 2.2 ) Treatment of CMV retinitis Induction: 900 mg (two 450 mg tablets) twice a day for 21 days Maintenance: 900 mg (two 450 mg tablets) once a day Prevention of CMV disease in heart or kidney-pancreas transplant patients 900 mg (two 450 mg tablets) once a day within 10 days of transplantation until 100 days post-transplantation Prevention of CMV disease

From the Dosage and Administration section of the FDA label we read for Valganciclovir — 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 Valganciclovir

This page covers Ribose only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Valganciclovir 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 Valganciclovir page

“Valganciclovir (Valcyte) treats cytomegalovirus, an infection that can blind or seriously sicken transplant recipients and others with weakened immunity, so each dose must be absorbed reliably. All 17 supplements on this list threaten exactly that, changing how much drug moves from gut to bloodstream, and that pairing deserves genuine…”

Reviewed by 2 · Jul 18, 2026

Open the Valganciclovir 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 Valganciclovir, 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 Valganciclovir 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%

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

29 days ago today
Medication Valganciclovir
Steady interest

#2,322 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 Valganciclovir 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 Valganciclovir

What Is Valganciclovir Used For?

Brand name: Valcyte

Valganciclovir treats CMV retinitis — a viral infection that can damage the retina and threaten vision — in adults with AIDS. It is also used to prevent CMV disease in adults who have had a kidney, heart, or kidney-pancreas transplant and are at high risk for infection.

In children, valganciclovir is used to prevent CMV disease in pediatric kidney transplant patients ages 4 months to 16 years, and in pediatric heart transplant patients ages 1 month to 16 years. The oral solution form is specifically indicated for these pediatric uses.

Most-Reported Side Effects for Valganciclovir

From FAERS, the FDA’s public side-effect reporting system (18,743 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Cytomegalovirus infection 1,821 reports
Neutropenia 1,147 reports
Fever 957 reports
Leukopenia 941 reports
Diarrhea 933 reports
See full Valganciclovir 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 Valganciclovir Together: Common Questions

Is it safe to take Ribose with Valganciclovir?
We do not list a known interaction between Ribose and Valganciclovir. 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 Valganciclovir have any of the same side effects?
Yes — our sources link each of them separately to 6 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 Ribose and Valganciclovir at the same time of day?
At least one FDA label for a product containing Valganciclovir says to take it with food. If you take Ribose on an empty stomach out of habit, keep them separate and take Valganciclovir with a meal where the label says to. Food instructions belong to the product rather than the ingredient — two Valganciclovir products can differ — so check the directions on your own box. This is about absorption, not an interaction.
How was the Ribose and Valganciclovir combination checked?
Interactions in our licensed database are recorded against drug classes. Valganciclovir is filed under 1 classification, and Ribose has documented interactions with 2 drug classes — none of Valganciclovir'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 — Valganciclovir 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 Valganciclovir interact with any supplements?
Yes. Valganciclovir has documented interactions with 17 supplements in our database — Ribose is not one of them. The Valganciclovir interaction page linked on this page lists every one, ranked by severity.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Valganciclovir and Ribose?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.