Drug & supplement interaction

Ornithine Ketoglutarate (okg) + Diltiazem

Diltiazem brand names: Cardizem, Cardizem SR, Diltiaz SR, Cardizem CD, Tiazac, and others.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Oct 4, 2026
The bottom line No known interaction

We found no known interaction between Ornithine Ketoglutarate (okg) and Diltiazem 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

Ornithine Ketoglutarate (okg) and Diltiazem

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 Diltiazem and Ornithine Ketoglutarate (okg) 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 Ornithine Ketoglutarate (okg) at all — not against Diltiazem, 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.

Ornithine Ketoglutarate (okg) safety at a glance

Ornithine Ketoglut... overall Use caution Generally well tolerated in short-term clinical studies, but long-term safety as a daily supplement is not well established.
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 Diltiazem and Ornithine Ketoglutarate (okg)? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

No Interaction Found — But Data Suggests Ornithine Ketoglutarate (okg) and Diltiazem 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.

  • Bloating or gas / Diarrhea / Nausea / Vomiting reported in 7.1% of FDA reports for Diltiazem Additional detail

    Ornithine Ketoglutarate (okg)

    “Orally, the most common adverse effects are gastrointestinal in nature, including abdominal pain, bloating, diarrhea, nausea, and vomiting.”

    Ornithine Ketoglutarate (okg) · Natural Medicines adverse-effect record, reported in diarrhea.

    3 sources cited
    1. 67449. Karsegard, V. L., Raguso, C. A., Genton, L., Hirschel, B., and Pichard, C. L-ornithine alpha-ketoglutarate in HIV infection: effects on muscle, gastrointestinal, and immune functions. Nutrition 2004;20(6):515-520.
    2. 67453. Meaume, S., Kerihuel, J. C., Constans, T., Teot, L., Lerebours, E., Kern, J., and Bourdel, Marchasson, I. Efficacy and safety of ornithine alpha-ketoglutarate in heel pressure ulcers in elderly patients: results of a randomized controlled trial. J.Nutr.H PubMed
    3. 67466. Brocker, P., Vellas, B., Albarede, J. L., and Poynard, T. A two-centre, randomized, double-blind trial of ornithine oxoglutarate in 194 elderly, ambulatory, convalescent subjects. Age Ageing 1994;23(4):303-306. PubMed

    Diltiazem

    Listed in the ADVERSE REACTIONS section of the FDA label for Diltiazem, and in voluntary FDA adverse-event reports. Read the label on DailyMed ›

  • Itching Additional detail

    Ornithine Ketoglutarate (okg)

    “Orally, pruritus has occurred rarely.”

    Ornithine Ketoglutarate (okg) · Natural Medicines adverse-effect record, reported in pruritus.

    1 source cited
    1. 67466. Brocker, P., Vellas, B., Albarede, J. L., and Poynard, T. A two-centre, randomized, double-blind trial of ornithine oxoglutarate in 194 elderly, ambulatory, convalescent subjects. Age Ageing 1994;23(4):303-306. PubMed

    Diltiazem

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

Reported for Ornithine Ketoglutarate (okg) but not commonly for Diltiazem: stomach pain.

Effects for Diltiazem come from the ADVERSE REACTIONS section of its FDA label; effects for Ornithine Ketoglutarate (okg) come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 34,400 voluntary FDA FAERS reports for Diltiazem 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 Diltiazem Is Prescribed For, and What Ornithine Ketoglutarate (okg) Has Been Studied For

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

Diltiazem is prescribed for: Oral extended-release diltiazem (capsules and tablets) treats high blood pressure (hypertension). It is also used for chronic stable angina, which is chest pain from the heart working harder than its blood supply allows. It can be used alone or with other blood pressure medicines. Some extended-release capsule products, such as Cartia, Cartia Xt and certain generic diltiazem capsules, are also approved for angina due to coronary artery spasm.

Read the rest of what Diltiazem is prescribed for

The intravenous (IV) injection is a different use: it gives temporary control of a rapid heart rate in atrial fibrillation or atrial flutter, and rapidly converts paroxysmal supraventricular tachycardia (PSVT) to normal rhythm.

Ornithine Ketoglutarate (okg) has been studied for:

  • Stroke studied, not established Ornithine Ketoglutarate (okg) has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Ornithine Ketoglutarate (okg) for stroke

    It is unclear if oral ornithine ketoglutarate is beneficial in patients with a recent stroke.

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 Diltiazem on your own; if you are taking Ornithine Ketoglutarate (okg) for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

From our Q&A

Questions About Ornithine Ketoglutarate (okg) or Diltiazem

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Ornithine Ketoglutarate (okg) or Diltiazem, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Diltiazem

This page covers Ornithine Ketoglutarate (okg) only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Diltiazem page lists 260 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), American Mistletoe (major), Coleus (major) and Grapefruit (major).

By severity: 7 major · 214 moderate · 39 minor.

From our pharmacist’s overview on the Diltiazem page

“Someone on diltiazem (Cardizem, Tiazac) is usually managing blood pressure, angina, or a fast heart rhythm, so this list deserves genuine care. Seven of the 260 ingredients on file carry a major rating, and two of those are things people actually buy: grapefruit, which blocks the enzyme that clears diltiazem and can push its blood leve…”

Reviewed by 2 · Jul 18, 2026

Open the Diltiazem interaction page

How much people look this up

Where Ornithine Ketoglutarate (okg) and Diltiazem 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 Ornithine Ketoglutarate (okg)
Steady interest

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

29 days ago today
Medication Diltiazem
Top 25%

#345 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 Ornithine Ketoglutarate (okg) reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified October 4, 2026. The Ornithine Ketoglutarate (okg) and Diltiazem 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 Ornithine Ketoglutarate (okg)

What is Ornithine Ketoglutarate (okg)?

  • Wound healing and recovery from injury
  • Muscle preservation in older or hospitalized adults
  • Sports and athletic performance
  • Recovery from burns or surgery
  • Support during malnutrition or critical illness

Ornithine ketoglutarate (OKG) is a compound made by combining the amino acids ornithine and alpha-ketoglutarate, and it has mainly been studied in hospital settings for wound healing, burns, and malnutrition. Evidence for everyday use, such as sports performance, is limited and not convincing. Talk to your pharmacist or doctor before using it, especially if you have a health condition.

Not applicable (a synthesized amino acid salt) · Powder, capsules, tablets, and as part of clinical nutrition formulas

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

Ornithine Ketoglutarate (okg): dosing

There is no official standardized dose of OKG for general use. In clinical studies, doses were chosen by researchers and given to specific patient groups, often under medical care.If you use a supplement, follow the directions on the product label and do not assume more is better.

From our Ornithine Ketoglutarate (okg) monograph — the full record covers uses, side effects and every documented interaction.

Read the full Ornithine Ketoglutarate (okg) monograph & all interactions
Medication

About Diltiazem

What Is Diltiazem Used For?

Brand names: Cardizem, Cardizem SR, Diltiaz SR, Cardizem CD, Tiazac, Diltiaz XT, Diltiaz CD, Dilacor, Diltiaz, Cardizem LA, Dilacor XR, Cartia XT, Tiamate, Adizem-SR, Adizem-XL, Angitil SR, Angitil XL, Calcicard CR, Dilcardia SR, Dilzem SR, Dilzem XL, Slozem, Tildiem LA, Tildiem Retard, Viazem XL, Zemtard 120XL, Zemtard 180XL, Zemtard 240XL, Zemtard 300XL

Oral extended-release diltiazem (capsules and tablets) treats high blood pressure (hypertension). It is also used for chronic stable angina, which is chest pain from the heart working harder than its blood supply allows. It can be used alone or with other blood pressure medicines.

Some extended-release capsule products, such as Cartia, Cartia Xt and certain generic diltiazem capsules, are also approved for angina due to coronary artery spasm. The intravenous (IV) injection is a different use: it gives temporary control of a rapid heart rate in atrial fibrillation or atrial flutter, and rapidly converts paroxysmal supraventricular tachycardia (PSVT) to normal rhythm.

Most-Reported Side Effects for Diltiazem

From FAERS, the FDA’s public side-effect reporting system (34,219 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Dyspnea 3,296 reports
Fatigue 2,726 reports
Nausea 2,441 reports
Dizziness 2,163 reports
Diarrhea 2,106 reports
See full Diltiazem drug information
Keep checking

Other Drugs & Ornithine Ketoglutarate (okg)

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

0Major
0Moderate
0Minor
2,829No known interaction
2,829 No interaction
No interaction 2,829 drugs checked — show the list

We also checked Ornithine Ketoglutarate (okg) against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,829 medications checked with no known interaction — see the full Ornithine Ketoglutarate (okg) list.

See the full Ornithine Ketoglutarate (okg) interactions page
See every supplement checked against Diltiazem, ranked by severity
Evidence & sources

Ornithine Ketoglutarate (okg) References

The 3 references that drive our Ornithine Ketoglutarate (okg) 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. Karsegard, V. L., Raguso, C. A., Genton, L., Hirschel, B., and Pichard, C. L-ornithine alpha-ketoglutarate in HIV infection: effects on muscle, gastrointestinal, and immune functions. Nutrition 2004;20(6):515-520.
  2. Meaume, S., Kerihuel, J. C., Constans, T., Teot, L., Lerebours, E., Kern, J., and Bourdel, Marchasson, I. Efficacy and safety of ornithine alpha-ketoglutarate in heel pressure ulcers in elderly patients: results of a randomized controlled trial. J.Nutr.H PubMed
  3. Brocker, P., Vellas, B., Albarede, J. L., and Poynard, T. A two-centre, randomized, double-blind trial of ornithine oxoglutarate in 194 elderly, ambulatory, convalescent subjects. Age Ageing 1994;23(4):303-306. 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 Ornithine Ketoglutarate (okg) and Diltiazem Together: Common Questions

Is it safe to take Ornithine Ketoglutarate (okg) with Diltiazem?
We do not list a known interaction between Ornithine Ketoglutarate (okg) and Diltiazem. 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 Ornithine Ketoglutarate (okg) and Diltiazem have any of the same side effects?
Yes — our sources link each of them separately to 5 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 Ornithine Ketoglutarate (okg) and Diltiazem 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 Ornithine Ketoglutarate (okg) in each. That is a conversation for your prescriber, especially if Diltiazem is being adjusted to a target.
Does Diltiazem interact with any supplements?
Yes. Diltiazem has documented interactions with 260 supplements in our database — Ornithine Ketoglutarate (okg) is not one of them. The Diltiazem 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

Ornithine Ketoglutarate (okg) monograph Uses, safety profile, and every drug interaction in one place Diltiazem drug information The full plain-English guide to this medication Diltiazem supplement interactions Every supplement checked against Diltiazem, 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 3 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Diltiazem and Ornithine Ketoglutarate (okg)?

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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.