Drug & supplement interaction

South Beach Diet + Ketoconazole

Ketoconazole brand name: Nizoral.

No Known Interaction
The bottom line No known interaction

We found no known interaction between South Beach Diet and Ketoconazole 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

South Beach Diet and Ketoconazole

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 Ketoconazole and South Beach Diet in our sources. This does not guarantee that the combination is completely free of risk — research on South Beach Diet alongside specific medications may be limited.

Worth understanding: our licensed dataset holds no drug-interaction record for South Beach Diet at all — not against Ketoconazole, 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.

South Beach Diet is an eating pattern rather than something you take. Ask your pharmacist or doctor before changing how you eat while on a prescribed medicine: some medicines are dosed around meals, and a change in diet can change how they work. 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.

South Beach Diet safety at a glance

South Beach Diet overall Use caution Generally safe for healthy adults, but the strict early phase may not suit everyone.
Pregnancy Use caution Restrictive or low-carb eating is not recommended in pregnancy without medical supervision.
Breastfeeding Use caution Nursing parents need adequate calories and nutrients, so avoid restrictive phases without guidance.

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

Still wondering about combining Ketoconazole and South Beach Diet? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

No Interaction Found — But Data Suggests South Beach Diet and Ketoconazole 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 following South Beach Diet while taking the medicine can make those effects more likely to turn up, and harder to pin on one or the other if they do.

  • Stomach pain / Vomiting / Nausea Additional detail

    South Beach Diet

    “One case of hyperglycemic ketoacidosis, with symptoms of nausea, vomiting, and abdominal pain, occurred in a non-diabetic 30-year-old patient that had implemented the South Beach diet for 3 weeks.”

    South Beach Diet · Natural Medicines adverse-effect record, reported in nausea and vomiting.

    1 source cited
    1. 90101. Chalasani S, Fischer J. South Beach Diet associated ketoacidosis: a case report. J Med Case Rep 2008;2:45. PubMed

    Ketoconazole

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

Effects for Ketoconazole come from the ADVERSE REACTIONS section of its FDA label; effects for South Beach Diet 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.

From our Q&A

Questions About South Beach Diet or Ketoconazole

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers South Beach Diet or Ketoconazole, 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 Ketoconazole

This page covers South Beach Diet only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Ketoconazole page lists 182 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Beer (major), Grapefruit (major), Siberian Cocklebur (major) and St. John's Wort (major).

By severity: 6 major · 135 moderate · 41 minor.

From our pharmacist’s overview on the Ketoconazole page

“Ketoconazole (Nizoral) is already hard on the liver, so treat its 182 interacting supplements with genuine care, starting with the six rated major. Most of the list runs through CYP3A4, the liver enzyme ketoconazole strongly blocks, so it can raise levels of over a hundred herbal ingredients, while grapefruit pushes ketoconazole itself…”

Reviewed by 2 · Jul 18, 2026

Open the Ketoconazole interaction page

How much people look this up

Where South Beach Diet and Ketoconazole 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 South Beach Diet
Steady interest

#1,331 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Ketoconazole
Steady interest

#1,667 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 South Beach Diet reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The South Beach Diet and Ketoconazole 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 .
Eating pattern

About South Beach Diet

What is South Beach Diet?

  • Weight loss
  • Blood sugar control
  • Reducing cravings for refined carbs
  • Improving cholesterol and heart health
  • General healthy eating

The South Beach Diet is a popular low-glycemic, higher-protein eating plan—not an herb or supplement. It can help some people lose weight and reduce refined-carb cravings, especially in the short term, but long-term success depends on sticking with healthy habits. Talk to your doctor or a dietitian before starting any restrictive diet, particularly if you have diabetes, kidney disease, or take medications.

Structured eating plan with three phases; books, prepackaged meals, and meal-delivery programs

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

South Beach Diet: dosing

There is no "dose" because the South Beach Diet is an eating plan, not a pill or supplement. Instead, you follow the structure of its phases and food lists as described in the official books or program materials.If you choose a prepackaged meal version, follow the program's serving guidance.

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

Read the full South Beach Diet monograph & all interactions
Medication

About Ketoconazole

What Is Ketoconazole Used For?

Brand name: Nizoral

Ketoconazole 2% shampoo and foam are used to treat tinea versicolor (also called pityriasis versicolor) — a fungal infection caused by Pityrosporum orbiculare (also known as Malassezia furfur), a yeast that naturally lives on the skin.

This infection creates light or dark patches, most often on the trunk, neck, arms, and upper thighs. Even after the fungus is cleared, those skin patches may take months to return to their normal color — that's normal, and depends on your skin type and sun exposure. Tinea versicolor can also come back, since the fungus lives on healthy skin even when there's no active infection.

Most-Reported Side Effects for Ketoconazole

From FAERS, the FDA’s public side-effect reporting system (0 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Pruritus 984 reports
Fatigue 975 reports
Nausea 873 reports
Rash 858 reports
Diarrhea 814 reports
See full Ketoconazole drug information
Keep checking

Other Drugs & South Beach Diet

Browse every other medication we’ve checked against South Beach Diet — 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
No interaction 2,829 drugs checked — show the list
Evidence & sources

South Beach Diet References

The 1 references that drive our South Beach Diet 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. Chalasani S, Fischer J. South Beach Diet associated ketoacidosis: a case report. J Med Case Rep 2008;2:45. 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

Following South Beach Diet While Taking Ketoconazole: Common Questions

Is it safe to follow South Beach Diet while taking Ketoconazole?
We do not list a known interaction between South Beach Diet and Ketoconazole. 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 South Beach Diet and Ketoconazole have any of the same side effects?
Yes — our sources link each of them separately to 3 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.
Does Ketoconazole interact with any supplements?
Yes. Ketoconazole has documented interactions with 182 supplements in our database — South Beach Diet is not one of them. The Ketoconazole 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 Ketoconazole and South Beach Diet?

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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.