Drug & supplement interaction

Weight Watchers Diet + Lansoprazole

Lansoprazole brand name: Prevacid.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Weight Watchers Diet and Lansoprazole 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.

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Interaction report

Weight Watchers Diet and Lansoprazole

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

Weight Watchers 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.

Weight Watchers Diet safety at a glance

Weight Watchers Di... overall Use caution Generally safe for most healthy adults, but check with a clinician if you have health conditions or take medications.
Pregnancy Use caution Weight loss is usually not advised during pregnancy; speak with your doctor about appropriate nutrition.
Breastfeeding Use caution Calorie restriction may affect milk supply, so discuss any diet plan with your healthcare provider first.

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

Still wondering about combining Lansoprazole and Weight Watchers Diet? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Lansoprazole

Interactions in our licensed database are recorded against drug classes, not just single drug names. Lansoprazole is filed under 5 classifications — including proton pump inhibitors (ppis), cytochrome p450 1a2 (cyp1a2) inducers, cytochrome p450 2c19 (cyp2c19) substrates. Weight Watchers Diet has documented interactions with 1 drug class — the most serious being antidiabetes drugs (moderate) — and none of Lansoprazole’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

Weight Watchers Diet Does Interact With Other Medications

Weight Watchers Diet has 86 moderate known drug interactions in our database — Lansoprazole 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 Weight Watchers Diet

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

What to actually watch for

What Lansoprazole’s Own FDA Label Lists

This is not an interaction — none of it involves Weight Watchers Diet. These are the most notable effects listed in the ADVERSE REACTIONS section of Lansoprazole’s own FDA label, for the medication by itself. Knowing the drug’s own list makes it easier to work out the likely cause if something new turns up while you follow Weight Watchers Diet and take the medicine. 10 of them are worth acting on rather than waiting out — marked below.

  • Kidney problems Worth acting on mentioned in 42.3% of FDA reports for Lansoprazole
  • Loss of vision Worth acting on
  • Low magnesium Worth acting on
  • A change in thyroid levels Worth acting on
  • Hearing loss Worth acting on
  • A stroke or mini-stroke Worth acting on
  • Bone thinning Worth acting on
  • Pain or burning when passing urine Worth acting on
  • Memory problems Worth acting on
  • Dehydration Worth acting on

Showing the 10 most notable of 89 label-listed effects — ranked by how unusual each one is across medicines generally, with serious effects weighted up.

From the ADVERSE REACTIONS section of the FDA label for Lansoprazole. Read the label on DailyMed › Where a percentage is shown, it is the share of 177,063 voluntary FDA FAERS reports for Lansoprazole that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Weight Watchers Diet’s licensed record lists no adverse effects our clinical vocabulary could match, so there is no Weight Watchers Diet side to compare — that is a limit of the record, not a statement that Weight Watchers Diet has no side effects.

From our Q&A

Questions About Weight Watchers Diet or Lansoprazole

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

This page covers Weight Watchers Diet only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Lansoprazole page lists 153 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), St. John's Wort (major), Acacia Rigidula (moderate) and Adrafinil (moderate).

By severity: 3 major · 101 moderate · 49 minor.

From our pharmacist’s overview on the Lansoprazole page

“Heartburn and reflux send plenty of people toward both lansoprazole (Prevacid) and the supplement aisle, and that pairing calls for genuine care, since three of the 153 ingredients on file here carry major-rated interactions. Most of the list works through the liver enzymes that clear lansoprazole, either slowing them down (grapefruit,…”

Reviewed by 2 · Jul 18, 2026

Open the Lansoprazole interaction page

How much people look this up

Where Weight Watchers Diet and Lansoprazole 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 Weight Watchers Diet
Steady interest

#1,087 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Lansoprazole
Steady interest

#1,699 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 Weight Watchers Diet reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Weight Watchers Diet and Lansoprazole records this page draws on were last updated June 22, 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 Weight Watchers Diet

What is Weight Watchers Diet?

  • Weight loss
  • Weight maintenance
  • Building healthier eating habits
  • Behavioral support for diet change
  • General wellness and lifestyle improvement

Weight Watchers (now called WW) is a commercial weight-loss program built around a points system, food tracking, and group or online support rather than a pill or herbal product. Research generally shows it can help people lose a modest amount of weight and keep some of it off, especially when combined with regular activity. Talk with your doctor or pharmacist before starting any weight-loss plan, particularly if you have a medical condition.

Not applicable (this is a commercial weight-management program, not a plant or supplement) · Structured eating plan with a points-based food system, app, group or online support, and coaching

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

Weight Watchers Diet: dosing

There is no pill or standardized dose for Weight Watchers, since it is a behavioral eating program. Instead, you follow the program's points budget and tracking system as set up in the app or plan you select.The right calorie or points target depends on your age, sex, weight, activity level, and goals, and the program personalizes this for you.

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

Read the full Weight Watchers Diet monograph & all interactions
Medication

About Lansoprazole

What Is Lansoprazole Used For?

Brand name: Prevacid

Lansoprazole is prescribed for a range of conditions where excess stomach acid is the problem. It treats active stomach and duodenal ulcers (sores in the stomach or upper small intestine), helps heal ulcers caused by NSAID pain relievers, and can reduce the risk of those ulcers coming back.

It's also used for gastroesophageal reflux disease (GERD), erosive esophagitis (acid damage to the esophagus), and rare conditions where the stomach makes far too much acid — like Zollinger-Ellison syndrome. When combined with antibiotics, it helps wipe out H. pylori bacteria that cause recurring ulcers.

Most-Reported Side Effects for Lansoprazole

From FAERS, the FDA’s public side-effect reporting system (177,063 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Chronic kidney disease 32,791 reports
Acute kidney injury 18,792 reports
Renal failure 13,844 reports
End stage renal disease 9,798 reports
Renal injury 9,520 reports
See full Lansoprazole drug information
Keep checking

Other Drugs & Weight Watchers Diet

Browse every other medication we’ve checked against Weight Watchers Diet — 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 Weight Watchers Diet page.

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

Weight Watchers Diet References

The 1 references that drive our Weight Watchers 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. O'Neil PM, Miller-Kovach K, Tuerk PW, et al. Randomized controlled trial of a nationally available weight control program tailored for adults with type 2 diabetes. Obesity (Silver Spring). 2016;24(11):2269-2277. 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 Weight Watchers Diet While Taking Lansoprazole: Common Questions

Is it safe to follow Weight Watchers Diet while taking Lansoprazole?
We do not list a known interaction between Weight Watchers Diet and Lansoprazole. 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.
How was the Weight Watchers Diet and Lansoprazole combination checked?
Interactions in our licensed database are recorded against drug classes. Lansoprazole is filed under 5 classifications, and Weight Watchers Diet has documented interactions with 1 drug class — none of Lansoprazole'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 Weight Watchers Diet interact with any other medications?
Yes. Weight Watchers Diet has 86 documented drug interactions in our database — Lansoprazole 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 Lansoprazole interact with any supplements?
Yes. Lansoprazole has documented interactions with 153 supplements in our database — Weight Watchers Diet is not one of them. The Lansoprazole 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 Lansoprazole and Weight Watchers 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.