Drug & supplement interaction

Weight Watchers Diet + Metformin XR

Metformin XR brand name: Glucophage XR.

Moderate Interaction
Medically reviewed by · Updated September 2026
The bottom line Moderate

Weight Watchers Diet has a moderate interaction with Metformin XR. Following the Weight Watchers diet while taking antidiabetes drugs may increase the risk of hypoglycemia.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceB
What do Severity, Likelihood & Evidence mean?
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Interaction report

Weight Watchers Diet and Metformin XR

Here is the interaction we found between these two, with the evidence behind it.

Moderate

ANTIDIABETES DRUGS

Why this applies to Metformin XR

Metformin XR falls under ANTIDIABETES DRUGS — the group Weight Watchers Diet interacts with.

Following the Weight Watchers diet while taking antidiabetes drugs may increase the risk of hypoglycemia.
Hypoglycemia has occurred in a small number of patients with type 2 diabetes who are taking antidiabetes medications and following the Weight Watchers Diet. Dose adjustments of antidiabetes medications might be necessary for some people.
Severity Moderate Likelihood Possible Evidence B

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the simple version: the Weight Watchers (WW) program doesn't react chemically with your Metformin XR. There's no enzyme or active ingredient at play here. Instead, the connection is about food and weight. When you eat fewer points and start dropping pounds, your body often needs less help controlling blood sugar, and your metformin may end up working a little stronger than before.

For most people on metformin alone, low blood sugar is uncommon, so the risk here is modest. Still, keep an eye out for shakiness, sweating, dizziness, or sudden hunger, especially if you skip meals. Don't change your dose on your own. Just give your doctor or pharmacist a heads-up that you're starting WW so they can check your numbers and adjust if needed.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  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

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Weight Watchers Diet Also Interacts With Other Medications

Weight Watchers Diet has 85 moderate known drug interactions in our database — the Metformin XR one above is one of them. If you take anything else, check it against the full list below.

Moderate 85 No known interaction 2,745 (incl. Metformin XR)
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.

Everything else you take

See Every Supplement That Interacts With Metformin XR

This page covers Weight Watchers Diet only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Metformin XR page lists 256 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Siberian Cocklebur (major), Acai (moderate), African Wild Potato (moderate) and Agaricus Mushroom (moderate).

By severity: 2 major · 215 moderate · 39 minor.

From our pharmacist’s overview on the Metformin XR page

“Siberian cocklebur stands alone at the top of this list; its seeds have caused severe low blood sugar in humans, and no one taking metformin XR (Glucophage XR) should use it. Almost everything else here, 239 of the 256 ingredients, affects blood sugar too, so this list earns real caution.”

Reviewed by 2 · Jul 18, 2026

Open the Metformin XR interaction page

How much people look this up

Where Weight Watchers Diet and Metformin XR 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

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

29 days ago today
Medication Metformin XR
Top 25%

#698 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.

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.

Read the full Weight Watchers Diet monograph & all interactions
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
85Moderate
0Minor
2,744No known interaction
85 Moderate 2,744 No interaction
Moderate

85 interactions

Showing 60 of 85 moderate interactions — see all 85 on the Weight Watchers Diet page.

No interaction 2,744 drugs checked — show the list

We also checked Weight Watchers Diet against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,744 medications checked with no known interaction — see the full Weight Watchers Diet list.

See the full Weight Watchers Diet interactions page
See every supplement checked against Metformin XR, ranked by severity
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

Keep exploring
Weight Watchers Diet monograph › Uses, safety, and every drug interaction in one place Metformin XR supplement interactions › Every supplement checked against Metformin XR, 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 Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Following Weight Watchers Diet While Taking Metformin XR: Common Questions

Can you follow Weight Watchers Diet while taking Metformin XR?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Weight Watchers Diet and Metformin XR interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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

Still Have a Question About Metformin XR 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.