Drug & supplement interaction

Fasting + Liraglutide

Liraglutide brand name: Victoza.

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

Fasting has a moderate interaction with Liraglutide. Fasting might increase the risk of hypoglycemia if used with antidiabetes drugs.

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

Fasting and Liraglutide

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

Moderate

ANTIDIABETES DRUGS

Why this applies to Liraglutide

Liraglutide falls under ANTIDIABETES DRUGS — the group Fasting interacts with.

Fasting might increase the risk of hypoglycemia if used with antidiabetes drugs.
Hypoglycemic events have been reported during intermittent fasting, including in patients using antidiabetes drugs. The risk of having a hypoglycemic event is largest for patients taking insulin or sulfonylureas. The risk of hypoglycemic events seems to be lower for patients taking other antidiabetes drugs such as glucagon-like peptide-1 receptor agonist (GLP- 1RA), metformin, thiazolidinediones, dipeptidyl peptidase-4 inhibitors (DPP4 inhibitors), and sodium-glucose cotransporter-2 (SGLT2) inhibitors. Advise patients to monitor glucose levels closely. Dose or time adjustments may be necessary.
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: when you skip meals while using Victoza (liraglutide), your blood sugar can drop lower than usual. Fasting itself lowers blood sugar, and your medicine is also working to keep it down, so the two together can push your levels too low. Watch for shakiness, sweating, a fast heartbeat, confusion, or feeling lightheaded.

The good news is that liraglutide carries a lower hypoglycemia risk than insulin or sulfonylureas (like glipizide), so for most people on Victoza alone the chance is modest. The risk climbs if you also take one of those other medicines. Before starting any fasting routine, talk with your pharmacist or doctor, and keep checking your glucose so any adjustments can be made safely.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Carter S, Clifton PM, Keogh JB. Effect of intermittent compared with continuous energy restricted diet on glycemic control in patients with Type 2 diabetes: A randomized noninferiority trial. JAMA Netw Open. 2018;1(3):e180756. PubMed
  2. Cioffi I, Evangelista A, Ponzo V, et al. Intermittent versus continuous energy restriction on weight loss and cardiometabolic outcomes: a systematic review and meta-analysis of randomized controlled trials. J Transl Med. 2018;16(1):371. PubMed
  3. Chowdhury A, Khan H, Lasker SS, Chowdhury TA. Fasting outcomes in people with diabetes and chronic kidney disease in East London during Ramadan 2018: The East London diabetes in Ramadan survey. Diabetes Res Clin Pract. 2019;152:166-170. PubMed
  4. Grajower MM, Horne BD. Clinical management of intermittent fasting in patients with diabetes mellitus. Nutrients. 2019;11(4):873. PubMed
  5. Ibrahim M, Davies MJ, Ahmad E, et al. Recommendations for management of diabetes during Ramadan: update 2020, applying the principles of the ADA/EASD consensus. BMJ Open Diabetes Res Care. 2020;8(1):e001248. PubMed
  6. Wang X, Li Q, Liu Y, Jiang H, Chen W. Intermittent fasting versus continuous energy-restricted diet for patients with type 2 diabetes mellitus and metabolic syndrome for glycemic control: A systematic review and meta-analysis of randomized controlled tria

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

Fasting Also Interacts With Other Medications

Fasting has 2 major, 205 moderate known drug interactions in our database — the Liraglutide one above is one of them. If you take anything else, check it against the full list below.

Major 2 Moderate 205 No known interaction 2,623 (incl. Liraglutide)
Taking anything else?

Check Another of Your Medications Against Fasting

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

Everything else you take

See Every Supplement That Interacts With Liraglutide

This page covers Fasting only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Liraglutide page lists 239 supplements it has a documented interaction with, worst first, each one explained.

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

By severity: 1 major · 208 moderate · 30 minor.

From our pharmacist’s overview on the Liraglutide page

“If you take liraglutide (Victoza), the ingredient to know first is Siberian cocklebur, the only major-rated interaction of the 239 on this page. Its seeds have caused severe hypoglycemia in people, dangerously low blood sugar, and liraglutide already pushes glucose down.”

Reviewed by 2 · Jul 18, 2026

Open the Liraglutide interaction page

How much people look this up

Where Fasting and Liraglutide 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 Fasting
Top half

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

29 days ago today
Medication Liraglutide
Steady interest

#1,774 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 Fasting

What is Fasting?

  • Weight loss
  • Blood sugar control
  • Heart health
  • Religious or spiritual practice
  • General wellness and longevity

Fasting means voluntarily going without food (and sometimes drink) for set periods. Some research suggests it may help with weight loss and blood sugar in certain people, but results vary and quality of evidence is mixed. It is not safe for everyone, so check with your doctor or pharmacist before starting—especially if you take medication or have a health condition.

Read the full Fasting monograph & all interactions
Medication

About Liraglutide Injection

What Is Liraglutide Injection Used For?

Brand name: Victoza

Saxenda is used alongside a reduced-calorie diet and increased physical activity for chronic weight management. It is approved for adults with a BMI of 30 or higher, or a BMI of 27 or higher if they also have at least one weight-related condition such as high blood pressure, type 2 diabetes, or dyslipidemia (abnormal cholesterol or fat levels). It is also approved for adolescents aged 12 and older who weigh more than 60 kg and meet certain BMI thresholds for obesity.

Saxenda should not be used together with other liraglutide-containing products or any other GLP-1 receptor agonist. Its safety and effectiveness in combination with other prescription or over-the-counter weight-loss products have not been established.

See full Liraglutide Injection drug information
Keep checking

Other Drugs & Fasting

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

2Major
205Moderate
0Minor
2,622No known interaction
2 Major 205 Moderate 2,622 No interaction
Major

2 interactions

Moderate

205 interactions

Showing 60 of 205 moderate interactions — see all 205 on the Fasting page.

No interaction 2,622 drugs checked — show the list

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

Showing the 60 most looked-up of 2,622 medications checked with no known interaction — see the full Fasting list.

See the full Fasting interactions page
See every supplement checked against Liraglutide, 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
Fasting monograph › Uses, safety, and every drug interaction in one place Liraglutide supplement interactions › Every supplement checked against Liraglutide, ranked by severity Liraglutide Injection drug information › The full plain-English guide to this medication 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 Fasting While Taking Liraglutide: Common Questions

Can you follow Fasting while taking Liraglutide?
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 Fasting and Liraglutide 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 Liraglutide and Fasting?

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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.