Drug & supplement interaction

Goji + Losartan Potassium

Losartan Potassium brand name: Cozaar.

Moderate Interaction
The bottom line Moderate

Losartan Potassium falls into 3 drug categories that Goji can interact with; the most serious is rated moderate. Theoretically, concomitant use of goji root bark, but not goji fruit, with antihypertensive drugs might have additive effects.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions3
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Goji and Losartan Potassium

These two interact in 3 distinct ways. Each one is explained separately below.

Why Are There 3 Interactions?

Goji interacts with whole categories of medication. Losartan Potassium falls into 3 of those categories, so it can interact with Goji in 3 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

ANTIHYPERTENSIVE DRUGS

1 of 3

Why this applies to Losartan Potassium

Losartan Potassium falls under ANTIHYPERTENSIVE DRUGS — the group Goji interacts with.

Theoretically, concomitant use of goji root bark, but not goji fruit, with antihypertensive drugs might have additive effects.
Animal and in vitro research suggest that goji root bark has hypotensive effects. However, goji fruit juice does not appear to reduce systolic or diastolic blood pressure in humans.
Severity Moderate Likelihood Possible Evidence D

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 is the practical takeaway with losartan (Cozaar): the concern on file is theoretical and comes from the root bark of the goji plant, not the berries themselves. In lab and animal studies, goji root bark seemed to lower blood pressure on its own. If that effect carried over to people, stacking it on top of a blood pressure medicine like losartan could push your numbers down too far, leaving you feeling dizzy, lightheaded, or tired, especially when standing up quickly.

That said, the goji fruit and its juice, which is what most people eat or drink, did not lower blood pressure in human studies. So enjoying goji berries as food is unlikely to be a problem. If you are considering a concentrated goji root supplement, check with your pharmacist or doctor first.

References
  1. Huang KC. The Pharmacology of Chinese Herbs. 2nd ed. Boca Raton, FL: CRC Press, LLC 1999.
  2. Amagase H, Nance DM. A randomized, double-blind, placebo-controlled, clinical study of the general effects of a standardized Lycium barbarum (goji) juice, GoChi. J Altern Complement Med 2008;14:403-12.
  3. Potterat O. Goji (Lycium barbarum and L. chinense): Phytochemistry, pharmacology and safety in the perspective of traditional uses and recent popularity. Planta Med 2010;76(1):7-19.
Moderate

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES

2 of 3

Losartan Potassium also falls under CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES.

Theoretically, goji berry might inhibit CYP2C9 and reduce metabolism of CYP2C9 substrates.
In vitro research shows that goji berry tincture and juice inhibit CYP2C9 enzymes. Additionally, multiple case reports suggest that goji berry concentrated tea and juice inhibit the metabolism of warfarin, a CYP2C9 substrate. Concomitant use with goji may decrease metabolism and increase levels of CYP2C9 substrates.
Severity Moderate Likelihood Possible Evidence D

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 something interesting about losartan: it actually relies on a liver enzyme called CYP2C9 to turn into its more active form. So losartan is partly a prodrug. Goji berry, in lab studies and a few warfarin case reports, seems to slow that same enzyme down. If goji blocks CYP2C9, your body may make less of the active drug, which could mean losartan works a little less well at controlling your blood pressure.

To be honest, this is mostly theoretical for losartan and based on weak evidence, so I wouldn't panic. Eating goji berries as food is very unlikely to cause trouble. Concentrated goji teas, juices, or supplements are the bigger question. If you use those regularly, just keep an eye on your blood pressure readings and check in with your pharmacist or doctor before changing anything.

References
  1. Lam AY, Elmer GW, Mohutsky MA. Possible interaction between warfarin and Lycium Barbarum. Ann Pharmacother 2001;35:1199-201.
  2. Guzmán CE, Guzmán-Moreno CG, Assad-Morell JL, Edgar Francisco Carrizales-Sepúlveda EF. Flecainide toxicity associated with the use of goji berries: a case report. Eur Heart J Case Rep. 2021;5(6):ytab204. PubMed
  3. Liu R, Tam TW, Mao J, et al. In vitro activity of Lycium barbarum (Goji) against major human phase I metabolism enzymes. Complement Integr Med. 2016;13(3):257-265.
Moderate

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

3 of 3

Losartan Potassium also falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES.

Theoretically, goji berry might inhibit CYP3A4 and reduce metabolism of CYP3A4 substrates.
In vitro research shows that goji berry juice inhibits CYP3A4 enzymes. Concomitant use with goji may decrease metabolism and increase levels of CYP3A4 substrates. However, this has not been reported in humans.
Severity Moderate Likelihood Possible Evidence D

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 something worth knowing about goji and losartan. Losartan is actually activated in your body by liver enzymes (mainly CYP2C9, with some help from CYP3A4) into its more powerful active form. Lab studies suggest goji might slow down CYP3A4. So in theory, blocking that pathway could shift how much active drug you end up with. The good news is this effect is quite small for losartan, and it has never been seen in real people, only in test-tube research.

If anything changed, you might notice your blood pressure running a bit higher or lower than usual, or feel lightheaded. Eating goji berries as food is very unlikely to matter. If you take concentrated goji supplements, just mention it to your pharmacist or doctor and keep an eye on your blood pressure.

References
  1. Liu R, Tam TW, Mao J, et al. In vitro activity of Lycium barbarum (Goji) against major human phase I metabolism enzymes. Complement Integr Med. 2016;13(3):257-265.

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

Goji Also Interacts With Other Medications

Goji has 2 major, 929 moderate, 68 minor known drug interactions in our database — the Losartan Potassium one above is among them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Goji

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

From our Q&A

Questions About Goji or Losartan Potassium

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Goji or Losartan Potassium, 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 Losartan Potassium

This page covers Goji only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Losartan Potassium page lists 253 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), Grapefruit (major) and St. John's Wort (major).

By severity: 6 major · 205 moderate · 42 minor.

From our pharmacist’s overview on the Losartan Potassium page

“Losartan potassium (Cozaar) treats high blood pressure, and this is a list to respect, because six of its 253 supplement interactions carry a major rating. Most entries do one of two things.”

Reviewed by 2 · Jul 18, 2026

Open the Losartan Potassium interaction page

One more smart check

Taking Goji as Part of a Dietary Supplement Product? Check It for Interactions

We hold 1,738 real supplement products containing Goji, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Goji. Your product may carry other ingredients that interact with Losartan Potassium too, on top of Goji — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Goji and Losartan Potassium 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 Goji
Top 10%

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

29 days ago today
Medication Losartan Potassium
Top 10

#6 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.

Supplement

About Goji

What is Goji?

Goji
  • General antioxidant support
  • Eye health
  • Immune support
  • Anti-aging and well-being
  • Blood sugar support

Goji berries are a nutritious fruit rich in antioxidants, vitamins, and plant polysaccharides, and they are safe for most people as a food. While they are popular for eye health, immune support, and general wellness, strong human evidence for most health claims is limited. Talk with your pharmacist or doctor before using concentrated goji supplements, especially if you take medications or are pregnant.

Read the full Goji monograph & all interactions
Medication

About Losartan

What Is Losartan Used For?

Brand name: Cozaar

Losartan tablets — available as branded Cozaar and several generic products — are used to treat high blood pressure (hypertension) in adults and children 6 years and older. Lowering blood pressure reduces the risk of strokes and heart attacks. Losartan tablets are also used to reduce the risk of stroke in people with high blood pressure who also have left ventricular hypertrophy (an enlarged left side of the heart). Note: evidence suggests this stroke-risk benefit may not apply to Black patients.

Losartan tablets are additionally approved to protect the kidneys in people with type 2 diabetes, high blood pressure, and signs of kidney damage (diabetic nephropathy). Arbli, the oral suspension form, shares these same approved uses.

See full Losartan drug information
Keep checking

Other Drugs & Goji

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

2Major
929Moderate
68Minor
1,830No known interaction
Major

2 interactions

Moderate

929 interactions

Showing 60 of 929 moderate interactions — see all 929 on the Goji page.

Minor

68 interactions

Showing 60 of 68 minor interactions — see all 68 on the Goji page.

No interaction 1,830 drugs checked — show the list
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

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Pharmacist Counseling Corner

Taking Goji and Losartan Potassium Together: Common Questions

Can you take Goji with Losartan Potassium?
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.
Why are there 3 interactions listed for Goji and Losartan Potassium?
Losartan Potassium belongs to more than one drug category, and Goji interacts with each of those categories a little differently. We list every one so nothing is missed — your overall risk is driven by the most serious of them.
How serious is the Goji and Losartan Potassium 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 Losartan Potassium and Goji?

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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.