Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

CranStat Extra Ingredients & Drug Interactions

by Vitanica

Capsule Category: Botanical
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

CranStat Extra is a dietary supplement by Vitanica with 6 active ingredients. Its ingredients are commonly taken for psoriasis (topical), eczema and other skin conditions, digestive upset.Based on those ingredients, 2,197 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Marshmallow, Oregon Grape, Uva Ursi leaf extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of CranStat Extra by Vitanica

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 6 of its 6 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

CranStat Extra contains six active ingredients chosen for urinary tract health. Oregon grape, marshmallow, cranberry concentrate, buchu leaf extract, uva ursi leaf extract, and pipsissewa are the working components.

The product is made up in a vegetarian capsule, which is the only inactive ingredient listed.

Does it work?

Moderate evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: healthy bladder and urinary tract support.
  • We looked for evidence on: Urinary tract infections (UTIs), Overactive bladder, Radiation-induced cystitis, Catheter-related infections, Kidney stones (nephrolithiasis), Urinary odor — and 3 related terms.
  • The strongest evidence on file: Cranberry is rated "Possibly Effective" for Urinary tract infections (UTIs) (Natural Medicines).
  • Also on file: Uva Ursi is rated "Possibly Ineffective" for Urinary tract infections (UTIs).
  • Also on file: Cranberry is rated "Insufficient Reliable Evidence To Rate" for Kidney stones (nephrolithiasis), Urinary odor, Overactive bladder, Catheter-related infections, and more.

The evidence we hold is limited and mixed. Cranberry concentrate is possibly effective for urinary tract infections (UTIs), while uva ursi leaf extract is rated as possibly ineffective for UTIs — making these two ingredients work against each other in that regard.

For the other conditions this product might address, the evidence in our data is insufficient to rate. Oregon grape is possibly effective for psoriasis but insufficient evidence exists for eczema.

Marshmallow, buchu leaf, and pipsissewa lack established effectiveness ratings in our data.

The evidence, ingredient by ingredient Oregon Grape Marshmallow Cranberry Buchu Uva Ursi Pipsissewa

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 4 of the 6 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 6 of 6.
  • General safety write-ups exist for 6 of 6.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Cranberry concentrate is likely safe during pregnancy and breastfeeding in normal food amounts, though concentrated supplement doses haven't been well studied — check with your provider first. Oregon grape is rated likely unsafe in pregnancy and while breastfeeding because berberine-containing plants are traditionally avoided and the compound may pass to infants.

Marshmallow, buchu leaf, and uva ursi are best avoided in pregnancy and breastfeeding due to insufficient safety data or traditional concerns. Uva ursi can cause diarrhea, nausea, stomach upset, and vomiting in low doses used short-term; at very high doses (20 grams or more of dried herb), it may cause serious effects including convulsions and delirium.

Pipsissewa may cause hydroquinone toxicity with chronic use, marked by ringing in the ears, vomiting, delirium, convulsions, and collapse.

Side effects, ingredient by ingredient Oregon Grape Marshmallow Cranberry Buchu Uva Ursi Pipsissewa

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 5 of the 6 matched ingredients can interact with medications — Buchu, Uva Ursi, Oregon Grape, Marshmallow, Cranberry.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; lithium.
  • For scale: 2,198 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking CranStat Extra, check with your pharmacist if you take blood thinners (anticoagulants or antiplatelet drugs like warfarin, aspirin, or clopidogrel) — Moderate risk of increased bleeding. Also double-check any blood pressure medication (antihypertensive drugs), diabetes medication, drugs metabolized through your liver (CYP3A4, CYP2C9, CYP2D6, or CYP2C19 substrates), lithium, or cholesterol medications like atorvastatin or nifedipine.

Marshmallow may also slow how your body absorbs other oral medications.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

CranStat Extra is designed for urinary tract support, but the evidence for most of its ingredients is limited. If you take any prescription medication — especially blood thinners, diabetes drugs, blood pressure pills, or cholesterol medications — you'll want to check them against this product before starting.

Talk with your pharmacist or doctor about whether it's right for you, and avoid it during pregnancy and breastfeeding.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 6 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated May 23, 2014.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about CranStat Extra, straight from the product label.

Brand Vitanica
Barcode (UPC) 708118020704
Net contents 60 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD May 23, 2014
DSLD ID 33429
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for CranStat Extra by Vitanica, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
2 Capsule(s)
Maximum serving Sizes:
2 Capsule(s)
Servings per container
30
UPC/BARCODE
708118020704
IngredientAmount% DV
Oregon Grape200 mg--
Marshmallow150 mg--
Cranberry concentrate150 mg--
Buchu leaf extract300 mg--
Uva Ursi leaf extract300 mg--
Pipsissewa300 mg--

Other ingredients: vegetarian capsule

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
General Statements

Formulated by Dr. Tori Hudson, a Naturopathic Physician specializing in women's natural health.

h {capsule} Actual Size

URINARY TRACT SUPPORT FORMULATED BY DR. TORI HUDSON

Brand IP Statement(s)

CranStat Extra(TM) is an herbal formula combining science and traditional herbal knowledge to promote and support healthy bladder and urinary tract tissue.

Suggested/Recommended/Usage/Directions

Suggested Use: For short-term management, use as directed by your healthcare practitioner. Two (2) capsules once per day may be taken for maintenance support.

Precautions

Avoid use of this product during pregnancy and nursing.

Tamper resistant: please do not use if safety seal is broken or missing.

Keep in a cool, dry place out of reach of children.

Formulation

This product contains no: preservatives, binders, artificial colorings or flavorings, sugars, starch, lactose, salt, corn, wheat, gluten, soybeans, milk derivatives, eggs, peanuts, tree nuts, fish or shellfish.

CranStat Extra(R) is suitable for vegetarians and vegans.

Storage

Keep in a cool, dry place out of reach of children.

FDA Statement of Identity

Dietary Supplement

FDA Disclaimer Statement

This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

See for yourself

CranStat Extra by Vitanica label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

What’s inside

The Ingredients in CranStat Extra by Vitanica

These are the 6 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule Servings per container30 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Oregon Grape

Interacts with
1,218 drugs
200 mg per serving

Oregon grape is a shrub whose root contains berberine and related compounds. The strongest (though still modest) evidence is for topical creams that m...

Oregon Grape monograph & interactions

Marshmallow

Interacts with
2,040 drugs
150 mg per serving

Marshmallow root is a traditional herb rich in soothing, gel-like fibers called mucilage, which is why it has long been used for coughs, sore throats,...

Marshmallow monograph & interactions

Cranberry concentrate

Interacts with
712 drugs
150 mg per serving

Cranberry is best known for helping to prevent repeated urinary tract infections (UTIs) in some people, and the evidence here is moderate but mixed. I...

Cranberry concentrate monograph & interactions

Buchu leaf extract

Interacts with
481 drugs
300 mg per serving

Buchu is a fragrant South African shrub whose leaves are traditionally used for urinary and bladder complaints and as a diuretic. Solid human studies...

Buchu leaf extract monograph & interactions

Uva Ursi leaf extract

Interacts with
803 drugs
300 mg per serving

Uva ursi is a traditional herb used mainly for urinary tract infections, and its leaves contain a compound called arbutin that may have antimicrobial...

Uva Ursi leaf extract monograph & interactions

Pipsissewa

No known
interactions
300 mg per serving

Pipsissewa is a North American forest herb with a long history of traditional use as a diuretic and urinary remedy, but modern human research is very...

Pipsissewa monograph & interactions

Other (inactive) ingredients: Vegetarian capsule. These complete the product’s ingredient list but are not active constituents.

Interaction report

CranStat Extra by Vitanica Drug Interactions

Want to check YOUR meds against CranStat Extra?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

Go to the checker
2,197Drugs
1,383 Moderate 814 Minor

Ingredients driving the most interactions

Marshmallow 2,040
Oregon Grape 1,218

Each ingredient & the kinds of drugs it affects

For each ingredient in CranStat Extra with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Marshmallow3 drug types · 2,040 drugs

Lithium

Theoretically, due to potential diuretic effects, marshmallow might reduce excretion and increase levels of lithium.
Marshmallow is thought to have diuretic properties. To avoid lithium toxicity, the dose of lithium might need to be decreased when used with marshmallow.

Likelihood Probable Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, marshmallow flower might have antiplatelet effects.
Animal research suggests that marshmallow flower extract has antiplatelet effects. However, the root and leaf of marshmallow, not the flower, are the plant parts most commonly found in dietary supplements. Theoretically, use of marshmallow flower with anticoagulant/antiplatelet drugs can have additive effects, and might increase the risk for bleeding in some patients.

Likelihood Unlikely Evidence D
Oral Drugs

Theoretically, mucilage in marshmallow might impair absorption of oral drugs.
Marshmallow contains mucilage which can affect oral drug absorption. To avoid changes in absorption, take marshmallow 30-60 minutes after oral medications.

Likelihood Possible Evidence D

Oregon Grape9 drug types · 1,218 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, Oregon grape might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
In vitro and in vivo research suggests that berberine, a constituent of Oregon grape, can inhibit platelet aggregation.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, Oregon grape might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Clinical research suggests that berberine, a constituent of Oregon grape, can lower blood glucose levels.

Likelihood Possible Evidence A
Antihypertensive Drugs

Theoretically, Oregon grape might increase the risk of hypotension when taken with antihypertensive drugs.
Animal research suggests that berberine, a constituent of Oregon grape, can have hypotensive effects. Also, an analysis of clinical evidence suggests that taking berberine in combination with amlodipine (Norvasc) can lower systolic and diastolic blood pressure when compared with taking amlodipine alone.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, Oregon grape might increase the sedative effects of CNS depressants.
Animal research suggests that berberine, a constituent of Oregon grape, can have sedative effects.

Likelihood Possible Evidence D
Cyclosporine (Neoral, Sandimmune)

Theoretically, Oregon grape might increase the effects and adverse effects of cyclosporine.
Berberine, a constituent of Oregon grape, can reduce metabolism of cyclosporine and increase serum levels. It might inhibit cytochrome P450 3A4 (CYP3A4), which metabolizes cyclosporine.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, Oregon grape might increase serum levels of drugs metabolized by CYP2C9.
Preliminary clinical evidence suggests that berberine, a constituent of Oregon grape, can inhibit cytochrome P450 2C9 (CYP2C9).

Likelihood Possible Evidence B
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, Oregon grape might increase serum levels of drugs metabolized by CYP2D6.
In vitro research and preliminary clinical evidence suggest that berberine, a constituent of Oregon grape, can inhibit cytochrome P450 2D6 (CYP2D6).

Likelihood Possible Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, Oregon grape might increase serum levels of drugs metabolized by CYP3A4.
In vitro research and preliminary clinical evidence suggest that berberine, a constituent of Oregon grape, moderately inhibits cytochrome P450 3A4 (CYP3A4).

Likelihood Possible Evidence D
P-Glycoprotein Substrates

Theoretically, Oregon grape might increase serum levels of drugs that are P-glycoprotein (P-gp) substrates.
In vitro research suggests that Oregon grape extracts inhibit P-gp efflux.

Likelihood Possible Evidence D

Uva Ursi leaf extract6 drug types · 803 drugs

Cytochrome P450 2C19 (Cyp2C19) Substrates

Theoretically, uva ursi may decrease the metabolism of CYP2C19 substrates.
In vitro, uva ursi appears to inhibit cytochrome CYP2C19. This effect has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, uva ursi may decrease the metabolism of CYP3A4 substrates.
In vitro, uva ursi appears to inhibit CYP3A4. This effect has not been reported in humans.

Likelihood Possible Evidence D
Glucuronidated Drugs

Theoretically, uva ursi may increase levels of drugs metabolized by glucuronidation.
In vitro, uva ursi extract appears to strongly inhibit UDP-glucuronosyltransferase (UGT) 1A1 (UGT1A1). However, uva ursi extract does not appear to inhibit UGT1A1 in animal models. This effect has not been reported in humans.

Likelihood Possible Evidence D
Lithium

Theoretically, uva ursi may increase lithium levels, necessitating a decrease in dose.
Uva ursi may have diuretic properties. Diuretics may increase lithium reabsorption with sodium in the proximal tubule of the kidney. Theoretically, uva ursi might reduce excretion and increase levels of lithium.

Likelihood Probable Evidence D
Urinary Acidifying Agents

Effects of uva ursi in the urinary tract may be reduced by urinary acidifying agents.
Uva ursi seems to work best in alkaline urine. Theoretically, taking uva ursi with medications known to acidify the urine may decrease any effects of uva ursi on the urinary tract.

Likelihood Possible Evidence D
P-Glycoprotein Substrates

Theoretically, uva ursi may alter the levels of drugs transported by P-glycoprotein.
In vitro, uva ursi appears to inhibit the multi-drug transporter protein, P-glycoprotein. This effect has not been reported in humans.

Likelihood Possible Evidence D

Cranberry concentrate6 drug types · 712 drugs

Atorvastatin (Lipitor)

Theoretically, cranberry might increase levels and adverse effects of atorvastatin.
In one case report, a patient taking atorvastatin experienced upper back pain, rhabdomyolysis, and abnormal liver function after drinking cranberry juice 16 ounces daily for 2 weeks. Theoretically, this may have been caused by inhibition of cytochrome P450 3A4 (CYP3A4) enzymes by cranberry juice, as atorvastatin is a CYP3A4 substrate. Creatinine kinase and liver enzymes normalized within 2 weeks of stopping cranberry juice. Patients taking atorvastatin should avoid large quantities of cranberry juice.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, cranberry might increase the levels and adverse effects of CYP3A4 substrates.
A case of upper back pain, rhabdomyolysis, and abnormal liver function has been reported for a patient taking atorvastatin, a CYP3A4 substrate, in combination with cranberry juice 16 ounces daily for 2 weeks. Creatinine kinase and liver enzymes normalized within 2 weeks of stopping cranberry juice. Also, animal research suggests that cranberry juice, administered intraduodenally 30 minutes prior to nifedipine, a CYP3A4 substrate, inhibits nifedipine metabolism and increases the area under the concentration-time curve by 1.6-fold compared to control.

Likelihood Possible Evidence D
Nifedipine (Procardia)

Theoretically, cranberry might increase the levels and adverse effects of nifedipine.
Animal research suggests that cranberry juice, administered intraduodenally 30 minutes prior to nifedipine treatment, inhibits nifedipine metabolism and increases the area under the concentration-time curve by 1.6-fold compared to control. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, cranberry might increase the levels and adverse effects of warfarin. However, research is conflicting.
There is contradictory evidence about the effect of cranberry juice on warfarin. Case reports have linked cranberry juice consumption to increases in the international normalized ratio (INR) in patients taking warfarin, resulting in severe spontaneous bleeding and excessive postoperative bleeding. Daily consumption of cranberry sauce for one week has also been linked to an increase in INR in one case report. In a small study in healthy young males, taking a high dose of 3 grams of cranberry juice concentrate capsules, equivalent to 57 grams of fruit daily, for 2 weeks produced a 30% increase in the area under the INR-time curve after a single 25-mg dose of warfarin. However, 3 very small clinical studies in patients stabilized on warfarin reported that cranberry juice 250 mL once or twice daily for 7 days (27% cranberry juice or pure cranberry juice) or 240 mL once daily for 14 days does not significantly increase INR or affect plasma warfarin levels. The reasons for these discrepant findings are unclear. It is possible that the form and dose of cranberry may play a role, as cranberry extracts and juices contain different constituents. Additionally, an in vitro study evaluating 5 different cranberry juices found varying effects, with only a cranberry concentrate, and not diluted cranberry juices, inhibiting CYP2C9. However, this concentrate did not inhibit CYP2C9 activity in humans.

Likelihood Possible Evidence B
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, cranberry might increase the levels and adverse effects of CYP2C9 substrates. However, research is conflicting.
There is contradictory evidence about the effect of cranberry on CYP2C9 enzymes. In vitro evidence suggests that flavonoids in cranberry inhibit CYP2C9 enzymes. However, clinical research shows that cranberry juice does not significantly affect the levels, metabolism, or elimination of the CYP2C9 substrates flurbiprofen or diclofenac. Also, in patients stabilized on warfarin, drinking cranberry juice 250 mL daily for 7 days does not significantly increase the anticoagulant activity of warfarin, a CYP2C9 substrate. Additional pharmacokinetic research shows that cranberry juice does not increase peak plasma concentrations or area under the concentration-time curve of warfarin.

Likelihood Unlikely Evidence B
Diclofenac (Voltaren, Others)

Theoretically, cranberry might modestly increase the levels and adverse effects of diclofenac.
In vitro evidence suggests that cranberry juice inhibits diclofenac metabolism by human liver microsomes. However, drinking cranberry juice does not seem to affect diclofenac metabolism in humans.

Likelihood Unlikely Evidence B

Buchu leaf extract3 drug types · 481 drugs

Anticoagulant/Antiplatelet Drugs

Buchu may have antiplatelet effects. Theoretically, buchu may enhance the effects of anticoagulant or antiplatelet drugs and increase the risk of bleeding in some patients. Some anticoagulant or antiplatelet drugs include aspirin, clopidogrel (Plavix), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, ticlopidine (Ticlid), warfarin (Coumadin), and others.

Likelihood Possible Evidence D
Hepatotoxic Drugs

Buchu contains pulegone, a known hepatotoxin. There is some concern that buchu may adversely affect the liver, especially when the leaf is used in large doses or the oil is ingested. Theoretically, concomitant use with hepatotoxic drugs might increase the risk of liver damage. Some of these drugs include acarbose (Precose, Prandase), amiodarone (Cordarone), atorvastatin (Lipitor), azathioprine (Imuran), carbamazepine (Tegretol), cerivastatin (Baycol), diclofenac (Voltaren), felbamate (Felbatol), fenofibrate (Tricor), fluvastatin (Lescol), gemfibrozil (Lopid), isoniazid, itraconazole, (Sporanox), ketoconazole (Nizoral), leflunomide (Arava), lovastatin (Mevacor), methotrexate (Rheumatrex), nevirapine (Viramune), niacin, nitrofurantoin (Macrodantin), pioglitazone (Actos), pravastatin (Pravachol), pyrazinamide, rifampin (Rifadin), ritonavir (Norvir), rosiglitazone (Avandia), simvastatin (Zocor), tacrine (Cognex), tamoxifen, terbinafine (Lamisil), valproic acid, and zileuton (Zyflo)

Likelihood Possible Evidence D
Lithium

Buchu is thought to have diuretic properties. Theoretically, buchu might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.

Likelihood Probable Evidence D
The maker

Brand information

Manufacturer and brand details for CranStat Extra, from the product label.

Vitanica

See all Vitanica products
Name
VITANICA(R)
Street Address
10347 SW Spokane Ct.
City
Tualatin
State
OR
ZipCode
97062
Web Address
www.vitanica.com
Pharmacist Counseling Corner

CranStat Extra by Vitanica: Common Questions

Does CranStat Extra by Vitanica interact with any medications?
Yes. Based on its ingredients, CranStat Extra has a known interaction with 2,197 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
CranStat Extra contains 6 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take CranStat Extra if I'm pregnant or breastfeeding?
Oregon grape in this product is rated likely unsafe during pregnancy and breastfeeding, and the other herbal ingredients also lack safe-use data for these times. Don't use CranStat Extra if you're pregnant or nursing — talk with your OB or midwife about other options.
Does cranberry in this product really help with UTIs?
Cranberry concentrate is rated possibly effective for urinary tract infections, but uva ursi in the same formula is rated possibly ineffective for UTIs, so the two ingredients work against each other. The overall benefit is uncertain.
What side effects might I notice?
Cranberry can cause diarrhea and stomach discomfort in some people. Uva ursi may cause diarrhea, nausea, stomach upset, and vomiting. With chronic or very high doses of uva ursi, serious effects like ringing in the ears, convulsions, and delirium are rare but possible.
I take lithium for bipolar disorder — is this product safe?
No — marshmallow, buchu, and uva ursi all have interactions with lithium and could raise its levels in your blood to unsafe ranges. Do not take CranStat Extra without talking to your prescriber first.
Can I take this at the same time as my other medications?
Marshmallow may slow how your body absorbs other oral drugs. To be safe, take CranStat Extra 30–60 minutes after your other medications. For all other ingredients, use the medication checker on this page to see if your specific drugs interact.

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

Not sure if CranStat Extra is safe with your meds?

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Ask a pharmacist

Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

CranStat Extra label
Go deeper

The Full Monographs Behind CranStat Extra’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Oregon Grape

Interacts with 1,218 drugs

Oregon grape is a shrub whose root contains berberine and related compounds. The strongest (though still modest) evidence is for topical creams that may slightly ease psoriasis; evidence for...

Read the full Oregon Grape monograph →
Herb & supplement monograph

Marshmallow

Interacts with 2,040 drugs

Marshmallow root is a traditional herb rich in soothing, gel-like fibers called mucilage, which is why it has long been used for coughs, sore throats, and stomach irritation. Evidence for th...

Read the full Marshmallow monograph →
Herb & supplement monograph

Cranberry

Interacts with 712 drugs

Cranberry is best known for helping to prevent repeated urinary tract infections (UTIs) in some people, and the evidence here is moderate but mixed. It is not a reliable treatment for an act...

Read the full Cranberry monograph →
Herb & supplement monograph

Buchu

Interacts with 481 drugs

Buchu is a fragrant South African shrub whose leaves are traditionally used for urinary and bladder complaints and as a diuretic. Solid human studies are lacking, so its benefits are largely...

Read the full Buchu monograph →
Herb & supplement monograph

Uva Ursi

Interacts with 803 drugs

Uva ursi is a traditional herb used mainly for urinary tract infections, and its leaves contain a compound called arbutin that may have antimicrobial effects in the urine. Evidence in people...

Read the full Uva Ursi monograph →
Herb & supplement monograph

Pipsissewa

Pipsissewa is a North American forest herb with a long history of traditional use as a diuretic and urinary remedy, but modern human research is very limited. There is not enough good eviden...

Read the full Pipsissewa monograph →
Sources

Sources & How We Checked

CranStat Extra's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

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

The 71 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Oregon Grape 21 references
  1. Wiesenauer M, Lydtke R. Mahonia aquifolium in patients with Psoriasis vulgaris; an intraindividual study. Phytomedicine 1996;3:231-5.
  2. Chan E. Displacement of bilirubin from albumin by berberine. Biol Neonate 1993;63:201-8. PubMed
  3. Janbaz KH, Gilani AH. Studies on preventive and curative effects of berberine on chemical-induced hepatotoxicity in rodents. Fitoterapia 2000;71:25-33.. PubMed
  4. Wu X, Li Q, Xin H, Yu A, Zhong M. Effects of berberine on the blood concentration of cyclosporin A in renal transplanted recipients: clinical and pharmacokinetic study. Eur J Clin Pharmacol 2005;61:567-72. PubMed
  5. Gulliver WP, Donsky HJ. A report on three recent clinical trials using Mahonia aquifolium 10% topical cream and a review of the worldwide clinical experience with Mahonia aquifolium for the treatment of plaque psoriasis. Am J Ther 2005;12:398-406. PubMed
  6. Zhang Y, Li X, Zou D, et al. Treatment of type 2 diabetes and dyslipidemia with the natural plant alkaloid berberine. J Clin Endocrinol Metab 2008;93:2559-65. PubMed
  7. Budzinski JW, Foster BC, Vandenhoek S, Arnason JT. An in vitro evaluation of human cytochrome P450 3A4 inhibition by selected commercial herbal extracts and tinctures. Phytomedicine 2000;7:273-82. PubMed
  8. Chatterjee P, Franklin MR. Human cytochrome p450 inhibition and metabolic-intermediate complex formation by goldenseal extract and its methylenedioxyphenyl components. Drug Metab Dispos 2003;31:1391-7. PubMed
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Buchu 3 references
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Uva Ursi 8 references
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Pipsissewa 1 reference
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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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