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Dietary supplement

Periwinkle Ingredients & Drug Interactions

by Hawaii Pharm

Periwinkle label
See full label image
Liquid Category: Botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 30, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Periwinkle against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

Periwinkle is a dietary supplement by Hawaii Pharm with 1 active ingredient. Its ingredients are commonly taken for memory and cognitive support, circulation problems, dizziness and ringing in the ears.Based on those ingredients, 172 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are certified organic Periwinkle extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Periwinkle by Hawaii Pharm

Ask about any prescription or over-the-counter medication and we check it for interactions with Periwinkle by Hawaii Pharm — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Periwinkle by Hawaii Pharm

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

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 2026

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 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: certified organic periwinkle extract. Periwinkle is a plant whose leaves contain powerful compounds called vinca alkaloids, which have been studied for their effects on blood pressure and circulation.

The liquid also includes vegetable palm glycerin and pharmaceutical-grade alcohol as inactive ingredients to preserve and deliver the extract.

Does it work?

Couldn't assess
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
Not assessable

This is a single-ingredient Periwinkle product and its label doesn't state a use — see Periwinkle's own graded uses on its monograph.

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.

The product facts we have don't include effectiveness ratings for periwinkle extract, so the evidence isn't established in the data we hold.

The evidence, ingredient by ingredient Periwinkle

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 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Here's what you need to know: periwinkle contains strong alkaloids that can be toxic at higher doses, and the product should only be used with professional guidance. The safety data advises against use during pregnancy and while breastfeeding because of its potent alkaloids and lack of safety information.

Orally, periwinkle can cause serious side effects including damage to the liver, kidneys, and nervous system due to its vinca alkaloid content. It's also been reported to cause stomach upset, skin flushing, and low blood pressure.

Side effects, ingredient by ingredient Periwinkle

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?
  • 1 of the 1 matched ingredient can interact with medications — Periwinkle.
  • The most serious interaction on file is rated Moderate.
  • For scale: 172 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.

If you take blood pressure–lowering drugs (antihypertensives), check with your pharmacist before adding periwinkle. The extract may increase how much those medications lower your pressure.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no assessable stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Periwinkle is not a typical over-the-counter supplement — it's a potent plant extract with real risks. If you're considering it, talk to your pharmacist or doctor first, especially if you take blood pressure medication.

Do not use it if you're pregnant or breastfeeding.

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

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Nov 21, 2020.

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 Periwinkle, straight from the product label.

Brand Hawaii Pharm
Barcode (UPC) 650905465321
Net contents 4 Fluid Ounce(s); 120 mL
Market status On market
Date entered into DSLD Nov 21, 2020
DSLD ID 237585
Product type Botanical
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Organic, Gluten 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 Periwinkle by Hawaii Pharm, 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:
0.7 mL
Maximum serving Sizes:
1 mL
Servings per container
120
UPC/BARCODE
650905465321
IngredientAmount% DV
certified organic Periwinkle extract970 mg--

Other ingredients: Vegetable Palm Glycerin, pharmaceutical grade Alcohol

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

Hawaii Pharm Herbal Extract Highest quality since 2008

Made with Aloha!

Formulation

Contains no GMO, gluten, artificial colors, heavy metals, preservatives, pesticides, fertilizers.

Super concentrated liquid herbal extract. Dry herb/menstruum ratio: 1:3.

Manufactured in an FDA registered facility.

Non GMO Gluten free

Made in USA, Hawaii

Suggested/Recommended/Usage/Directions

Directions for use: Shake well before using. Take about 20-30 drops (0.7-1 ml, one full squeeze of the dropper bulb) to 2-4 oz of juice or water up to 4 times per day.

Precautions

Warning: Keep out of the reach of children.

May have contraindications. We recommend to seek expert medical advice before taking.

Do not use if you are allergic to any ingredients.

Consult a physician before using during pregnancy, if nursing or taking any medications.

Do not use if seal is broken or missing.

Storage

Store in a cool dry place.

Formula

(Vinca minor)

FDA Statement of Identity

Herbal Dietary Supplement

FDA Disclaimer Statement

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

Seals/Symbols

FDA Registered Facility Made in United States of America USA

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Periwinkle by Hawaii Pharm label

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

Periwinkle label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Periwinkle by Hawaii Pharm

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size0.7 mL Dosage formLiquid Servings per container120 Amounts shown are per serving.

Certified organic Periwinkle extract

Interacts with
172 drugs
970 mg per serving

Periwinkle (Vinca minor) is a flowering plant whose alkaloids are the source of vinpocetine, a compound marketed for memory and brain circulation. Evi...

Certified organic Periwinkle extract monograph & interactions

Other (inactive) ingredients: Vegetable Palm Glycerin, Pharmaceutical grade Alcohol. These complete the product’s ingredient list but are not active constituents.

Interaction report

Periwinkle by Hawaii Pharm Drug Interactions

Want to check YOUR meds against Periwinkle?

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
172Drugs
172 Moderate

Ingredients driving the most interactions

certified organic Periwinkle extract 172

Individual Drug Interactions

The ingredients in Periwinkle interact with 172 drugs. Click any drug to see the details.

1 of the 1 ingredient in Periwinkle interact with drugs. Each result below shows which ingredient is responsible. certified organic Periwinkle extract

Each ingredient & the kinds of drugs it affects

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

certified organic Periwinkle extract1 drug type · 172 drugs

Antihypertensive Drugs

Theoretically, taking periwinkle may increase the effects of antihypertensive drugs due to the hypotensive activity of vincamine, a constituent of periwinkle.

Likelihood Probable Evidence D
certified organic Periwinkle extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Periwinkle, from the product label.

Hawaii Pharm

See all Hawaii Pharm products
Name
Hawaii Pharm LLC
City
Honolulu
State
HI
ZipCode
96815
Web Address
www.hawaiipharm.com
Pharmacist Counseling Corner

Periwinkle by Hawaii Pharm: Common Questions

Does Periwinkle by Hawaii Pharm interact with any medications?
Yes. Based on its ingredients, Periwinkle has a known interaction with 172 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Periwinkle contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism 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 this while pregnant or breastfeeding?
No. The safety data advises against periwinkle during pregnancy and breastfeeding because of its potent alkaloids and lack of safety information. Talk to your doctor if you're considering it in either situation.
What are the main side effects?
Periwinkle can cause serious effects including liver and kidney damage, nerve damage, stomach upset, skin flushing, and low blood pressure. It's considered unsafe for oral use because of its vinca alkaloid content.
Why does the label say it should only be used with professional advice?
Because periwinkle contains strong alkaloids that can be toxic at higher doses. You need guidance from a healthcare provider to use it safely, if at all.
What is vincamine and why does it matter for my blood pressure meds?
Vincamine is one of the active alkaloids in periwinkle. It can lower blood pressure on its own, so if you're already on blood pressure medication, periwinkle may make that medication work too well and drop your pressure dangerously low.

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

Not sure if Periwinkle is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

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.

Periwinkle label
Go deeper

The Full Monographs Behind Periwinkle’s Ingredients

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

Herb & supplement monograph

Periwinkle

Interacts with 172 drugs

Periwinkle (Vinca minor) is a flowering plant whose alkaloids are the source of vinpocetine, a compound marketed for memory and brain circulation. Evidence in humans is limited and mixed, an...

Read the full Periwinkle monograph →
Sources

Sources & How We Checked

Periwinkle'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 5 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.

Periwinkle 5 references
  1. Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
  2. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  3. Ellenhorn MJ, et al. Ellenhorn's Medical Toxicology: Diagnoses and Treatment of Human Poisoning. 2nd ed. Baltimore, MD: Williams & Wilkins, 1997.
  4. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  5. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.

See these in context on the Periwinkle monograph →

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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