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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 16, 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 Periwinkle Leaf Extract, Dry. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

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.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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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: Periwinkle Leaf Extract, Dry. The extract includes alkaloid compounds, chiefly vincamine, which affect blood pressure and have other systemic effects.

The liquid also contains alcohol, water, and glycerin as inactive ingredients.

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.

We hold no effectiveness ratings for periwinkle in our data, so the evidence for what it may accomplish isn't established here.

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.

Periwinkle is generally regarded as unsafe for oral use. The alkaloids it contains—particularly the vinca alkaloids—can cause serious damage to your liver, kidneys, and nervous system, along with gastrointestinal upset, skin flushing, and dangerously low blood pressure.

Because of these potent alkaloids and limited safety data, periwinkle should be avoided during pregnancy and while breastfeeding. The product carries a caution that it should only be used under professional guidance and at careful doses.

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 any blood pressure medication (antihypertensive), check it against the search tool below before using this product. Periwinkle may increase its effect and lower your blood pressure too much.

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 a high-risk herbal extract with documented toxicity and serious drug interactions. It's not a first-choice supplement for most people.

If you're considering it, you need your pharmacist or doctor's direct supervision beforehand—do not self-dose. Pregnant or breastfeeding?

Skip it entirely.

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 Oct 24, 2023.

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) 840253640932
Net contents 4 Fluid Ounce(s); 120 mL
Market status On market
Date entered into DSLD Oct 24, 2023
DSLD ID 301707
Product type Botanical
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), 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
840253640932
IngredientAmount% DV
Periwinkle Leaf Extract, Dry983 mg--

Other ingredients: Alcohol, Water, Glycerin

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.
Brand IP Statement(s)

Hawaii Pharm Herbal Extract Highest quality since 2008

Suggested/Recommended/Usage/Directions

Suggested use: Shake well before using. For adults add about 20-30 drops (0.7-1 mL, one full squeeze of the dropper bulb) to some juice or water, up to 4 times a day.

Precautions

Warning: We recommend to seek expert medical advice before taking.

Do not use if you are allergic to any ingredients.

Consult your physician before giving to children under 18, during pregnancy, if nursing or taking medications.

Consult your physician before giving to children under 18, during pregnancy, if nursing or taking medications.

May affect the ability to drive and operate machinery. May have contraindications, can cause side effects and adverse reactions. Do not use if seal is broken or missing.

Keep out of the reach of children!

Storage

Store in a cool dry place.

Seals/Symbols

cGMP Made in compliance with cGMP 21 CFR 111 in an FDA registered and inspected facility.

Organic Alcohol Based USA Made in United States of America

FDA Disclaimer Statement

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

General Statements

Scan this QR-code to get 15% discount on your next purchase. Limited time deal.

Formula

Vinca minor

Organic Alcohol Based

Formulation

Only natural ingredients Purity is laboratory tested and verified

All the raw materials are gluten-free by their nature No artificial colors, flavors, or preservatives

Not tested on animals

Organic Alcohol Based

Made in USA, Hawaii

FDA Statement of Identity

Herbal Supplement

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.

Periwinkle Leaf Extract, Dry

Interacts with
172 drugs
983 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...

Periwinkle Leaf Extract, Dry monograph & interactions

Other (inactive) ingredients: Alcohol, Water, Glycerin. 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

Periwinkle Leaf Extract, Dry 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. Periwinkle Leaf Extract, Dry

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.

Periwinkle Leaf Extract, Dry1 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
Periwinkle Leaf Extract, Dry 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
Street Address
510 Sumner St. Ste. 613
City
Honolulu
State
HI
ZipCode
96817
Phone Number
888-854-2924
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.
What's actually in this product?
One active ingredient: periwinkle leaf extract, which contains strong alkaloids (chemical compounds). The rest is alcohol, water, and glycerin.
Can I take this while pregnant or breastfeeding?
No. The safety data advises against it during both pregnancy and breastfeeding because of the potent alkaloids and lack of safety information.
What are the side effects I should watch for?
Gastrointestinal complaints, skin flushing, and low blood pressure are the most common. More serious—liver, kidney, and nerve damage—can happen because of the vinca alkaloids, especially at higher doses.
Is this safe to use long-term?
Periwinkle is regarded as unsafe for oral use and should only be taken under professional guidance. Long-term safety data is not available, and the risk of organ damage from its alkaloids is real.

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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