Periwinkle

What Is Periwinkle?

Greater periwinkle is a trailing evergreen ground cover in the dogbane family, grown worldwide for its blue-violet flowers and glossy leaves. In older European herbal medicine it was an astringent, used for heavy menstrual bleeding and other bleeding ^{14Reference 14Grieve · 1931Periwinkles — Greater periwinkle (Vinca major): uses as an astringent and tonic — herbal referenceView study →}.

Vinca major comes from the Mediterranean region and is planted in gardens across the temperate world, where it often escapes and spreads ^{16,20Reference 16Fishbein et al.E., & Krings, AView study →Reference 20Weeds Australia (n.d.)Blue periwinkle (Vinca major) — weed profile: origin, impacts and toxicity to livestockView study →}.

Its chemistry is a family of monoterpene indole alkaloids ^{1,2Reference 1Janot et al. · 1954Vinca major L. alkaloids: presence of reserpinine — phytochemical studyView study →Reference 2Farnsworth et al. · 1962Studies on Vinca major (Apocynaceae)View study →}. The cognitive research on “periwinkle” concerns vincamine, an alkaloid obtained mainly from lesser periwinkle, and vinpocetine, a synthetic compound made from it ^{3Reference 3Szatmári et al. · 2003Meta-analysisVinpocetine for cognitive impairment and dementia — Cochrane systematic review and meta-analysisView study →}. Greater periwinkle itself has only laboratory studies.

Two other plants share the name. Lesser periwinkle (Vinca minor) is a smaller relative. Madagascar periwinkle (Catharanthus roseus) belongs to a different genus and is the source of the cancer drugs vinblastine and vincristine, which do not occur in greater periwinkle ^{2,15Reference 2Farnsworth et al. · 1962Studies on Vinca major (Apocynaceae)View study →Reference 15Kumar et al. · 2022ReviewCatharanthus roseus (L.) GView study →}.

How Is Periwinkle Used?

• Dried aerial parts — the traditional astringent, taken in small amounts or used as a gargle ^{14Reference 14Grieve · 1931Periwinkles — Greater periwinkle (Vinca major): uses as an astringent and tonic — herbal referenceView study →}.
• Ointment — applied to piles and inflamed skin ^{14Reference 14Grieve · 1931Periwinkles — Greater periwinkle (Vinca major): uses as an astringent and tonic — herbal referenceView study →}.
• Isolated alkaloids — vincamine and vinpocetine are sold for memory and circulation, but are made from lesser periwinkle, not this plant ^{3Reference 3Szatmári et al. · 2003Meta-analysisVinpocetine for cognitive impairment and dementia — Cochrane systematic review and meta-analysisView study →}.

Traditional Uses

European Herbal Medicine

Greater periwinkle was the periwinkle more generally used in European herbal medicine. It was taken as an astringent and tonic for menorrhagia and other bleeding, and also as a laxative ^{14Reference 14Grieve · 1931Periwinkles — Greater periwinkle (Vinca major): uses as an astringent and tonic — herbal referenceView study →}.

It was used as a gargle for mouth and throat complaints, and made into an ointment for piles and inflammatory skin conditions ^{14Reference 14Grieve · 1931Periwinkles — Greater periwinkle (Vinca major): uses as an astringent and tonic — herbal referenceView study →}. The astringency has been attributed to its tannins.

Indications

• Heavy menstrual bleeding [aerial parts; European herbal medicine]
• Bleeding [aerial parts; European herbal medicine]
• Diarrhoea [aerial parts; European herbal medicine]
• Mouth ulcers and sore throat, as a gargle [aerial parts; European herbal medicine]
• Piles and inflamed skin, as an ointment [aerial parts; European herbal medicine]
• Cognitive decline and dementia [isolated vincamine; vinpocetine] ⚠Caution: The trials used purified vincamine and vinpocetine, which come from lesser periwinkle. No study has tested greater periwinkle itself ^3,5.

Botany

Greater periwinkle is a trailing, evergreen perennial in the dogbane family, Apocynaceae. Its main stems lie along the ground and root at the nodes, while the flowering stems stand upright ^{18,19Reference 18Nazimuddin et al.Nazimuddin, S., & Qaiser, M. (n.d.). Vinca major — species description and distribution. In Flora of Pakistan (Apocynaceae). eFloras. http://www.efloras.org/florataxon.aspx?flora_id=5&taxon_id=200018490View study →Reference 19NC State Extension (n.d.)Vinca major — description, native range, invasive status and identification — species databaseView study →}.

The leaves grow in opposite pairs. They are ovate, 2.5–9 cm long, with heart-shaped to squared-off bases and margins fringed with fine hairs ^{16,17Reference 16Fishbein et al.E., & Krings, AView study →Reference 17Li et al.Li, B., Leeuwenberg, A. J. M., & Middleton, D. J. (n.d.). Vinca major — species description. In Flora of China, Vol. 16 (Apocynaceae). eFloras. http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=200018490View study →}.

The flowers grow singly from the leaf axils. They are blue-purple, rarely violet or white, 3–5 cm across, with five lopsided, spreading lobes ^{16,17Reference 16Fishbein et al.E., & Krings, AView study →Reference 17Li et al.Li, B., Leeuwenberg, A. J. M., & Middleton, D. J. (n.d.). Vinca major — species description. In Flora of China, Vol. 16 (Apocynaceae). eFloras. http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=200018490View study →}. They open in spring and, in warm climates, through much of the year ^{16Reference 16Fishbein et al.E., & Krings, AView study →}.

The fruit is a pair of slender pods, 2.5–5 cm long ^{16Reference 16Fishbein et al.E., & Krings, AView study →}. In cultivation it rarely sets fruit ^{19Reference 19NC State Extension (n.d.)Vinca major — description, native range, invasive status and identification — species databaseView study →}.

It can be told from lesser periwinkle by its leaves. Those of greater periwinkle are broadest below the middle, thin, with heart-shaped to rounded bases and hair-fringed margins; those of lesser periwinkle are broadest near the middle, thicker, and not fringed ^{19Reference 19NC State Extension (n.d.)Vinca major — description, native range, invasive status and identification — species databaseView study →}. Greater periwinkle also has the larger flowers ^{19Reference 19NC State Extension (n.d.)Vinca major — description, native range, invasive status and identification — species databaseView study →}.

Distribution

Greater periwinkle is native to southern Europe and the Mediterranean, including northern Africa and Asia Minor ^{16,18,20Reference 16Fishbein et al.E., & Krings, AView study →Reference 18Nazimuddin et al.Nazimuddin, S., & Qaiser, M. (n.d.). Vinca major — species description and distribution. In Flora of Pakistan (Apocynaceae). eFloras. http://www.efloras.org/florataxon.aspx?flora_id=5&taxon_id=200018490View study →Reference 20Weeds Australia (n.d.)Blue periwinkle (Vinca major) — weed profile: origin, impacts and toxicity to livestockView study →}.

It has been planted as an ornamental across the temperate world and commonly spreads from cultivation. It is naturalised across much of the United States and in British Columbia, where it grows in open woodland, along streams and on old home sites ^{16Reference 16Fishbein et al.E., & Krings, AView study →}.

It is listed as invasive in several US states ^{19Reference 19NC State Extension (n.d.)Vinca major — description, native range, invasive status and identification — species databaseView study →}, and as a serious environmental weed in the temperate regions of southern Australia ^{20Reference 20Weeds Australia (n.d.)Blue periwinkle (Vinca major) — weed profile: origin, impacts and toxicity to livestockView study →} and in New Zealand ^{21Reference 21New Zealand Plant Conservation Network (Vinca major — naturalisation and environmental weed statusView study →}. Its rooting stems form dense mats that crowd out native ground flora, and broken pieces carried by water start new colonies ^{19,20Reference 19NC State Extension (n.d.)Vinca major — description, native range, invasive status and identification — species databaseView study →Reference 20Weeds Australia (n.d.)Blue periwinkle (Vinca major) — weed profile: origin, impacts and toxicity to livestockView study →}.

Where it has escaped, pulling it up for use removes an invasive plant rather than depleting a wild one.

Growing Conditions

Cultivation snapshot for Periwinkle

SunFull sun to part shadeWaterDry to mediumSoilAverage, dry to medium, well-drainedLifeperennialZoneUSDA 7-9

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Phytochemistry

Greater periwinkle contains monoterpene indole alkaloids ^{1,2Reference 1Janot et al. · 1954Vinca major L. alkaloids: presence of reserpinine — phytochemical studyView study →Reference 2Farnsworth et al. · 1962Studies on Vinca major (Apocynaceae)View study →}. Those reported include vincamajine, reserpinine, majdine, eburnamenine and 11-hydroxypolyneuridine, a new alkaloid isolated from plants growing in Turkey ^{1,2,4Reference 1Janot et al. · 1954Vinca major L. alkaloids: presence of reserpinine — phytochemical studyView study →Reference 2Farnsworth et al. · 1962Studies on Vinca major (Apocynaceae)View study →Reference 4Bahadori et al. · 2012Indole alkaloids from Vinca major and V. minor growing in Turkey — antioxidant and anticholinesterase activityView study →}.

Vincamine is a minor component. It is obtained commercially from lesser periwinkle, and vinpocetine is a synthetic ethyl ester of apovincamine, a compound derived from it ^{3Reference 3Szatmári et al. · 2003Meta-analysisVinpocetine for cognitive impairment and dementia — Cochrane systematic review and meta-analysisView study →}.

Later studies isolated further alkaloid groups: three monoterpenoid indole alkaloids from the whole plant ^{10Reference 10Zhang et al. · 2016Three new monoterpenoid indole alkaloids from Vinca major — cytotoxicity screenView study →}, and three pyridine alkaloids from plants grown in Pakistan ^{11Reference 11Wei et al. · 2017Three new pyridine alkaloids from Vinca major cultivated in Pakistan — cytotoxicity screen (inactive)View study →}.

The leaves and stems also contain non-alkaloid compounds, including a new iridoid glycoside ^{6Reference 6Cheng et al. · 2016Non-alkaloid constituents of Vinca major — a new iridoid glycoside with DPPH antioxidant activityView study →}, and the plant contains astringent tannins.

Alkaloid levels vary with growing conditions, and no standard assay for the whole herb exists ^{2Reference 2Farnsworth et al. · 1962Studies on Vinca major (Apocynaceae)View study →}.

Constituent Summary

Published alkaloid amounts for the whole herb are sparse.

Pharmacology & Research

Fewer than three dozen indexed papers name Vinca major, and most describe the isolation of its alkaloids rather than tests of their effects ^{1,2Reference 1Janot et al. · 1954Vinca major L. alkaloids: presence of reserpinine — phytochemical studyView study →Reference 2Farnsworth et al. · 1962Studies on Vinca major (Apocynaceae)View study →}.

The human trials in this area are of two purified compounds: vincamine, obtained mainly from lesser periwinkle, and vinpocetine, a synthetic compound made from it ^{3,5Reference 3Szatmári et al. · 2003Meta-analysisVinpocetine for cognitive impairment and dementia — Cochrane systematic review and meta-analysisView study →Reference 5Fischhof et al. · 1996RCTTherapeutic efficacy of vincamine in dementia — randomised placebo-controlled trialView study →}. The whole herb has antioxidant, cholinesterase and tyrosinase results from test-tube studies only ^{4,6,7Reference 4Bahadori et al. · 2012Indole alkaloids from Vinca major and V. minor growing in Turkey — antioxidant and anticholinesterase activityView study →Reference 6Cheng et al. · 2016Non-alkaloid constituents of Vinca major — a new iridoid glycoside with DPPH antioxidant activityView study →Reference 7Sari et al. · 2019Tyrosinase inhibitory effects of Vinca major and its secondary metabolites — enzyme kinetics and in-silico modelView study →}.

1. Cognitive Decline & Dementia

The human evidence here is entirely for purified alkaloids, not Vinca major leaf.

In a 12-week double-blind trial, vincamine at 30 mg twice daily was superior to placebo on all four main outcomes in patients with mild to moderate Alzheimer-type or vascular dementia; 152 patients entered and 142 completed ^{5Reference 5Fischhof et al. · 1996RCTTherapeutic efficacy of vincamine in dementia — randomised placebo-controlled trialView study →}.

A Cochrane review of vinpocetine included three randomised trials with 583 patients, all run before the 1990s. The trials showed benefit at 30 and 60 mg/day, but few patients were treated for six months or more, and the review concluded that the evidence was inconclusive and did not support clinical use. Vinpocetine had few adverse effects at those doses ^{3Reference 3Szatmári et al. · 2003Meta-analysisVinpocetine for cognitive impairment and dementia — Cochrane systematic review and meta-analysisView study →}.

A 2023 umbrella review rated the vinpocetine evidence on cognitive function as suggestive, one of three herbal medicines to reach that grade, while noting the small size and poor quality of the underlying trials ^{12Reference 12Sawangjit et al. · 2023Meta-analysisEfficacy and safety of herbal medicine on dementia and cognitive function — umbrella review of systematic reviews and meta-analysesView study →}. Vinpocetine is used for stroke and dementia in many countries ^{13Reference 13Zhang et al. · 2018ReviewAn update on vinpocetine: new discoveries and clinical implications — reviewView study →}.

Gap: no trial has tested Vinca major itself. The trial data are for single compounds obtained from a different species.

2. Antioxidant

Alkaloid extracts of V. major and V. minor collected in Turkey showed high DPPH radical-scavenging and lipid-peroxidation-inhibiting activity in vitro ^{4Reference 4Bahadori et al. · 2012Indole alkaloids from Vinca major and V. minor growing in Turkey — antioxidant and anticholinesterase activityView study →}.

Separately, a new iridoid glycoside from the leaves and stems of plants cultivated in Yunnan, China, together with two other non-alkaloid constituents, showed moderate DPPH scavenging (IC50 about 33–71 µmol/L) ^{6Reference 6Cheng et al. · 2016Non-alkaloid constituents of Vinca major — a new iridoid glycoside with DPPH antioxidant activityView study →}.

These are test-tube assays on solvent extracts and purified compounds. There is no cellular, animal or human antioxidant data.

3. Cholinesterase Inhibition

The same Turkish study reported very strong anticholinesterase activity for the alkaloid extracts of both Vinca species ^{4Reference 4Bahadori et al. · 2012Indole alkaloids from Vinca major and V. minor growing in Turkey — antioxidant and anticholinesterase activityView study →}.

Cholinesterase inhibition is the mechanism of several approved dementia drugs. This remains a single in-vitro result on a crude alkaloid fraction, with no identified active compound and no cellular or animal follow-up.

4. Tyrosinase Inhibition

A V. major extract inhibited tyrosinase, the enzyme that makes skin pigment, with an IC50 of about 20 µg/mL, against 8.6 µg/mL for the reference inhibitor kojic acid ^{7Reference 7Sari et al. · 2019Tyrosinase inhibitory effects of Vinca major and its secondary metabolites — enzyme kinetics and in-silico modelView study →}.

Two isolated compounds were more potent than kojic acid on a molar basis, and enzyme kinetics and molecular docking modelled their binding near the enzyme’s copper ions ^{7Reference 7Sari et al. · 2019Tyrosinase inhibitory effects of Vinca major and its secondary metabolites — enzyme kinetics and in-silico modelView study →}.

This points to a possible use against skin pigmentation. It is an isolated-enzyme and computer-modelling study only, with no cell, skin-model or clinical testing.

5. Antidiabetic

A crude methanolic extract of V. major inhibited α-glucosidase in vitro, but at high concentrations (IC50 values of about 430–700 µg/mL across the plants tested), and showed no urease inhibition at all ^{8Reference 8Rauf et al. · 2021In-vitro α-glycosidase and urease enzyme inhibition profile of some selected medicinal plants of PakistanView study →}.

In a South African cell-line screen of plants used for diabetes, V. major was one of the extracts whose in-vitro toxicity “raises concern for chronic use” ^{9Reference 9van de Venter et al. · 2008Antidiabetic screening and scoring of 11 plants traditionally used in South Africa — in-vitro cell-line studyView study →}.

There is no animal or human antidiabetic data.

Gap: only weak in-vitro enzyme inhibition, no in-vivo efficacy, and a cell-line toxicity flag that argues against chronic use.

6. Anticancer / Cytotoxic

Three new monoterpenoid indole alkaloids isolated from the whole plant were screened against five human cancer cell lines ^{10Reference 10Zhang et al. · 2016Three new monoterpenoid indole alkaloids from Vinca major — cytotoxicity screenView study →}.

Three new pyridine alkaloids were tested against glioma, glioblastoma and lung cancer cell lines, and none was active at 20 µg/mL ^{11Reference 11Wei et al. · 2017Three new pyridine alkaloids from Vinca major cultivated in Pakistan — cytotoxicity screen (inactive)View study →}.

The clinically used anticancer vinca alkaloids, vinblastine and vincristine, come from Catharanthus roseus, a different genus, and do not occur in V. major ^{2,15Reference 2Farnsworth et al. · 1962Studies on Vinca major (Apocynaceae)View study →Reference 15Kumar et al. · 2022ReviewCatharanthus roseus (L.) GView study →}.

Gap: constituent-level cell-line screens only, one set of them inactive.

Mechanisms

Vincamine has been studied for its effects on cerebral blood flow, and vinpocetine for phosphodiesterase-1 inhibition, which raises cAMP and cGMP. Both are purified compounds.

The whole-herb results — acetylcholinesterase, antioxidant and tyrosinase inhibition — come from test-tube studies of crude fractions and isolated compounds.

Clinical Trials

No registered trials of whole Vinca major exist. The human evidence is for isolated vincamine (one positive 12-week trial) and vinpocetine, whose dementia trials all predate the 1990s, with a small number of newer vinpocetine trials registered on ClinicalTrials.gov ^{3,5Reference 3Szatmári et al. · 2003Meta-analysisVinpocetine for cognitive impairment and dementia — Cochrane systematic review and meta-analysisView study →Reference 5Fischhof et al. · 1996RCTTherapeutic efficacy of vincamine in dementia — randomised placebo-controlled trialView study →}.

Last checked: July 2026.

Dosage

There is no established whole-herb dose. The crude plant is regarded as toxic and is not used as a self-administered simple.

The only quantified doses are for the isolated compounds. They are shown for reference and are not whole-herb doses.

Traditional Dosage

Safety & Pregnancy

Greater periwinkle contains toxic indole alkaloids in variable amounts and is not used as a self-administered simple.

Full Safety Detail

Toxicity. Greater periwinkle contains monoterpene indole alkaloids in unstandardised amounts ^{2Reference 2Farnsworth et al. · 1962Studies on Vinca major (Apocynaceae)View study →}. Its close relative, lesser periwinkle, is rated unsafe to take by mouth: it can cause nausea, vomiting, and nerve, kidney and liver damage ^{22Reference 22Therapeutic Research Center (n.d.)ReviewPeriwinkle (Vinca minor) — side effects, blood-pressure precautions and interactions — Natural Medicines consumer monographView study →}. Long-term therapeutic use is avoided. The plant is poisonous to sheep, cattle and horses if eaten, although it is not a frequent cause of livestock poisoning ^{20Reference 20Weeds Australia (n.d.)Blue periwinkle (Vinca major) — weed profile: origin, impacts and toxicity to livestockView study →}.

Chronic use. In a cell-line screen, V. major extract showed toxicity that “raises concern for chronic use” ^{9Reference 9van de Venter et al. · 2008Antidiabetic screening and scoring of 11 plants traditionally used in South Africa — in-vitro cell-line studyView study →}.

Blood pressure. Lesser periwinkle can lower blood pressure, and large amounts can drop it very low ^{22Reference 22Therapeutic Research Center (n.d.)ReviewPeriwinkle (Vinca minor) — side effects, blood-pressure precautions and interactions — Natural Medicines consumer monographView study →}. Vinpocetine, the drug made from its alkaloid vincamine, can cause brief changes in blood pressure, including falls ^{23Reference 23Petric et al. · 2023ReviewClinical pharmacology of vinpocetine: properties revisited and introduction of a population pharmacokinetic model for its metabolite, apovincaminic acid (AVA) — reviewView study →}. Avoid the plant and the concentrated alkaloids with low blood pressure, alongside blood-pressure medicines, and before surgery.

Interactions. No interaction study has been done on the whole herb.

References

1. Janot, M. M., & Le Men, J. (1954). Vinca major L. alkaloids: presence of reserpinine — phytochemical study. Comptes Rendus Hebdomadaires des Séances de l’Académie des Sciences, 238(26), 2550–2552. https://pubmed.ncbi.nlm.nih.gov/13199943/
2. Farnsworth, N. R., Fong, H. H., Blomster, R. N., et al. (1962). Studies on Vinca major (Apocynaceae). II. Phytochemical investigation. Journal of Pharmaceutical Sciences, 51, 217–224. https://doi.org/10.1002/jps.2600510307
3. Szatmári, S. Z., & Whitehouse, P. J. (2003). Vinpocetine for cognitive impairment and dementia — Cochrane systematic review and meta-analysis. Cochrane Database of Systematic Reviews, CD003119. https://pubmed.ncbi.nlm.nih.gov/12535455/
4. Bahadori, F., et al. (2012). Indole alkaloids from Vinca major and V. minor growing in Turkey — antioxidant and anticholinesterase activity. Natural Product Communications, 7(6), 731–734. https://pubmed.ncbi.nlm.nih.gov/22816294/
5. Fischhof, P. K., et al. (1996). Therapeutic efficacy of vincamine in dementia — randomised placebo-controlled trial. Neuropsychobiology, 34(1), 29–35. https://pubmed.ncbi.nlm.nih.gov/8884757/
6. Cheng, G. G., Zhao, H. Y., Liu, L., et al. (2016). Non-alkaloid constituents of Vinca major — a new iridoid glycoside with DPPH antioxidant activity. Chinese Journal of Natural Medicines, 14(1), 56–60. https://pubmed.ncbi.nlm.nih.gov/26850347/
7. Sari, S., Barut, B., Özel, A., & Şöhretoğlu, D. (2019). Tyrosinase inhibitory effects of Vinca major and its secondary metabolites — enzyme kinetics and in-silico model. Bioorganic Chemistry, 92, 103259. https://doi.org/10.1016/j.bioorg.2019.103259
8. Rauf, A., Bawazeer, S., Naseer, M., et al. (2021). In-vitro α-glycosidase and urease enzyme inhibition profile of some selected medicinal plants of Pakistan. Natural Product Research, 35(23), 5434–5439. https://doi.org/10.1080/14786419.2020.1779264
9. van de Venter, M., et al. (2008). Antidiabetic screening and scoring of 11 plants traditionally used in South Africa — in-vitro cell-line study. Journal of Ethnopharmacology, 119(1), 81–86. https://pubmed.ncbi.nlm.nih.gov/18588966/
10. Zhang, Z. J., Du, R. N., He, J., et al. (2016). Three new monoterpenoid indole alkaloids from Vinca major — cytotoxicity screen. Journal of Asian Natural Products Research, 18(4), 328–333. https://doi.org/10.1080/10286020.2015.1094463
11. Wei, Khan, Song, et al. (2017). Three new pyridine alkaloids from Vinca major cultivated in Pakistan — cytotoxicity screen (inactive). Natural Products and Bioprospecting, 7(4), 323–327. https://doi.org/10.1007/s13659-017-0137-7
12. Sawangjit, Chuenchom, Sanverm, et al. (2023). Efficacy and safety of herbal medicine on dementia and cognitive function — umbrella review of systematic reviews and meta-analyses. Phytotherapy Research, 37(4). https://doi.org/10.1002/ptr.7759
13. Zhang, Li, Yan, et al. (2018). An update on vinpocetine: new discoveries and clinical implications — review. European Journal of Pharmacology, 819, 88–95. https://doi.org/10.1016/j.ejphar.2017.11.041
14. Grieve, M. (1931). Periwinkles — Greater periwinkle (Vinca major): uses as an astringent and tonic — herbal reference. A Modern Herbal. https://botanical.com/botanical/mgmh/p/periwi27.html
15. Kumar, S., Singh, B., & Singh, R. (2022). Catharanthus roseus (L.) G. Don: a review of its ethnobotany, phytochemistry, ethnopharmacology and toxicities — review. Journal of Ethnopharmacology, 284, 114647. https://pubmed.ncbi.nlm.nih.gov/34562562/
16. Fishbein, M., Lemke, D. E., & Krings, A. (n.d.). Vinca major — species description, flowering and North American distribution. In Flora of North America, Vol. 14 (Apocynaceae). eFloras. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=200018490
17. Li, B., Leeuwenberg, A. J. M., & Middleton, D. J. (n.d.). Vinca major — species description. In Flora of China, Vol. 16 (Apocynaceae). eFloras. http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=200018490
18. Nazimuddin, S., & Qaiser, M. (n.d.). Vinca major — species description and distribution. In Flora of Pakistan (Apocynaceae). eFloras. http://www.efloras.org/florataxon.aspx?flora_id=5&taxon_id=200018490
19. NC State Extension (n.d.). Vinca major — description, native range, invasive status and identification — species database. North Carolina Extension Gardener Plant Toolbox. https://plants.ces.ncsu.edu/plants/vinca-major/
20. Weeds Australia (n.d.). Blue periwinkle (Vinca major) — weed profile: origin, impacts and toxicity to livestock. Centre for Invasive Species Solutions. https://weeds.org.au/profiles/blue-periwinkle-vinca/
21. New Zealand Plant Conservation Network (n.d.). Vinca major — naturalisation and environmental weed status. https://www.nzpcn.org.nz/flora/species/vinca-major/
22. Therapeutic Research Center (n.d.). Periwinkle (Vinca minor) — side effects, blood-pressure precautions and interactions — Natural Medicines consumer monograph. RxList. https://www.rxlist.com/supplements/periwinkle.htm
23. Petric, Z., Paixão, P., Filipe, A., & Guimarães Morais, J. (2023). Clinical pharmacology of vinpocetine: properties revisited and introduction of a population pharmacokinetic model for its metabolite, apovincaminic acid (AVA) — review. Pharmaceutics, 15, 2502. https://pubmed.ncbi.nlm.nih.gov/37896263/

View all 23 references▾