Organic Periwinkle
Also known as: Madagascar periwinkle, rosy periwinkle, Organic Periwinkle, Catharanthus roseus
Overview
Catharanthus roseus, commonly known as Madagascar periwinkle or rosy periwinkle, is a tropical plant native to Madagascar. It is primarily recognized as the natural source of potent anticancer alkaloids, vinblastine and vincristine, which are extensively used in chemotherapy for various cancers, including childhood acute lymphoblastic leukemia (ALL) and Hodgkin’s lymphoma. While the plant's extracts have been explored for other potential benefits such as anti-inflammatory, antioxidant, and neuroprotective effects, the scientific evidence for these applications is limited and preliminary. The research maturity for its anticancer alkaloids is very high, with decades of clinical use and extensive biochemical characterization, making them standard-of-care drugs. However, oral consumption of unstandardized C. roseus extracts as a supplement is considered unsafe due to significant toxicity risks.
Benefits
The primary and most significant benefits of Catharanthus roseus are derived from its isolated alkaloids, vinblastine and vincristine, which are established chemotherapeutic agents. These compounds effectively treat various cancers, including ALL, Hodgkin’s disease, breast, bladder, lung, and testicular cancers, by inhibiting cell division. Their efficacy is clinically significant and supported by decades of rigorous clinical trials, making them standard-of-care treatments for specific cancer types. Preclinical studies have also indicated secondary benefits from C. roseus extracts, such as antioxidant and protective effects against heavy metal toxicity (e.g., cadmium-induced toxicity), likely due to the presence of polyphenols and flavonoids. These effects have been observed in animal models, reducing oxidative stress and tissue injury. However, these secondary benefits are not clinically established for human use, and oral supplementation with raw extracts is not recommended due to safety concerns.
How it works
The primary mechanism of action for the therapeutic compounds derived from Catharanthus roseus, namely vinblastine and vincristine, involves their role as mitotic inhibitors. These alkaloids bind to tubulin, a protein essential for the formation of microtubules. By preventing microtubule polymerization, they disrupt the assembly of the mitotic spindle, thereby arresting cell division at the metaphase stage. This leads to the induction of apoptosis (programmed cell death) in rapidly dividing cancer cells. In addition to these specific alkaloids, other bioactive compounds found in C. roseus extracts, such as polyphenols and flavonoids, exhibit antioxidant activity. They scavenge reactive oxygen species, thereby protecting cells from oxidative damage. However, the anticancer alkaloids are administered intravenously in clinical settings due to their poor oral bioavailability and significant toxicity concerns.
Side effects
Oral consumption of unstandardized Catharanthus roseus extracts as a supplement is considered unsafe and can lead to serious adverse effects. These include nausea, vomiting, nerve damage (neurotoxicity), kidney damage, liver damage, and dangerously low blood pressure. The pharmaceutical derivatives, vincristine and vinblastine, when used in chemotherapy, also have significant side effects, including neurotoxicity (e.g., peripheral neuropathy, constipation), gastrointestinal symptoms, and bone marrow suppression. Specific risk factors for toxicity include pre-existing liver or kidney impairment. Vincristine and vinblastine interact with other chemotherapeutics and drugs metabolized by CYP450 enzymes, which can alter their metabolism and increase toxicity. Contraindications for these drugs include pregnancy, breastfeeding, and severe liver dysfunction. Vinpocetine, a synthetic derivative related to periwinkle alkaloids, may cause anxiety, headache, and dizziness, and is contraindicated in pregnancy and bleeding disorders. Due to the severe toxicity profile, C. roseus should not be consumed as an oral supplement.
Dosage
There is no established safe or effective oral dosing for Catharanthus roseus extracts as a dietary supplement due to its significant toxicity. The potent anticancer alkaloids, vincristine and vinblastine, are strictly administered intravenously in clinical oncology settings under medical supervision. Dosage is typically calculated based on body surface area (e.g., vincristine 1.4 mg/m² weekly) and is part of complex chemotherapy protocols. The timing and administration are precisely controlled by healthcare professionals. These alkaloids have poor oral bioavailability, necessitating parenteral administration for therapeutic efficacy. There are no established cofactors for supplement use, and any use of C. roseus derivatives requires rigorous clinical monitoring due to their narrow therapeutic index and severe side effects. Self-medication with any form of periwinkle is strongly discouraged.
FAQs
Is organic periwinkle safe as a supplement?
No, oral use of unstandardized periwinkle extracts is considered unsafe and can cause serious side effects, including nerve, kidney, and liver damage, and dangerously low blood pressure.
Does periwinkle improve memory or blood pressure?
There is insufficient scientific evidence to support these uses for C. roseus extracts, and significant safety concerns limit any recommendation for such purposes.
What is the difference between periwinkle and vinpocetine?
Vinpocetine is a synthetic derivative, often used for cognitive disorders, but it is not the same as raw periwinkle extract and also carries its own safety warnings and contraindications.
Are the anticancer compounds available in supplements?
No, vincristine and vinblastine are pharmaceutical drugs derived from periwinkle, not available as dietary supplements, and are administered under strict medical supervision for cancer treatment.
Research Sources
- https://onlinelibrary.wiley.com/doi/full/10.1002/pbc.31247 – This research details the discovery and clinical use of vincristine and vinblastine from Catharanthus roseus. It emphasizes their mechanism as mitotic inhibitors and their critical role in chemotherapy protocols for childhood acute lymphoblastic leukemia (ALL) and other cancers, highlighting their established efficacy.
- https://www.webmd.com/vitamins/ai/ingredientmono-476/periwinkle – This source indicates that oral periwinkle supplements are unsafe and can cause serious side effects such as nausea, vomiting, nerve, kidney, and liver damage, and dangerously low blood pressure. It also states there is insufficient evidence to support claims for memory improvement or blood pressure lowering.
- https://pmc.ncbi.nlm.nih.gov/articles/PMC10957771/ – This preclinical study demonstrated that Catharanthus roseus extract has protective antioxidant effects against cadmium-induced kidney and liver damage in animal models. It showed a reduction in oxidative stress markers and tissue injury, though it notes the limitation of lacking human trials.
- https://www.webmd.com/vitamins/ai/ingredientmono-175/vinpocetine – This article describes vinpocetine as a synthetic derivative related to periwinkle alkaloids, used for cognitive disorders. It notes potential side effects like anxiety, headache, and dizziness, and contraindications for pregnancy and bleeding disorders, distinguishing it from raw periwinkle extract.
- https://pubmed.ncbi.nlm.nih.gov/38651238/ – This systematic review highlights the diverse pharmacological effects of Catharanthus roseus phytochemicals, including anticancer, anti-inflammatory, and antimicrobial activities. It confirms the established role of vincristine and vinblastine in cancer treatment and notes antioxidant properties of extracts, while calling for more clinical trials on non-oncology uses.
- https://lemur.duke.edu/milestone-research-on-madagascar-periwinkle-uncovers-pathway-to-cancer-fighting-drugs/ – This source provides historical context on the milestone research that led to the discovery of cancer-fighting drugs from Madagascar periwinkle. It underscores the plant's significance as the origin of vinblastine and vincristine, crucial in modern chemotherapy.
