Cynara-SL (Cynara scolymus)
Lead author: Neeta O'Mara, Pharm.D., BCPS
What It Is
The artichoke is one of the oldest medicinal plants. Ancient Egyptian drawings involving fertility and sacrifice often depicted the artichoke, and the ancient Greeks and Romans used artichokes as a digestive aid.1,2 Cynara-SL is a new over-the-counter dietary supplement made from dried extract of the leaves of global artichoke (Cynara scolymus).3How It Works
Artichoke contains a substance, cynarine, which is considered a choleretic.1,3,4 High-dose extracts of artichoke leaves have been shown to increase bile secretion by up to 150%.2,3,5 This is thought to improve dyspeptic symptoms such as irritable stomach or colon, bloating, flatulence, and constipation or diarrhea.5,6 Additionally, some studies show that artichoke preparations decrease serum cholesterol.1,5 However, not all studies show this beneficial effect.1 In animal studies, artichoke leaf extract preparations reduce cholesterol synthesis by a variety of mechanisms including inhibition of the enzyme HMG-CoA reductase.2,5,6 It is thought that the HMG-CoA effects are mediated by luteolin, a flavonoid found in the artichoke.5,6 Finally, hepatoprotective effects including an increase in tissue regeneration, intrahepatic increases in perfusion, an increased number of bionucleate hepatocytes and RNA content, and stimulation of cell division with artichoke extract preparations have been noted in in vitro studies.5,6 This, too, is thought to be due to the cynarine component of artichokes.1,5Indications
Under the Dietary Supplement Health Education Act of 1994, claims can be made for the health benefits of dietary supplements as long as they do not claim to diagnose, prevent, mitigate, treat or cure a specific disease. Thus, the manufacturer of Cynara-SL claim that it "aids in digestion, providing fast, immediate symptomatic relief from dyspeptic symptoms including vomiting, nausea, abdominal pain, constipation, and flatulence."3 It is touted to work within 15-20 minutes. Additionally, they state that it "protects the liver from toxin damage" and "it may be useful in maintaining normal cholesterol levels."3 According to the Commission E Monographs of the German Ministry of Health, artichoke is a "choleretic" for "dyspeptic problems."4How Supplied
Each capsule of Cynara-SL contains 320 mg dried extract from artichoke leaves, extracted with water. It is available in boxes with 30 capsules in a blister pack. According to the manufacturer, the cost of 30 capsules is $10.99.3Dosage
According to the manufacturer, Cynara-SL can be taken as part of the everyday diet or as needed. The recommended dose of Cynara-SL for long-term use to help maintain a healthy liver and digestive system is one to two capsules daily. As a nutritional supplement, one to two capsules may be taken shortly before or after eating or drinking too much. The capsules should not be chewed, but instead be swallowed intact with a cool liquid. The maximum dose per day is six capsules.3Adverse Effects
According to the product information and the Commission E Monographs of the German Ministry of Health, there are no known side effects.3,4 However, other references state that contact dermatitis has been reported.1,5Drug Interactions
There are no known drug interactions.3,4
Contraindications
Cynara-SL is contraindicated in patients who are allergic to artichoke.3,4 Patients allergic to the Compositae family (ie, chrysanthemum, marigold, daisy, ragweed) may develop allergic reactions to artichoke. Cynara-SL should not be used in patients who have occlusion of biliary ducts or gallstones.3-5 Increasing bile flow can irritate blocked biliary ducts.
Use In Pregnancy
The manufacturer recommends that pregnant women seek advice from their health professional before using Cynara-SL.3 There is not enough reliable information about the use of therapeutic doses of artichoke leaf extract during pregnancy or lactation. Avoid using in amounts greater than those consumed in food.7Manufacturer
Lichtwer Pharma, 2 Industrial Way West, Meridian Center 1, Eatontown, NJ 07724;phone 800-837-3203.
Commentary
As with many dietary supplements, clinical trials supporting the use of Cynara-SL in humans are limited. The manufacturer cites two clinical trials that show improvement in bile flow and blood lipid levels and two post-marketing studies in patients with dyspeptic symptoms, but does not provide specific references.3 No literature is cited to support the beneficial hepatic effects. The majority of the studies in the literature are in vitro studies making it difficult to draw conclusions on the clinical efficacy or toxicity.
The most well studied claim, relief of dyspepsia, has been evaluated in three recent studies involving a total of 1030 patients. Symptomatic relief of "dyspeptic symptoms" occurred in 50-92% of patients.5,6One reference compares artichoke extract preparations to milk thistle in terms of an "herbal liver remedy and detoxification enhancer."6 Both artichoke and milk thistle are part of the Compositae family.1,6 Additionally, the active components, cynarin and silymarin, for artichoke and milk thistle, respectively are similar.6 Both are thought to have antioxidant effects.1 Some authors feel that milk thistle may be better for liver dysfunction due to viral hepatitis while artichoke extract preparations are better "as a general tonic to improve liver function and detoxification."6
Until larger, more well-controlled studies are available, artichoke extract preparations can be considered "possibly effective" for dyspeptic symptoms.7 Not enough information is known about the other claims.
References- Anon. Artichoke. Lawrence Review of Natural Products. St. Louis: Facts & Comparisons, 1999.
- Artichoke (Cynara scolymus). Healthnotes Online. www.healthzone.com/healthnotes/Herb/Artichoke.htm. Accessed 6/5/00.
- Lichtwer Pharma. Cynara-SL (Cynara scolymus) product information. Eatontown, NJ.
- Blumenthal M, et al. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
- Kraft K. Artichoke leaf extract-Recent findings reflecting effects on lipid metabolism, liver and gastrointestinal tracts. Phytomedicine 1997;4:369-78.
- Artichoke extracts: Improves digestion, liver function, and cholesterol levels. From: Natural Medicine Online. http://www.nat-med.com/archives/artichoke.htm. Accessed 6/14/00.
- Jellin JM, Batz F, Hitchens K, eds. Pharmacist's Letter / Prescriber's Letter Natural Medicines Comprehensive Database. Stockton, CA: Therapeutic Research Faculty; 2000. www.naturaldatabase.com
July, 2000