Corydalis turtschaninovii, Corydalis yanhusuo
NOTE: We recommend against using this herb at all.
Widely used in Chinese herbal medicine, the herb corydalis is said to alleviate pain by “moving qi” and “stimulating the blood.” These expressions refer to traditional concepts included within the complex theories of traditional Chinese herbal medicine. In terms of Western diagnostic categories, corydalis may be recommended for soft tissue injuries, menstrual discomfort, and abdominal pain.
The part of the plant used medicinally is the rhizome (underground stalk).
There is no reliable evidence that corydalis or its constituents offer any medicinal benefits. Corydalis contains a number of active and potentially dangerous chemicals in the alkaloid family, including tetrahydropalmatine (THP), corydaline, protopine, tetrahydrocoptisine, tetrahydrocolumbamine, and corybulbine. Of these, THP may be the most active, as well as the most toxic (see Safety Issues).
Only double-blind, placebo-controlled studies can actually show that a treatment works, and there is only one such study that is relevant to corydalis. This trial tested THP as a treatment for a type of heart rhythm abnormality called supraventricular arrhythmia.1 Reportedly, use of THP produced significant benefits as compared to placebo. However, this study was conducted in China, and there is considerable skepticism about the validity of Chinese medical trials.2 (For information on why double-blind studies are essential, see Why Does This Database Rely on Double-blind Trials?)
Much weaker evidence from animal and test-tube studies hint that TNP or corydalis extracts might have pain-relieving, sedative, and anti-inflammatory effects.3-5 Corydalis constituents may also affect neurotransmitters in the brain, including dopamine and GABA.6-7 Equally weak evidence hints at benefits for preventing or treating cataracts,8 reducing blood coagulation,9 and lowering blood pressure.10 However, none of this research remotely approaches the level of evidence that can prove a treatment effective.
Corydalis is usually taken at a dose of 5–10 grams daily, or equivalent quantities of an extract.
Corydalis has not undergone any meaningful safety testing. The herb is known to produce immediate side effects, including nausea and fatigue, in some people. In addition, there are serious safety concerns related to its alkaloid constituent THP. Use of products containing THP has repeatedly been associated with severe and potentially fatal liver injury.11-16
In addition, there are three reports that use of THP by young children has led to life-threatening suppression of the central nervous system.17
For these reasons, we strongly recommend against the use of corydalis, especially by young children, pregnant or nursing women, or people with liver disease.
1. Xiaolin N, Zhenhua H, Xin M, et al. Clinical and experimental study of dl-tetrahydropalmatine effect in the treatment of supraventricular arrhythmia. J Xi’An Med Univ. 1998;10:150–3.
2. Vickers A, Goyal N, Harland R, et al. Do certain countries produce only positive results? A systematic review of controlled trials. Control Clin Trials. 1998;19:159–66.
3. Reimeier C, Schneider I, Schneider W, et al. Effects of ethanolic extracts from Eschscholtzia californica and Corydalis cava on dimerization and oxidation of enkephalins. Arzneimittelforschung. 1995;45:132–6.
4. Wei F, Zou S, Young A et al. Effects of four herbal extracts on adjuvant-induced inflammation and hyperalgesia in rats. J Altern Complement Med. 1999;5:429–36.
5. Schafer HL, Schafer H, Schneider W, et al. Sedative action of extract combinations of Eschscholtzia californica and Corydalis cava. Arzneimittelforschung. 1995;45:124–6.
6. Kleber E, Schneider W, Schafer HL, et al.. Modulation of key reactions of the catecholamine metabolism by extracts from Eschscholtzia californica and Corydalis cava. Arzneimittelforschung. 1995;45:127–31.
7. Chernevskaja NI, Krishtal OA, Valeyev AY. Inhibitions of the GABA-induced currents of rat neurons by the alkaloid isocoryne from the plant Corydalis pseudoadunca. Toxicon. 1990;28:727–30.
8. Kubo M, Matsuda H, Tokuoka K, et al. Studies of anti-cataract drugs from natural sources. I. Effects of a methanolic extract and the alkaloidal components from Corydalis tuber on in vitro aldose reductase activity. Biol Pharm Bull. 1994;17:458–9.
9. Xing JF, Wang MN, Ma XY, et al. Effects of dl-tetrahydropalmatine on rabbit platelet aggregation and experimental thrombosis in rats. Chin Pharm Bull. 1997;13:258–60.
10. Lin MT, Chueh FY, Hsieh MT, et al. Antihypertensive effects of dl-tetrahydropalmatine: an active principle isolated from corydalis. Clin Exper Pharm Physiol. 1996;23:738–42.
11. McRae CA, Agarwal K, Mutimer D et al. Hepatitis associated with Chinese herbs. Eur J Gastroenterol Hepatol. 2002;14:559–62.
12. Stickel F, Egerer G, Seitz HK. Hepatotoxicity of botanicals. Public Health Nutr. 2000;3:113–24.
13. Picciotto A, Campo N, Brizzolara R, et al. Chronic hepatitis induced by Jin Bu Huan. J Hepatol. 1998;28:165–7.
14. Horowitz RS, Feldhaus K, Dart RC, et al. The clinical spectrum of Jin Bu Huan toxicity. Arch Intern Med. 1996;156:899–903.
15. Kaptchuk TJ. Acute hepatitis associated with Jin Bu Huan. Ann Intern Med. 1995;122:636.
16. Woolf GM, Petrovic LM, Rojter SE, et al. Acute hepatitis associated with the Chinese herbal product Jin Bu Huan. Ann Intern Med. 1994;121:729–35.
17. Jin Bu Huan toxicity in children—Colorado, 1993. MMWR Morb Mortal Wkly Rep. 1993;42:633-6.
Last reviewed September 2014 by EBSCO CAM Review Board
Last Updated: 9/18/2014