When it comes to medicinal uses, Japanese honeysuckle vine (Ren Dong Teng in mandarin) seems not as high-profile as honeysuckle flower (Jin Yin Hua). But initially the medicinal part was not flowers but stems, according to the Ming Yi Bie Lu (Miscellaneous Records of Famous Physicians), an ancient medical book written around 520 A.D. and compiled by Tao Hongjing. And there it was rated as one of the top-grade herbs. In addition, Li Shizhen also commented in Ben Cao Gang Mu (Compendium of Materia Medica) that the stem, leaf, and flower of honeysuckle are with the same healing properties. However, today honeysuckle vines and honeysuckle flowers are used separately as two different herbs. The former one is good at treating rheumatic diseases since it can dispel wind and remove obstruction in the meridians while the latter is specialized at healing infectious diseases because it can clear away heat and toxic materials.
What is honeysuckle vine?
Medicinally it mainly refers to the dried stems with leaves of Lonicera japonica Thunb., which is one of flowering vines in the family caprifoliaceae. But sometimes it also means other honeysuckle vine varieties – L. confusa (Sweet) DC., L. hypoglauca Miq., or L.fuluotomentosa Hsu et S.C.Chneg. Hence, it is also known as Caulis Lonicerae in Latin name. It is usually reaped in autumn and winter. And following steps are to remove the impurities, bind them in bundles or roll into a group, and dry in the sun.
Climbing honeysuckle vine is usually cultivated as ground cover and for landscaping purpose. Since they attract bees, they will add color and bring in life to the garden. Honeysuckle plants are a semi-evergreen, perennial shrub with twining stems. It is up to 9 meters in length. Stems are hollow. Young shoots are densely pubescent. Leaves are opposite, densely pubescent, and with oval or ovate blade, mucronate or rarely obtuse apex, rounded or nearly heart-shaped base, entire margin, and pubescent sides and edges. Flowers are in pair, and axillary; pedicels are densely pubescent; bracteole is about 1mm; short calyx is with remnant leaf or leaf scars. The dried one is brittle, easily broken, and with hollow and yellow-white section. It is odorless and slightly bitter in old branches or tasteless in twigs. Bloom time is from May to July and fruiting time is from July to October.
Honeysuckle vine leaves contain lonicerin (luteolin-7-rhamnoglucoside), luteolin-7-O-digalactoside, luteolin, loniceraflavone, caffeic acid, vanillic acid, venoterpine, etc. Young branches contain secoxyloganin. And aerial parts mainly contain chlorogenic acid, isochlorogenic acid, loganin, secologanin dimethylacetal, vogeloside, epivogeloside, alkaloids, tannins, and trace elements like iron, barium, manganese, zinc, titanium, strontium, copper, etc.
Honeysuckle vine health benefits
Fresh or dried honeysuckle vine can be used for a variety of complaints clinically, especially eczema in babies, arthritis and rheumatism, cough, and more.
Eczema in babies is a common skin condition and it is hard to relieve although steroid ointment or cream, as well as an emollient have been applied according to the advice from doctors. In this case, bathing with honeysuckle decoction can be a good remedy, which will completely eradicate eczema over time. More importantly, it won’t harm the baby’s skin. However, it works mainly for baby eczema caused by milk. But for older kids, it is not suitable since the causes are more complex.
It is also a drug commonly used to treat arthritis. Clinically it has a certain effect on reactive arthritis, rheumatoid arthritis, osteoarthritis, cervical spondylosis pain, gouty arthritis, etc. Even more important, it is of cold in nature and with no side effects, which is quite rare and commendable among so many herbs of dispelling wind and removing obstruction in the meridians. In addition, honeysuckle-based herbal recipes works for joint and muscle aches in diseases like lupus erythematosus, Sjogren’s syndrome, and dermatomyositis.
Flavonoids like galuteolin and luteolin have a better therapeutic effect on chronic bronchitis. And honeysuckle happens to contain these two ingredients. As a result, it is antitussive and expectorant too. Generally honeysuckle alone is not used for chronic cough. But when used it in combination with other herbs, it can play important roles in the treatment of immune disease accompanied with interstitial pneumonia, secondary infection, and chronic cough.
Modern pharmacological actions of honeysuckle vines
1) It has significant anti-inflammatory activity. The intramuscular injections can significantly inhibit paw swelling and pleural effusion in rat. Luteolin orally can result in thymic atrophy in young rat. It indicates that luteolin can enhance the function of the adrenal cortex, which is believed to be the reason why it reduces inflammation;
2) It has obvious inhibition on type I hypersensitivity (or immediate hypersensitivity);
3) Luteolin can relieve spasms on isolated small intestine of rabbits and ileum and tracheal smooth muscle of guinea pig;
4) Low concentrations can inhibit the isolated heart while high concentrations can excite guinea pig heart, increase contraction, and accelerate the heart rate;
5) Gavage or intravenous injection has significant antihypertensive effect on anesthetized cats. Large doses can reduce up to shock level and higher doses can make the cat die due to shock. The antihypertensive mechanism is related to nerve center and direct angiectasis;
6) It has significant lipid-lowering effect;
7) It has an antibacterial effect;
8) It has antitussive, expectorant, and anti-asthma effects;
9) It has mild diuretic effect, which can increase sodium excretion;
10) Luteolin in vitro can inhibit the growth of NK/Ly ascites tumor cells.
Sample honeysuckle stem recipes on herbal remedies
The Chinese Materia Medica tends to think that it is sweet in flavor and cold in nature. It covers meridians of heart and lung. Normal functions are clearing heat, removing toxicity, and dredging collaterals. Common honeysuckle vine uses and indications include fever in febrile disease, boils and carbuncles, heat-toxicity induced dysentery with bloody stool, and wind-damp-heat rheumatism. Recommended dosage is from 10 to 30 grams in decoction. In addition, it is also used in pills, powder, or soaked wine.
1) Shen Xiao Tuo Li San from Tai Ping Hui Min He Ji Ju Fang (Formulas of the Peaceful Benevolent Dispensary). It is combined with Huang Qi (Astragalus Root), Dang Gui (Dong Quai), and Gan Cao (Licorice Root) to treat carbuncle on the back, appendicitis, acute mastitis, swelling of unknown origin, etc.
2) Ren Dong Jiu from Wai Ke Jing Yao (Essence of Diagnosis and Treatment of External Diseases). It is coupled with Licorice to cure all deep-rooted carbuncles.
3) Ren Dong Gao from Qian Kun Sheng Yi Mi Yun. It is formulated with Xi Tie Shi (magnet), sesame oil, and Huang Dan (yellow lead) to heal all sorts of pain, metal-inflicted wound, and malignant sores.
4) Ren Dong Teng Tang from HONG BAN LANG CHUANG ZHONG YI LIN CHUANG YAN JIU (Lupus Erythematosus Medicine Clinical Research). It is matched with Gang Ren Gen (Downy Rose Myrtle Root), Hu Zhang (Japanese Knotweed), Chuan Niu Xi (Cyathula Root), and Licorice to treat various rheumatic diseases.
Honeysuckle vine side effects and contraindications
Honeysuckle vine is considered non-toxic by the Compendium of Materia Medica. The toxicological test shows that the LD50 is 10mg/kg in intraperitoneal injection to mice. In addition, after forcibly fed with 50 times of the adult dose of luteolin for continuous 20 days, guinea pigs showed no abnormity on general activity, liver and kidney function, blood, and vital organs. Both the above animal experiments showed that the toxicity of luteolin is really low. So far there are no adverse reactions found in the conventional dose, long-term use, or high dose (30 to 60 grams). TCM wise, it shouldn’t be used in cases of deficiency-cold in spleen and stomach and diarrhea because of the cold nature.