Japanese Honeysuckle: An Antiviral Immune Booster That Combats COVID-19

Researchers discovering that Chinese medicine was right about healing effects of this fragrant anti-inflammatory plant

Japanese Honeysuckle YI-LIN TSAI/Shutterstock

The smell of honeysuckle is almost intoxicating. Its sweet vanilla-like aroma makes you stop, close your eyes, and breathe deep. Although many of us may be familiar with honeysuckle’s sweet-smelling flowers, not all of us may be aware that it also has powerful healing capabilities.

Honeysuckle includes about 200 species that grow worldwide. All species of honeysuckle belong to the genus Lonicera and the family Caprifoliaceae; they grow primarily in temperate regions and are native to Southeast Asia. In the temperate regions of the United States, they generally produce their fragrant flowers from late spring through early fall.

Honeysuckle, which is popular throughout Asia, was reportedly brought to the United States from Japan as an ornamental in the early 1800s. It has thrived, and is now considered an invasive species.

Honeysuckle is known not only for its beauty and sweet smelling flowers, but also for its abundant healing properties. The species commonly used in medicine and Chinese medicine in particular, is Japanese honeysuckle, or Lonicera japonica, which comes from eastern Asia.

Japanese honeysuckle is also known as the golden and silver honeysuckle because its flowers open white and within a few days fade to yellow, creating a beautiful mix of white and yellow flowers resembling gold and silver.

Different parts of the honeysuckle plant treat various health conditions, although the flowers and stems are the parts most often used in medicines.

Japanese Honeysuckle in Chinese Medicine

Chinese medicine has used Japanese honeysuckle for healing purposes for thousands of years. In China, it’s known as”jin yin hua.” The flower is considered cold; its flavor is sweet, and it’s in a class of herbs that clear heat and remove toxins. Jin yin hua explicitly targets the lungs, stomach, and large intestine.

In Eastern medicine theory, toxic heat is responsible for many bacterial and viral infections, high fevers, skin conditions that are red, swollen and painful, and many bleeding disorders. Toxic heat is considered heat that has progressed to a more severe stage, so jin yin hua is very helpful in treating a host of conditions with toxic heat as their cause.

Jin yin hua is used in Chinese medicine to treat a wide variety of conditions that include:

• Viral infections (considered toxic heat in Chinese medicine) such as mumps and encephalitis (inflammation of the brain)
• Upper respiratory tract infections, cough, sore throat, fevers and pneumonia
• Digestive disorders such as ulcers and dysenteric infections (an infection of the intestines causing diarrhea with pus or blood)
• Skin infections like carbuncles, breast abscesses, and mastitis when used externally as a poultice

In Eastern medicine, different parts of the Japanese honeysuckle plant are used depending on the condition, and their preparation varies depending on the severity of the disease and the constitution of the patient.

For example, herbs are always used with caution with children and the elderly, since their bodies are not as strong as those of adults. Children are still developing and have sensitive digestive systems. Often elderly patients have different health conditions and may be on medications, so using herbs that are gentle on the body is advised. Of course, each patient is evaluated individually, but these are some general rules of thumb when it comes to herbal medicine.

The parts of the Japanese honeysuckle plant used in Chinese medicine are:

• Charred honeysuckle flower (dry-fried or baked at high temperature until scorched). This method allows the herb to penetrate deeply into the body, to the blood level.
• Honeysuckle flower dew is a fluid distilled from the flowers. This preparation method is considered more gentle on the stomach and is the preferred use for children’s conditions.
• Honeysuckle fruit is used with caution as most honeysuckle berries are toxic.

Chinese herbal medicine also is playing an important role in treating COVID-19. Japanese honeysuckle’s abilities to treat viral infections and infections of the upper respiratory tract are well documented, and researchers in China are working it into their long-term treatment strategies. Studies have shown that Japanese honeysuckle has been used in response to COVID-19 and has effectively reduced the incidence of severe or critical events, improved clinical recovery, and helped alleviate symptoms such as cough and fever.

In another study, published in the journal Cell Discovery, researchers have discovered that a decoction or tea made from Japanese honeysuckle can directly target SARS-CoV-2 genes and inhibit viral replication. The same study also confirms that honeysuckle decoction is able to suppress SARS-CoV-2 infection. These findings are hopeful as they give us more options in dealing with the virus.

The Science of Japanese Honeysuckle

Research has discovered that Japanese honeysuckle has antiviral, antibacterial, antiseptic, anti-inflammatory, antioxidant, and hepatoprotective properties (which protect the liver from damage). It has also been shown to lower blood lipid levels and have a normalizing effect on blood pressure. Science is only now beginning to discover the range of Japanese honeysuckle’s healing capabilities, but is affirming what Eastern medicine has known for millennia–that Japanese honeysuckle is powerful medicine.

Below are just a few examples of how research-backed insight into Japanese honeysuckle’s healing potential.

Anti-Inflammatory

Inflammation is at the root of many of today’s most pernicious diseases such as arteriosclerosis, cancer, diabetes, and Alzheimer’s disease. Science is discovering that many herbal medicines have robust anti-inflammatory actions and is beginning to study them in the hope they can be used to treat many of our modern diseases.

Honeysuckle is showing some promise and could someday be used in the treatment of cancer, and studies demonstrating its extensive anti-oxidant and anti-inflammatory actions may help to reduce your cancer risk.

Antiviral and Immune Booster

Japanese honeysuckle is known as a potent antiviral, and is used in Eastern medicine to treat viral infections and boost the immune system. In a 2018 study, honeysuckle berries were shown to boost the immune systems of immunocompromised mice where they acted as an immunomodulatory agent and significantly increased activity of natural killer cell activity. Natural killer cells are a type of white blood cell that act to kill viruses and tumor cells.

Diabetes

There are also some promising findings that suggest this herb may be useful in treating diabetes, a disease that affects one in 9 Americans, a staggering 37 million people or 11.3 percent of the population. A 2015 study found Japanese honeysuckle’s anti-inflammatory and antioxidant properties have anti-diabetic effects. After four weeks of taking Japanese honeysuckle (Lonicera japonica) orally, rats with Type 2 diabetes had reduced their blood glucose levels and improved insulin resistance.

In another study, published in the journal Planta Medica, the anti-inflammatory properties of Japanese honeysuckle were shown to reduce diabetic neuropathy. In fact, after eight weeks of oral treatment the rats in the study showed improvement in all their diabetes-induced abnormalities. The study concluded that Japanese honeysuckle is able to inhibit the inflammatory response and halt the progression of diabetic neuropathy.

Contraindications

There are a few things to consider if you are interested in using Japanese honeysuckle for medicinal purposes. It is always advisable to do so under the direction of a health care practitioner or qualified herbalist. Here is a list of things to be aware of.

1. Bleeding: Japanese honeysuckle can thin blood and slow blood clotting, so be careful if you are on blood thinning medication and avoid it if you are planning to have any surgical procedures.
2. Berry Toxicity: The berries of many of the honeysuckle species are toxic and can cause gastrointestinal issues, so their ingestion isn’t recommended.
3. Pregnancy and Breastfeeding: Since Japanese honeysuckle is in a class of herbs that in Chinese medicine are considered very moving and have a dispersing action, they should be avoided if pregnant or breastfeeding.
4. Poisonous for Dogs: Every part of the honeysuckle plant is highly toxic to dogs. They are attracted, like we are, to the fragrant flowers.

Final Thoughts

Japanese honeysuckle is both a beautiful plant and powerful medicine. Its well-documented use in Eastern medicine provides us with a wealth of information about its healing properties that, thankfully, science is now beginning to explore for treating a variety of conditions and diseases. Perhaps in the not-so-distant future, Japanese honeysuckle will move from our gardens to our medicine cabinets.