Natural Herbs for Colds and Flu

1. Echinacea

Echinacea is an ancient herb used for its antibiotic property. It was used to treat fevers, syphilis, infections and blood poisoning.

There is a renewed interest in the medicinal benefits of echinacea recently especially in Germany and the United States. Studies confirmed that this herb can reduce inflammation, relieve pain and boost the immune system.

In addition, echinacea has antioxidant, antibacterial and antiviral properties.

The antiviral activity of echinacea blocks the replication of cold and influenza viruses. Furthermore, by boosting the immune system, echinacea activates the immune cells necessary to stop these viruses.

These medicinal effects make echinacea especially effective for treating respiratory tract infections such as cold and flu. In addition, echinacea is commonly used to treat common symptoms of cold and flu such as cough, runny nose, sore throat, and fever.

One study found that echinacea can lower the risk of the common cold by 60% and reduce the duration of sickness by 1 - 4 days.

The 3 species of echinacea used in herbal preparations are Echinacea pallida, Echinacea purpurea, and Echinacea angustifolia. Echinacea supplements are usually formulated with one, two or all of the different species.

These supplements are formulated as capsules, tablets, ointments, tinctures, and extracts.

Echinacea is safe and well-tolerated by most people. However, it can cause a numbing and tingling sensation on the tongue.

This herb should be avoided by those placed on immunosuppressants because of its immune-boosting effect. Furthermore, echinacea may trigger allergic reactions in people suffering from asthma or plant allergies.

2. Elderberry

Elderberry is another ancient herb that was used as a cure-all. It was used to treat wounds and fevers as well as detoxify the body.

Recent studies confirmed that elderberry was indeed effective in the treatment of cold and flu.

In those studies, its antiviral properties were effective against both influenza A and influenza B viruses. When compared to Tamiflu (the most common prescription drug used to treat flu), the elderberry achieved a cure in 2 – 3 days while it took 5 – 6 days for Tamiflu to get rid of flu symptoms.

Besides its antiviral properties, elderberry can also improve cold and flu symptoms by its antibacterial, antioxidant and anti-inflammatory properties.

Although there are different plants in the elderberry family, the one used in medicinal herbal preparations is Sambucus nigra. This is species is also known as black elder or European elder.

Most of the other elderberry species, especially Sambucus ebulus, can be toxic.

In addition, the unripe fruit, leaves, seeds, and bark of elderberry can be poisonous because they contain cyanide-based compounds. Therefore, make sure to choose a trusted product made from non-toxic elderberry extracts.

3. Astragalus

Astragalus is yet another ancient herb used in the treatment of colds and flu. It is a common ingredient of herbal preparations used to treat respiratory infections in Traditional Chinese Medicine.

As an antioxidant and an adaptogen, astragalus is used to protect the body against oxidative stress as well as physical and emotional stress. Coupled with its ability to boost the immune system, astragalus can help prevent and treat upper respiratory tract infections including cold and flu symptoms.

Studies have also confirmed the anti-inflammatory, antibacterial and antiviral properties of this herb.

There is good evidence to suggest that astragalus inhibits the growth of cold viruses. In addition, it enhances the functions of certain immune cells including macrophages and promotes the release of the antiviral protein known as interferon.

Astragalus is sold in tablet and capsule forms. It is also available as tinctures and, in Asian countries, even as injections.

In low and moderate doses, astragalus has very few side effects. It should, however, not be combined with lithium and drugs that suppress the immune system.

4. Ginger

Ginger is the herb prepared from the rhizomes of Zingiber officinale. It is also an ancient remedy, especially in Asian traditional medicines.

For more than 2,000 years, ginger has been used to treat gastrointestinal problems, arthritis and heart conditions. Currently, it is still used to treat these conditions as well as nausea caused by motion sickness, pregnancy, and chemotherapy. Other indications for garlic include the treatment of painful menstrual periods, cold and flu symptoms.

Researchers have found the sesquiterpenes in ginger to be responsible for the herb’s antiviral activities.

Specifically, these compounds are active against rhinoviruses which are responsible for 80% of common cold cases.

Other ingredients of the herb can also help relieve cold and flu symptoms. For example, the gingerols and shogaols present can suppress cough and reduce pain, aches, and fever.

5. Garlic

Garlic and onion, the related bulb, can also be used to treat cold and flu. Both plants are used as foods and herbal remedies in traditional medicine.

The antioxidant property of garlic makes it useful for reducing oxidative stress. The herb is also used to treat related cardiovascular conditions including high blood pressure, high cholesterol levels, and atherosclerosis.

Furthermore, garlic has antiviral and immune-boosting properties that are both useful in the treatment of cold and flu.

In one study, people who took garlic for 12 weeks during the cold season experienced fewer episodes of common cold than those who were given a placebo. In addition, the researchers found out that those who came down with cold in the garlic group got better faster than those in the placebo group.

Because garlic reduces the production of mucus, it can help relieve symptoms of cold and flu such as a runny nose and productive coughs.

Lastly, vitamins A, C, and E found in garlic can make some contributions to its effectiveness against cold and flu.

6. Siberian Ginseng

Although named a ginseng, the Siberian ginseng (Eleutherococcus senticosus) is not true ginseng like the Asian ginseng (Panax ginseng) and American ginseng (Panax quinquefolius).

In fact, Siberian ginseng contains a different set of active phytochemicals than true ginsengs and it has a different therapeutic profile too.

A set of unique compounds found in this herb known as eleutherosides can stimulate the immune system.

A study found that people who took Siberian ginseng over a period of 4 weeks had higher levels of T cells than those who did not.

This study demonstrates that Siberian ginseng can raise the level of certain immune cells that are useful to the immune system defense against common cold and influenza viruses.

A few studies also found that the combination of Siberian ginseng with andrographis (discussed later in the article) “cured” the flu faster than amantadine, a prescription flu medication.

People placed on blood thinners, corticosteroids, sedatives, immunosuppressants, diabetes drugs, digoxin, and lithium should not take Siberian ginseng without medical supervision.

7. Licorice

Licorice is known as sweet root because it contains a compound that is sweeter than sugar.

This root also has medicinal properties and it is used in the treatment of a variety of diseases including peptic ulcer, eczema, liver problems, and the common cold.

Licorice is an expectorant that is useful for relieving cough. It can help clear lung congestions.

In addition, it has a potent antiviral property. The antiviral activity of licorice root involves stimulating the release of interferons, the family of natural antiviral proteins.

Licorice is available as dried, powdered roots that are commonly sold as tablets, capsules and herbal tea.

Avoid licorice extracts that contain glycyrrhizin as this ingredient is associated with side effects such as a peptic ulcer. Rather than these, choose DGL (deglycyrrhizinated licorice) products.

8. Lemon Balm

Lemon balm is also a pleasantly tasting herb. This member of the mint plant family is known for its calming effect on the body. Therefore, it is used to treat stress and anxiety as well as promote sleep.

Lemon balm also has antiviral properties against herpes and HIV viruses but it is unclear whether it can also inhibit the growth of the influenza virus.

However, lemon balm can help treat the symptoms of cold and flu. Because it promotes rest and relieves stress, it can help shorten the duration of your cold and flu symptoms.

9. Goldenseal

Goldenseal is often combined with echinacea for preventing and/or treating the common cold.

Although there is no hard evidence to suggest that goldenseal can cure colds or the flu, its antibiotic activities can help people suffering from cold and flu. In addition, studies confirm that goldenseal strengthens the immune system by activating macrophages that are known to destroy viruses.

Goldenseal is generally safe and well-tolerated but it should not be taken by pregnant and breastfeeding women. In addition, this herb may cause skin irritation and increase photosensitivity.

Avoid goldenseal when taking digoxin, tetracycline antibiotics, and blood thinners.

10. Andrographis

Andrographis paniculata is a medicinal herb commonly used in Chinese and Indian traditional medicines.

Because of its popularity in Ayurveda medicine, it is sometimes referred to as Indian echinacea. Andrographis is commonly combined with Siberian ginseng (for example, in Kan Jang, a Scandinavian cold remedy).

Researchers believe that andrographis boosts the immune system by promoting the activities of NK (natural killer) cells. Because NK cells are part of the first line of defense mounted by the immune system, this ability of the herb can help prevent and/or treat cold and flu.

A 2004 study involving 896 volunteers found andrographis more effective than a placebo in the treatment of upper respiratory tract infections.

A 2003 study compared the efficacies of Kan Jang and amantadine. The study found that the study participants who took the andrographis/echinacea combination got better 3 days before those who took the prescription flu medication.

In addition, the researchers found that andrographis lowered the risk of severe flu and its complications.

A 2002 study published in the journal, Phytomedicine, also found Kan Jang effective in the treatment of acute upper respiratory tract infections.

Specifically, the researchers identified that this andrographis preparation relieved flu symptoms such as sore throat, nasal congestion, and headache.

Andrographis is effective for cold and flu because of its anti-inflammatory and immunostimulant properties.

Experts recommend taking 400 mg of andrographis 3 times daily. It is sold in capsule and tincture forms.

This herb is safe although it can cause side effects such as nausea, diarrhea, fatigue, headache, and allergic reactions.

Andrographis should not be used along with blood thinners and drugs used for hypertension.