What is Thuja?

Thuja is a type of coniferous trees in the Cupressaceae family. The leaves and leaf oil have been traditionally used as medicine. It contains chemicals affecting the immune system.

What are the benefits of Thuja?

Traditional uses for thuja include respiratory tract infections such as bronchitis, bacterial skin infections, and cold sores. It is also used for painful conditions including osteoarthritis and a nerve disorder that affects the nerves of the face called trigeminal neuralgia. It is believed to encourage the ridding of phlegm in coughs (expectorant), to boost the immune system (as an immunostimulant), and to increase urine flow (as a diuretic). Thuja is sometimes applied directly to the skin (topically) for joint pain, osteoarthritis and muscle pain. The oil is also used for skin diseases including warts and as an insect repellent.

Immune stimulant

Thuja is known to activate certain arms of the immune system [i] including CD4-Positive T Cells [ii]. It is also known to increase antibody production via antibody-producing lymphocytes. Other immune boosting actions were seen in mice after local contact with active components of the thuja extract in the gut or in the upper part of the bronchial system (respiratory tract), cells are able to react to an additional immune stimulation. GALT (gut associated lymphoid tissue), the immune layer in our intestines can also be enhanced by thuja extracts [iii].

Thuja has also be proposed as a supportive therapy to standard antibiotics. Many antibiotics are known to have a suppressive effect on the immune system. A total of 53 patients scheduled to receive antibiotics for treatment of bronchitis (as an example of a severe bacterial infection requiring antibiotics) were enrolled in a double-blind, placebo-controlled study. Patients were of 12 mg three times daily) or placebo. The group provided thuja showed a significantly faster improvement in response to the treatment [iv].

Antiviral properties

Thuja has antiviral actions and has been seen in case studies to successfully treat verrucae caused by the human papillomavirus-driven verruca vulgaris virus [v].

Thuja has been seen to inhibit damage caused by human immunodeficiency virus (HIV), including HIV dependent cell death [vi].

Its antiviral action is also thought to benefit acute colds, and viral respiratory infections. Administration of thuja caused rapid onset of improvement of cold symptoms in 238 patients included in the study. It was concluded by the author of the study that administration of thuja as soon as possible after initial cold symptoms appear would be most effective at attenuating a cold [vii].

In another double-blind, placebo-controlled study, patients suffering from acute common cold were randomised to receive a Thuja daily dose corresponding to 6 mg three times daily or placebo foreground a week. The patients themselves evaluated the effects of their treatment on specific symptoms and general feelings of wellness. This study showed the therapeutic benefit and superiority of thuja versus placebo for decreasing the duration of the common cold and alleviating symptoms. Again, it was said greater benefit can be expected if patients with the common cold are able to start taking the drug as early as possible after appearance of initial symptoms [viii].

Regarding influenza, in a study, thuja was administered to mice in a mixture of Baptisiae tinctoriae and Echinaceae, to investigate infection. It was assumed that the positive effect of this extract exerted on influenza infected mice is achieved firstly by its immune system stimulating (immunostimulant) activity and that the direct antiviral activity is rather of secondary role [ix](7).

Safety and Precautions

Pregnancy and breastfeeding

Thuja is not safe during pregnancy and breast-feeding, it may cause miscarriage and may transfer to the infant in breastmilk.

Autoimmunity

Conditions such as multiple sclerosis, systemic lupus erythematosus, rheumatoid arthritis are said to be autoimmune conditions. It is thought thuja may cause the immune system to become more active and thus there is some concerns surrounding over-stimulation of the immune system in autoimmune conditions.

Seizures

Taking thuja might cause seizures in some people. Thuja should be avoided those with a history of having seizures.

Interactions

(please consult with prescribing GP prior to use):

Seizure threshold lowering drugs

Anticonvulsants such as phenobarbital, primidone, valproic acid, gabapentin and others

Immunosuppressants

St John’s Wort [x]

Side effects

Recommended dose of thuja are likely safe, however large doses of thuja can cause nausea, vomiting, diarrhoea and seizures.