The use of botanical extracts as anti-inflammatory medicine is a common practice among patients suffering from eczema who are seeking "natural" remedies, particularly in response to the failure or intolerance of certain medicinal treatments. Calendula oil is often mentioned as a relief for eczema problems. But what about its effectiveness on this skin condition?
The medicinal effects of calendula oil against eczema?
Does calendula oil truly have an effect on eczema?
The calendula was first used before the 12th century for its anti-inflammatory and soothing properties. It is widely believed that its use can be beneficial in the treatment of eczema. Indeed, its application to affected areas would help to reduce inflammation. However, the exploration of calendula in the treatment of eczema is limited. Although a few studies have shown that calendula had an effect in the treatment of certain skin disorders, there is, however, no real evidence of the effectiveness or safety of using calendula on eczema.
A randomised double-blind clinical trial (n = 66) demonstrated that the use of a calendula ointment on children under 3 years old suffering from nappy rash, a common type of dermatitis in infants and children characterised by an acute inflammatory reaction in the area covered by the nappy, was more effective than a cream with aloe vera, as evidenced by fewer rash sites after 10 days of application 3 times a day. However, other research has shown that it was not as effective as the use of bentonite, a type of natural clay rich in minerals.
Indeed, a study has shown that when infants were treated with 50% bentonite (n=30), 88% of lesions began to heal within the first six hours, compared to only 54% of lesions in the group treated with 1.5% calendula (n=30). The results thus indicate that calendula could help to reduce redness, severity and the extent of the area affected by infantile diaper dermatitis, often caused by babies' wet nappies, thanks to its anti-inflammatory properties. Moreover, you can find it in some over-the-counter nappy rash creams.
Similarly, a randomised phase III clinical trial was conducted to assess the effectiveness of Calendula officinalis compared to trolamine (Biafine) in preventing erythematous radiodermatitis induced during breast cancer radiotherapy, the severity of which varies from mild erythema to severe erythema. 254 patients who had undergone surgery for breast carcinoma and were due to receive post-operative radiotherapy (conservative surgery or mastectomy) were randomly divided between the application of an ointment containing 20% calendula in vaseline (126 patients) and the application of trolamine (128 patients) on the irradiated areas after each session. The occurrence of acute dermatitis of grade 2 or higher was significantly lower (41% versus 63%) with the use of calendula than with that of trolamine. Furthermore, patients receiving calendula less frequently interrupted radiotherapy and the pain induced by radiation was significantly reduced.
These various studies suggest that the topical application of calendula could serve as a treatment for nappy rash and as a preventative measure against the onset of dermatitis induced by radiotherapy, effects attributed to its anti-inflammatory properties. It is therefore likely that calendula may also improve eczema, although further research into the therapeutic effects of calendula on this inflammatory skin disease is strongly recommended.
By what mechanisms?
The effects achieved with calendula could be attributed to its anti-inflammatory properties. While the mechanism of action is poorly understood, the flavonoids and saponins found in calendula could prevent the release of enzymes and histamine that cause sensitivity and inflammation, and could help soothe redness and pain. At the same time, it could reduce the migration of white blood cells to the inflamed area by decreasing the permeability of blood capillaries, due to the presence of triterpenoids.
MONTBARBON X. & al. Phase III randomized trial of Calendula officinalis compared with trolamine for the prevention of acute dermatitis during irradiation for breast cancer. Journal of Clinical Oncology (2004).
SAHEBKAR A. & al. A randomized comparative trial on the therapeutic efficacy of topical Aloe vera and Calendula officinalis on diaper dermatitis in children. Scientific World Journal (2012).
MASHAIEKHI M. & al. The effects of Bentonite and Calendula on the improvement of infantile diaper dermatitis. Journal of Research in Medical Sciences (2014).
MASHAIEKHI M. & al. Comparing the effects of Bentonite & Calendula on the improvement of infantile diaper dermatitis. A randomized controlled trial. Indian Journal of Medical Research (2015).