Echinacea supplements are prepared from several species of Coneflower (Echinacea spp). The most common Echinacea supplements are extracts from the roots of the Purple Coneflower (Echinacea purpurea). Echinacea is native to the Eastern North America, and this plant was an important part of the traditional medicines of many Native American groups who lived in the region. Echinacea extracts are purported to have many health benefits and are widely used in Naturopathic Medicine to boost the immune system and to treat respiratory infections, such as the common cold. Echinacea extracts are occasionally used in the Naturopathic treatment of acne.
Despite numerous claims that Echinacea helps support the immune system, there is little scientific evidence that commercially-available Echinacea extracts have any health benefits. One reason for this might be because the composition of Echinacea extracts varies significantly between providers. It is also unclear whether the active ingredients that are present in Echinacea formulations prepared from fresh Echinacea roots are also present in the commercial extracts. Overall, there is no compelling evidence to suggest that commercial Echinacea extracts are helpful for the treatment of infections, including acne.
Echinacea extracts have been claimed to have robust antibacterial properties which may help reduce the growth of acne-causing bacteria, such as Propionibacterium acnes. However, laboratory testing indicates that commercial Echinacea extracts tend to be weakly toxic to gram-positive bacteria, a group which includes P. acnes. Overall, it seems unlikely that commercial Echinacea extracts will be helpful acne treatments. While topical or oral treatments that use fresh Echinacea extract may be helpful for the treatment of acne, more research is needed on that subject.
Echinacea @ Wikipedia
The potential use of Echinacea in acne: control of Propionibacterium acnes growth and inflammation. Sharma, et al. 2011.
Applications of the phytomedicine Echinacea purpurea (Purple Coneflower) in infectious diseases. Hudson. 2011.
A review of phytotherapy of acne vulgaris: perspective of new pharmacological treatments. Azimi, et al. 2012.
Immunotropic activity of Echinacea. Part II. Experimental and clinical data. Balan, et al. 2012.
Medicinal plants for the treatment of acne vulgaris: a review of recent evidences. Nasri, et al. 2015.
Echinacea: an effective alternative to antibiotics. Tierra. 2008.
An Evaluation of Echinacea angustifolia in Experimental Rhinovirus Infections. Turner, et al. 2005.
Evaluation of Selected Medicinal Plants Extracted in Different Ethanol Concentrations for Antibacterial Activity against Human Pathogens. Wendakoon, et al. 2012.