Plant extract that functions as an anti-inflammatory agent. It is a very good source of flavonoids and saponins, constituents that occur in many plants and convey antioxidant benefit.
There is one case report of this plant causing contact dermatitis, but this involved someone handling the whole plant, not the extract as it is used in cosmetics (Source: www.naturaldatabase.com).
Honeysuckle extract is most often used as a preservative.
Honeysuckle and Japanese Honeysuckle are used as preservatives due to their antiviral and antibacterial phytochemicals. Honeysuckle extract can be found independent of Japanese Honeysuckle extract, and is recommended to be used in concentrations of 5-10% of the formula. Honeysuckle and Japanese Honeysuckle are often sold as a blend, ratio uncertain, for use as a preservative, and is suggested to be used in concentrations of 0.5-2% of the formula. Given the difference in recommended use, it is likely Japanese Honeysuckle (Lonicera japonica) has the higher antimicrobial content.
Japanese Honeysuckle and Honeysuckle extracts have demonstrated the ability to deter microbial growth in acidic, low water environments for gram-positive and gram-negative Bacteria, though they are not as effective against mold (Papageorgiou et al. 2009). Another study done in 2009 yielded similar results, showcasing the strong antimicrobial activity of Japanese Honeysuckle (Rahman and Kang 2009).
The primary concern surrounding Honeysuckle extract and Japanese honeysuckle extract is that the extracts contain or are ‘parabens.’ This is a misnomer. Neither extract is known to contain parabens. It is important to make the clear distinction between parahyrdoxybenzoic acid and parabens, as parabens are a synthetic chemical designed to mimic parahydroxybenzoic acid (esters). Parahydroxybenzoic acid is a phytochemical present in a variety of fruits and vegetables including blueberries, cucumbers, and olives. It is assumed that parahydroxybenzoic acid accumulates in cancerous tissues similar to parabens, however, there is no literature that supports or disproves this. The exact composition of Honeysuckle extract and Japanese Honeysuckle extract depends on the manufacture, therefore contamination with other preservatives or chemicals is a possibility. A 2012 study found Japanese Honeysuckle extract to be contaminated for formaldehyde, which resulted in the aggravation of existing allergic contact dermatitis caused by formaldehyde releasers and fragrances (Gallo et al. 2012). It is believed the Japanese Honeysuckle extract leached the formaldehyde releasers from epoxy or phenolic-based plastic packaging (Gallo et al. 2012).