Patients with psoriasis frequently use preparations of plant extracts. Physicians need to be aware of the current evidence concerning these products. This review evaluates the efficacy and safety of preparations of plant extracts used topically for psoriasis. Searches were conducted in PubMed, Embase, the Cochrane library, two Chinese databases and article reference lists. Randomized controlled trials investigating extracts of single plants were included. Preparations of multiple plants and combinations of plant extracts plus conventional therapies were excluded. Two authors conducted searches, extracted data and assessed risk of bias. Outcomes used in meta-analyses were: clinical efficacy, Psoriasis Area and Severity Index score, and quality of life and symptom scores. The 12 included studies investigated extracts of: Mahonia aquifolium (n = 5), Aloe vera (n = 3), indigo naturalis (n = 2), kukui nut oil (n = 1) and Camptotheca acuminata nut (n = 1). Methodological quality was variable. Six studies provided data suitable for meta-analysis of clinical efficacy, and five were vs. placebo (relative risk 3·37, 95% confidence interval 1·36-8·33). Experimental studies indicate components of indigo naturalis, Mahonia and Camptotheca have anti-inflammatory, antiproliferative and other actions of relevance to psoriasis. The clinical trial evidence provides limited support for preparations containing extracts of M. aquifolium, indigo naturalis and Aloe vera for the topical management of plaque psoriasis based on multiple studies. No serious adverse events were reported. Because of the small size of most studies and methodological weaknesses, strong conclusions cannot be made. The magnitudes of any effects cannot be measured with accuracy, so it is difficult to assess the clinical relevance of these preparations.

This systematic review and meta-analysis of randomized controlled trials (RCTs) examined the topical use of multi-herbal formulations for the management of psoriasis vulgaris. Studies were identified from PubMed, Cochrane library, EMBASE, and the Chinese databases CNKI and CQVIP. Methods were according to the Cochrane Handbook and meta-analyses used RevMan 5.1. Nine studies met the inclusion/exclusion criteria. The comparisons were with placebo and/or anti-psoriatic pharmacotherapy (APP) with two studies having three arms. The pooled meta-analysis data indicated the topical herbal formulae improved overall clinical efficacy (defined as 50% improvement or greater) when compared with: topical placebo (plus oral herbal co-intervention); topical APP alone; and topical APP (plus pharmaceutical co-intervention). Improvement was evident in Modified Psoriasis Area and Severity Index (PASI) score when topical herbal formula was compared to placebo (plus oral herbal co-intervention). No serious adverse events were reported. The most commonly used herbs were Sophora flavescens root and Lithospermum erythrorhizon root. Experimental studies reported that these herbs and/or their constituents have anti-inflammatory, anti-proliferative, anti-angiogenic, and tissue repair actions. These actions may at least partially explain the apparent benefits of the topical multi-herbal formulations in psoriasis.

This systematic review examines the current state of the evidence for the efficacy and safety of herbal medicines (HMs) used topically in conjunction with anti-psoriatic pharmacotherapy (APP) in the treatment of psoriasis. Searches were conducted in September 2012 of PubMed, EMBASE, Cochrane Library, two Chinese databases (China National Knowledge Infrastructure and Chinese Scientific Journals Full Text Database) and of article reference lists. We included randomized controlled trials published in English, Chinese or Japanese that investigated topical HM combined with APP used systemically and/or topically compared to pharmacotherapy alone. Studies employing phototherapy were excluded. Two authors conducted searches, extracted data on study characteristics and outcomes, and assessed Risk of Bias. Disagreements were resolved by discussion with a third author. Eight studies met the inclusion criteria. All used multi-herb formulae, four in herbal baths, three in herbal ointments or creams, and one as herbal steam. The pooled data indicated a benefit for the add-on effect of herbal therapy to APP. Adding these topical HMs to conventional pharmacotherapy appeared to produce short-term additional clinical benefits. No serious adverse events were reported. Experimental studies suggest that some of the herbs possess anti-inflammatory, anti-pruritic, and/or anti-proliferative activities. However, these results need to be interpreted with caution due to methodological weaknesses and the lack of replicated studies. Studies that address the identified methodological deficiencies are required to further investigate the efficacy and safety of these HMs as adjunct therapies for psoriasis.

Various forms of complementary and alternative medicine are used in psoriasis. Among these, herbal medicines are frequently used as systemic and/or topical interventions either as a replacement for or in conjunction with conventional methods. The benefit of such use is unclear. This review is to provide an up-to-date review and discussion of the clinical evidence for the main kinds of herbal therapies for psoriasis. Searches of the biomedical databases PubMed (including MEDLINE), EMBASE and CINAHL were conducted in December 2011 which identified 32 clinical studies, all published in English. Twenty of these primarily tested topical herbal medicines and were thus excluded. The 12 studies that evaluated systemic use of herbal medicines were included in the review. Four were case series studies and the other 8 were controlled trials. In terms of interventions, 4 studies tested the systemic use of plant oils combined with marine oils and 8 studies tested multi-ingredient herbal formulations. The clinical evidence for plant and animal derived fatty acids is inconclusive and any benefit appears to be small. For the multi-herb formulations, benefits of oral herbal medicines were shown in several studies, however, a number of these studies are not controlled trials, a diversity of interventions are tested and there are methodological issues in the controlled studies. In conclusion, there is promising evidence in a number of the studies of multi-herb formulations. However, well-designed, adequately powered studies with proper control interventions are needed to further determine the benefits of these formulations. In addition, syndrome differentiation should be incorporated into trial design to ensure effective translation of findings from these studies into Chinese medicine clinical practice.