Improvement of psoriatic onychodystrophy by a water-soluble nail lacquer

J Eur Acad Dermatol Venereol. 2009 Jul;23(7):832-4. doi: 10.1111/j.1468-3083.2009.03209.x. Epub 2009 Apr 8.


Background: There is a strong need for effective products, simple to use and safe for a chronic use in the management of nail psoriasis. Recently, a non-drug, water-soluble nail lacquer became available, containing hydroxypropyl chitosan (HPCH), horsetail extract (Equisetum arvense) and methylsulphonyl-methane (DMSO(2)). This product was effective in strengthening the nails and reducing fragility and roughness in brittle nails. A clinical trial was performed to verify whether this product was able to improve nail psoriatic signs and appearance.

Patients and methods: Thirty adult patients affected by mild to moderate symmetric psoriasis of the matrix and/or of the nail bed in at least one fingernail diagnosed more than 6 months before screening and with negative mycology findings were recruited. The nail lacquer was applied once daily on the affected fingernails of the left hand for 24 consecutive weeks. The right hand was used as control. The extent and severity of nail psoriasis was assessed on a target fingernail by means of the recently proposed Nail Psoriasis Severity Index (NAPSI) score. The value at baseline was 2.83 (+/- 0.99). At the end of treatment, the patients judged the treatment effect and their willing to continue product application. Adverse events were carefully recorded.

Results: Overall, 28 patients were included in the efficacy analysis. At the end of treatment, results showed a 72% reduction in pitting, 66% reduction in leukonychia, 63% reduction in onycholysis and a reduction of 65% in NAPSI score compared to baseline, respectively. No changes were observed in the untreated nails. Patients' treatment evaluation was classified as very satisfying or good by 78.6% of patients. The acceptability of the treatment was excellent in all patients both for the easiness and for the organoleptic characteristics of the product and 75% of them decided to continue the application after the end of the study. No adverse reactions were reported.

Conclusion: In our experience, the new water-soluble nail lacquer proved to be effective in decreasing signs and symptoms of nail dystrophy in psoriatic patients. The effect was particularly evident on NAPSI and on pitting. The product was very well accepted by the patients.

Publication types

  • Controlled Clinical Trial

MeSH terms

  • Administration, Topical
  • Adolescent
  • Adult
  • Aged
  • Female
  • Humans
  • Male
  • Middle Aged
  • Nail Diseases / therapy*
  • Psoriasis / therapy*
  • Solubility
  • Treatment Outcome
  • Water
  • Young Adult


  • Water