Observational, prospective and multicentre study to evaluate the effectiveness of calcipotriene and betamethasone dipropionate aerosol foam (Cal / BD), prescribed according to clinical practice and following the Product Data Sheet instructions, in the topical treatment of nail psoriasis according to the change in the score of the Nail Psoriasis Severity Index (NAPSI) at 12 weeks of treatment with respect to the initial score.

Inclusion Criteria:

• Patients with nail psoriasis who start, according to clinical practice, topical treatment with calcipotriene and betamethasone dipropionate aerosol foam
• Patients who authorize their participation in the study by signing written informed consent.

Exclusion Criteria:

• Patients receiving treatment with systemic drugs or their prescription is scheduled for the next 3 months. However, may be included patients who receive the same systemic treatment regimen from at least 6 months before their inclusion in the study and up to 14 weeks later.
• Patients with any situation or state that in the opinion of the investigator discourages their participation in the study.

Patients diagnosed of nail psoriasis for whom are prescribed, according to clinical practice, a topical treatment. Will be included the first 60 patients that consecutively attend the participating centers and meet all the eligibility criteria.