Palmoplantar pustulosis and pustulotic arthro-osteitis treatment with potassium iodide and tetracycline, a novel remedy with an old drug: a review of 25 patients

Abstract

Background: The use of potassium iodide (KI) to treat palmoplantar pustulosis (PPP) and pustulotic arthro-osteitis (PAO) has not previously been reported. Here, we report the first successful treatment of PPP and PAO with KI.

Patient and methods: Among 25 patients with PPP, seven had an associated PAO. All patients were administered 900 mg KI three times per day for 3 months. Overall, 12 patients received this medical treatment for the first time or had >6 months interval since the last therapy for PPP. The other 13 patients who were nonresponsive to tetracycline for >3 months prior to KI treatment were treated with a combination of KI and tetracycline. All seven patients with PAO were included in the tetracycline and KI-treated group.

Results: More than 70% of patients demonstrated complete clearance or ≥50% improvement in palmoplantar pustular psoriasis area and severity index (PPPASI) from baseline. In the group with <50% improvement in PPPASI from baseline, all except one patient were smokers. In the KI with tetracycline treatment group, approximately 80% demonstrated improvement. At the end of 3 months, there was remission of arthralgia in five out of seven PPP patients with PAO.

Conclusions: Treatment with KI and/or its combination with tetracycline may be a useful treatment for PPP/PAO. Smoking may affect the effectiveness of these treatment modalities.