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

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.

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.