Ultrasound treatment of cutaneous side-effects of infused apomorphine: a randomized controlled pilot study

Apomorphine hydrochloride is a dopamine agonist used in the treatment of advanced Parkinson's disease. Its administration by subcutaneous infusions is associated with the development of nodules that may interfere with absorption of the drug. This pilot study assessed the effectiveness of ultrasound (US) in the treatment of these nodules. Twelve participants were randomly assigned to receive a course of real or sham US on an area judged unsuitable for infusion. Following treatment, no significant change was observed in measures of tissue hardness and tenderness. However, 5 of 6 participants receiving real US rated the treated area suitable for infusion compared with the 1 of 6 receiving sham US. Sonographic appearance improved in both groups, but more substantially in the real US group. Power calculations suggest a total sample size of 30 would be required to establish statistical significance. A full-scale study of the effectiveness of therapeutic US in the treatment of apomorphine nodules is warranted.