Apomorphine subcutaneous titration in Parkinson’s disease - the effectiveness and safety of apomorphine challenges: A Literature Review

This review examined the body of evidence to determine the efficacy of an apomorphine challenge. Its primary objective is to identify the dose of the most common adverse events involved with apomorphine challenges. The secondary objective is to determine whether a titration challenge is warranted prior to commencing Apomorphine therapy or an alternate option, such as slow titration, is more efficacious.

Results: The literature review was developed using the Cochrane handbook of systematic reviews. The search yielded 157 results, only 23 were included in the final analysis. Evidence is largely lacking and traditionally anecdotal and based on clinician experience. Studies inadequately control for reporter and rater bias, have small sample sizes; high level evidence is lacking.

Continuous rates range between 2-4mg/hr (Deleu, 2004) and an intermittent dose range between 4mg- 6 mg (Pahwa et al 2007); doses higher than this are likely to induce side effects. QT interval prolongation is linked with both apomorphine and domperidone use and an electrocardiogram (ECG) should be performed prior to commencing both medications.

A positive result for an apomorphine challenge is determined when there is a 20% improvement from baseline score in part III of the Movement Disorder Society – Unified Parkinson’s Disease Rating Scale (MDS- UPDRS), 30 minutes after a dose is given.

Lastly, review examines a theoretical way to titrate patients using the Tomlinson levodopa conversion.