One of our strategies for treating Parkinson’s disease is to trick the brain by giving patients a dopamine agonist, and dopamine agonists pretend to be dopamine. They’re mimics, they’re a bit like a skeleton key. So if you have a dopamine receptor, the dopamine agonist can pretty much activate it so that it pretends to be dopamine.

Now these drugs are very effective, and interestingly they can be given once a day in a slow-release form – and that’s generally a bit more convenient for our patients. The dopamine agonists may have more in the way of side-effects than some of the other medications we have. The commonest being that patients may feel sleepy. The rarer side effects of dopamine agonists tend to get more headlines, and that’s impulse control disorder where patients might start gambling or spending money or excessive time doing things that they wouldn’t ordinarily do. And that can limit our use of the dopamine agonists.