From the research section of the RLS Foundation. The lovely Doctor Ondo is working for us.
'The RLS Foundation has awarded a $37,000 grant to Dr William G. Ondo of Houston Methodist Neurological Institute to study a new medicine to treat RLS patients who have augmentation.
"Augmentation is a condition where RLS symptoms start to worsen after initially improving, while on dopamine agonist treatments such as pramipexole, ropinirole, Neupro, and levodopa. Since most patients with an urge to move initially respond to properly dosed dopaminergic medicines, augmentation is arguably the biggest practical impediment to successful chronic management of RLS" explains Ondo. "The exact mechanism of augmentation is not known, however, based on animal studies we performed, we hypothesize that it is caused by increased activity of dopamine type I (D1) receptors. In animal models these receptors in the spinal cord increased when mice models of RLS were chronically treated with typical dopamine drugs, specifically pramipexole. Dopamine type I receptors have many features which are the exact opposite of dopamine type 2 (D2) and 3 (D3) receptors in the spinal cord. The dopamine medicines still stimulate these D1 and the D2/D3 receptors, which we feel results in the contradictory effect that they both improve and worsen RLS at the same time."
"We have identified an investigational drug which blocks D1 receptors without blocking D2 and D3 receptors, ecopipam. In this small trial, we will administer this drug in a blinded manner to patients already on dopamine medications who have augmentation, to see if it can reverse the augmentation and improve their symptoms."
Pramipexole would appear to be the biggest monster.