According to a new Mayo Clinic study compulsive gambling with extensive losses (in two cases more than $100,000) by individuals without a prior history of gambling problems has been linked to a class of drugs commonly used to treat the neurological disorder restless legs syndrome (RLS).The study (which appeared in the Jan. 23 issue of Neurology) describes this compulsive gambling in RLS patients who are being treated with medications that stimulate dopamine receptors in the brain.

The extent of this problem is unknown. Apparently, it occurs only in a small number of RLS patients treated with drugs called dopamine agonists. Considering this potential side effect of dopamine agonists, the Mayo Clinic authors suggest that physicians screen all RLS patients for compulsive behaviors while taking a thorough medical history prior to prescribing dopamine agonists.

Patients should be monitored closely for signs of compulsive behaviors once dopamine agonist treatment has begun. The report suggests that the compulsion to gamble worsened with increasing doses of the dopamine agonists.