This tropical legume contains L-DOPA, a precursor to the neurotransmitter L-dopamine. Mucuna Pruriens has also been shown in laboratory studies to increase erection frequency and sexual activity.
(Source: J. Ethnopharmacol. 2009 Apr 21;122(3):497-501. doi: 10.1016/j.jep.2009.01.032. Epub 2009 Jan 31.)