In a study released in 2012, a nutritional supplement made of propionyl-L-carnitine, L-arginine and niacin was tested for its potential effects on erectile dysfunction.  The results show that men with erectile dysfunction experienced a small yet significant improvement in erectile function after 3-month supplementation with this nutraceutical.  Up to 40% of patients improved erection while 77% of patients partially responded to the treatment.  The authors suggest that this nutritional supplement may be used as first-line or adjunctive treatment to PDE5 inhibitors to treat erectile dysfunction. (David Liu)Gianfrilli D1, Lauretta R, Di Dato C, Graziadio C, Pozza C, De Larichaudy J, Giannetta E, Isidori AM, Lenzi A.  Propionyl-L-carnitine, L-arginine and niacin in sexual medicine: a nutraceutical approach to erectile dysfunction. Andrologia. 2012 May;44 Suppl 1:600-4. doi: 10.1111/j.1439-0272.2011.01234.x. Epub 2011 Oct 4.