I'm on Vyvanse which I love but I'm not on Effexor. It absolutely caused me sleeping trouble though and I take it really early in the morning, like before 6 AM if possible because I can't sleep if I take it later. The insomnia did not go away for me even after taking Vyvanse for a long time. It made me lose weight which was good but then stupid anti-psychotic I was put on made me gain weight. Kit.