I'm on the 37mg capsule - If I miss a dosage even one day, that day my symptoms are: severe nausea, emotional mess, foggy brained and completely dysfunctional. I've been taking it for 4 years now (along with Adderall 40mg & Yasmin) and I don't know if it's just this medication or the whole combination, but I've gained 30 pounds!!! I've liked being on Effexor XR because before it I was on Zoloft and there was a huge mood swing coming down from Zoloft at the end of the day. This did not happen with Effexor. Except for the weight gain, I've been pretty happy with it otherwise.