Thank you for this…I only took Fetzima for 3 days last week my racing heart was freaking me out. I too got two boxes of samples from my doctor after asking about something other than Cymbalta. I’ve been experiencing the brain zaps for a couple of days since I stopped the 40mg dose and switched to 20mg for a couple of days. They are driving me a bit nuts but thankfully I found your post and I feel better knowing that they’ll pass. I hope that you’re doing well.