I'm replying tonight, a bit late maybe. My input may be too late to be of any help to you.
I've used both Nardil and Parnate. Nardil worked quite well for me, Parnate not as much. Not many side effects except insomnia. Should work within a couple weeks--I can't remember. At the time (Nardil), I did not find the dietary restrictions very difficult to follow. But I was working then (I'm retired now) and my life was more disciplined. I liked generally Nardil. I can't remember why I stopped Nardil--that was back in 1993. I took Nardil again (early 2000s) in combination with Klonopin, and that combination worked great. I stopped those as well--reasons not important. I did not like Parnate as well as Nardil--just did not feel well on Parnate. Also, I had a hypertensive reaction on Parnate after eating a meal I'd had many times before--I think the restaurant used a type of wine on my meal that day that I reacted to. I survived that reaction w/o medical treatment, but if you have such a reaction get help immediately and explain to the responders why you're having the reaction.
I've recently (2015 into 2016, and early this year)had a couple extreme anxiety periods. In both cases, I believe the events were related to urinary tract infections. In the first event, I didn't get the required medical treatment for the infection until months after it was required and I barely survived. In that most recent event, we dealt with the infection immediately with antibiotics and I am doing OK now. Weird, but I'm now convinced there is a link (for me). Too bad I couldn't convince the psychologist of that back in 2016.