Welcome to Healing Well! That type of diarrhea can occur after Nissen due to irritation to the vagus nerve. I had the problem intermittently (and like you, just in the morning) throughout the first year and even into the second, when it suddenly stopped.
Is it possible that you're challeging your wrap more just now--eating faster and not chewing your food completely? When something like this changes mid stream during the first year, that's my first suspicion. Try slowing down with your eating, and chewing your food until it's a creamy consistency. Stay away from raw veggies and things that will not be chewed fully.
Odds are that you've irritated your wrap or stomach, and it's reacting with dumping. Can you hear gurgling?
Actually, I'm four years post-op and very occasionally, when I get my stomach revved up with gastritis, I can get an episode of dumping. My guess is that if you take it easy with eating, chew your food carefully, and baby your stomach for a couple of weeks, you can get back to normal.
Glad you've joined the forum's Wrapped Club!
Nissen Fundoplication 2/09
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