Hi Fergie1065.
I was told I needed one for years and would never do as I was so worried about it in the end I gave in and had it done.
But for me they did it a different way the when through the nose (transnasal endoscopy) no sedation needed and just a little spray and that was it when via the nose cuts down on the gag reflex and it was cool went really well.
I think most of the people on nmp who have had a endoscope done have said it was not as bad as they have read on the internet and I agree.
Get it done and over with.
You will be ok