Question normal

I saw this interesting man referred due to an episode of collapse. He described symptoms as if he is getting hypos. This wasnt documented hypo but he found symptoms getting better with MARS bar or sugary stuff. He was very well in himself and didnt have any other stigmata to suggest insulinoma.

He described the event in his own words as follows:

“I was going uphill, walking my dog and after about 5 to 10 minutes, felt that my vision was a bit blurry, as if I was looking through glazed glass. I felt shakiness in one arm, which then progressed to the other arm and I had to sit down on a bench, and took a mars bar because of the worry about hypoglycaemia. I never lost consciousness and never got confused and was aware of my surroundings throughout this episode. Another gentleman walked past me and asked me whether I was okay. He did not find me confused and didn’t witness any seizure activity. The symptoms settled almost immediately, within a few minutes of taking the mars bar”.

I was expecting post-prandial reactive hypoglycaemia as he used to be a drinker in the past but is currently not drinking and lives healthy life.

He had a prolonged OGTT which did confirm two hypos and he has raised insulin and C-peptide levels coupled with them.

Glucose 2.7 mmol/L
Insulin 19.0 mU/L
C peptide 1295 pmol/L

Thats a complete surprise. His medications include
• Perindopril 4 mgs od
• Amlodipine 5 mgs od
• Bisoprolol 2.5 mgs od
• Lansoprazole 30 mgs od
• Citalopram 20 mgs od

Could this be insulinoma? Could this be a drug effect? SU screen negative.