Had to be narcotics.
 

I was flying home from an event on Monday, and I saw something unusual.

When I boarded the plane, there was a guy sitting on the aisle seat with a face that was literally beet-red. His expression was absolutely normal, and I had noticed him at the gate a few minutes earlier, and he looked fine, but, boy-howdy, there on the airplane he looked like an alien from another planet, or a Nebraska fan on his way home from the rivalry game.

I'm assuming he took some sort of drug because airplane travel made him nervous?

Does anyone know if there's an anti-anxiety drug that makes your skin bright red like cooked beets?

Niacin will do it. its called Niacin flush.

Alcohol.

Viagra!

https://www.publichealth.com.ng/how-to-get-rid-of-red-face-from-viagra/

Overweight?
or
Roseacea

+1 on the demon alcohol

He got caught looking at the cleavage of the women in the seat next to him, he got an erection that she noticed, and he was super embarrassed!

...when she had a bigger johnson.

BINGO! Has to be the cause!

Possible!

"Adequate treatments should be provided to mitigate the suffering of these patients. One of the most effective ways to accomplish this is through the use of the amide of niacin (nicotinic acid) known as niacinamide (nicotinamide). This B-vitamin has remarkable therapeutic benefits for those suffering from anxiety."

Was the guy Asian? Some Asians turn beet red when they drink. I remember my high school graduation and my friend had his cousins visiting from Boston. They weren't your typical re, they were splotchy red, like spots!

Caucasian, youngish (30-ish?), just a guy, tall, 20 or maybe 30# overweight, didn't look nervous or anything at the gate, and the red was solid, not splotchy.

Asian guy I knew in school got the red face when he drank.

Yes on Asian and alcohol. VERY good buddy of my turns bright red. He is of Japanese descent.

Niacin was my first thought however.

Sunburn?

https://actasdermo.org/en-facial-erythema-keys-differential-diagnosis-articulo-S157821901500102X

Somewhere around middle school IIRC my mother miscounted our vitamins one morning.

Both my brother and I had to leave school from a Niacin OD.

Your entire body goes flush and feels like intense pins and needles from head to toe.

Was not a pleasant experience.

My grandfather, dad's dad, was nicknamed Red. He would go to a bar and get a snoot full and turn very red in the face.

I was in a business meeting with the Prime Contractor for Billion dollar power project. The contract's top manager became angry for some reason (Dealing with GE, probably) and turned bright red. I had never seen anything like that, except in cartoons.

I knew one girl that would flush after a big-O. Everywhere!

My father took the nickname 'Rosy' while in WWII. His face always had a reddish hue, but it could turn bright red at any time...esp with exertion.

40 years later, he was diagnosed with Rosacea...a skin condition.

https://www.mayoclinic.org/diseases-conditions/rosacea/symptoms-causes/syc-20353815

This is funny but actually true. I've seen it several times. (Asians turning Red when drinking)