Memory issues! Before I was diagnosed at 24, I seriously thought I was suffering from early-onset dementia. I constantly struggled with tip-of-the-tongue phenomenon, I would forget what I was talking about in the middle of a sentence, I started stuttering, and my teenage memories were a blur. Finding out that "transient global amnesia" is a known symptom of narcolepsy was weirdly such a relief, because then I knew I didn't have a malignant or progressive disease. Getting on medication definitely helped a little too!
The other surprising symptom is more of a comorbidity— ADHD.

Brain fog and memory issues

ok buy caffeine gum. It's what I use. I'm not on medicine. Each piece is a cup of coffee. Take two. Drink lots of water. The most I had to take at one time is 5. Don't wait until your loopy and don't commit when your a little sluggish. On a daily basis I consume 4 cups of coffee and 5-10 pieces of gum, but it's different to different people and make sure your not sensitive to caffeine.

There are other tricks. Make a song list of songs you can sing. It doesn't matter if you sound like a frog but sing like your at a concert. The more air you move into your body the harder it is to fall asleep.

If you want immediate relief inhale and exhale as deep and as shallow as you can three times and hold your breath on the third time until you can't anymore. Wait a couple minutes and do it again. You can even try this one now. You should find it gives you a tingle of energy. Don't go nuts on it or you will hyper ventilate.

Weight gain and recently I have begun to not sleep at night as opposed to not being able to stay up past 9 at the latest.