Ways to deal with daytime sleepiness without meds and coffee?

Hi! I'm a female, 26, diagnosed with ADHD 3 years ago. All my life I've been struggling with excessive daytime sleepiness, and figured it's mostly related to ADHD (did a bunch of tests, talked to doctors, no physical health issues related to that). I was taking Ritalin for about a year, and it helped, but I'm currently unable to take the meds (they are unavailable where I currently live). I usually dealt with it by having naps during the day, and it helped, but it made me sleep worse at night, so I'm trying to eliminate the naps. What ways to deal with daytime sleepiness do you know? I've already tried red bull, and it also helped, but gave me terrible stomach ache (coffee is a no-go for similar reasons). Please help, I don't know what to do and feel super frustrated 😖