No its not caffeine addiction, one of the ingredients in tylonal is caffeine.
It's works faster cause soda is a liquid, and tylonal is a pill, it has to go through your whole body beforeit has an effect. Liquid travels faster.
I don't take medication or pills or anything so when i have a headache i drink a soda or coffee.
Caffeine addiction is not a far stretch I went through the same thing when I first found out I was pregnant. My doctor told me you can drink either one cup of coffee of you can have a 12oz soda a day and it won't harm the baby.