If a healthy 35 y/o male, with migraines, takes 2 excedrin several times a week (not every single week, sometimes migraine free for couple of weeks) for years, could that lead to liver problem? never take more than 2 in a day. not a drinker or smoker?

See a Neurologist for treatment, treating yourself is not in your best interest. Self treatment can lead to self destruction.

This pattern in the described male can lead to increased frequency and intensity of the migraines, resulting in the syndrome of Chronic Daily Migraines, which is likely already present. See a neurologist and get this pattern aborted. Doubt liver issues would occur but best to do blood studies.