yes and yes..I got one hell of a headache before the black tongue episodes..it hurt...get up out of bed hurt the first day then like a dull headache for about 3 days..then gone..my son one day of a real bad headache then one dull day..then gone...he never has had any tongue symptons liek turning black, either..at that time we were both just doing 1 pack aday..so, I didn't reduce our dosage..