While some side effects should be expected when you have your 6 week BCG induction, unusual or / and disturbing ones should be reported to your medical team. When I had my initial induction ( 6 full dose treatments over seven weeks, last Autumn I had a few but manageable one's such as fatigue and muscular aches. Next week I shall start my first maintenance BCG treatment. Three treatments at 1/3 dosage for three weeks. While some side effects are to be expected, I do not expect anything severe. Since you are having severe one's again, this should be reported to your medical team. Maybe just a matter of increasing Tylenol.