As a patient, one always must be suspect of all medications that enter the body when experiencing new or unusual symptoms. I learned this hard way a few back as the patient. I have hypothyroidism that followed radiation treatment and have to take daily thyroid medication. There are trade name and generic substitute meds for many medications today. I was on a trade name drug but unknown to me at the time my pharmacist had substituted a generic when I dropped the med off for a refill. Within 2 days I began to feel profoundly fatigued. I was as tired in the mornnig after being in bed all night as I was before I went to bed with no clue it was my medication. I made an appointment with my ENT physician and my personal Internal Medicine physician over the ensuing month as I was barely functional. I was really beginning to believe my cancer had returned. Blood work and physical exams were normal. Both physicians including myself remained clueless. At 6 weeks and still completely exhausted, I began to think back to what may have changed in my life at the time the symptoms first showed up. Finally the lightbulb came on as I recalled refilling my thyroid medication. I went in my pharmacist where he discovered the med given was a generic substitute and not the trade name I had been on. I switched to trade name and within 48 hours the severe fatigue lifted.
This in no way should discouraged anyone from taking generic medications as there are considerable savings in doing this. However, if one begins to experience unusual symptoms from a type of medication they were taking previously without incident, one must be suspicious and talk with the doctor and pharmacist.