I have been taking just T3 for a number of years but over the last few months the quality of the drug from the only British manufacturers has been very variable and one of the last lots I was prescribed, lot 81745, were particularly bad. I had to stop taking them as they were making me really sleepy, ill and mentally my dementia became really really bad. I have submitted a yellow card as I know other people have had problems too. My supply of T3 is carefully controlled by the Dr, and I now have 250 T3 from that batch that I can't take because of the fault with them. Has anybody suffered the same problem with a faulty batch of T3 and managed to get them replaced by the manufacturer? I am reluctant to go back to my Gp as he is not keen on me taking T3 and will use every excuse to try and get me off them, but they have transformed my life and given me back my life as it is now clear that my dementia is linked to the hypothyroidism.