Hi. The glitazones are know to cause some increase in weight due to a level of water retention. Metformin usually helps reduce weight by reducing appetite. I'm not a doctor and it's not for me to tell you what drugs to take, but you might want to discuss with your GP the option of taking Sitagliptin (Januvia) instead of Pioglitazone. My GP offered me either one to add to my Metformin and Gliclazide and I chose Sitagliptin as it has no effect on weight and overall I judged it to have some, but fewer, side effects. I can't comment on your tiredness etc and there may be a good reason why your GP chose the glitazone for you. As far as I know both Pioglitazone and Sitagliptin don't add to the risk of hypos, so I think a discussion with your GP is needed.