"Thyroid Problems"

I was put onto Thyroxin in 1999, then in 2011 this was changed to Levothyroxin. I have now developed an adverse reaction to this drug, so much so that I am unable to take it. Now I am discovering that there aren't a lot of alternatives. After a lot of research I learnt that Levothyroxin is synthetic which I am sure is why I am reacting to it. I now have a referral to an Endocrinologist but that isn't until June, and this is an urgent appointment. My Doctor is unable to prescribe Natural Desicated Thyroid as an alternative to the synthetic, I have tried to obtain a private prescription for NDT's either. I am feeling increasingly tired as I was only able to take half of my normal dose of 100mg of Levo for the past three months, then the side effects became so bad that I was sick whenever I took it, so haven't taken any now for two weeks. I find it astonishing that I am in this situation and that there isn't any alternative it seems.