hi my name is philomena..iv been taken eltroxin 100 micrograms for many years now....iv never had any problems with it but of late i started taken a mulitvitiam and got real bad headaches..i also get very bad cold sores on my bottom lip and when that ends it then appers inside of my nose...but i cant take anything for this as it causes the pain in my head to come back in my head again...why is there this reaction i dont take any other tablets just this eltroxin and just 1a day ....thank you.