FDA internal reports unhappy about rosiglitazone (Avandia)

Research Ties Diabetes Drug to Heart Woes

 

http://www.nytimes.com/2010/02/20/health/policy/20avandia.html

 

Does anyone know why Avandia increases the risk of CHD? Is because of efficiently lowing the glucose level (too low)? Or any other side-effects.