Aspirin is no longer recommended for primary prevention of heart attacks due to emerging evidence of increased risk of gastrointestinal hemorrhage (still recommended for secondary prevention) 

Several medications have been recalled in recent years due to concerns of carcinogenic effects not previously known 

Swine flu vaccine halted 

Recent published data confirms the benefits of statin medications in preventing heart disease may have been over stated 


“In the annals of modern medicine, it was a horror story of international scope: thousands of babies dead in the womb and at least 10,000 others in 46 countries born with severe deformities.” 

Beta blockers were initially not recommended in heart failure but are now standard of care 

Clopidogrel was previously recommended for patients with STEMI (particular type of heart attack) but this indication was subsequently removed