Abbott Laboratories has acquired the drugs unit of Belgian drugs, chemicals and plastics maker Solvay for $6.5 billion, it announced today. In addition to the purchase price of $6.5 billion, Illinois-based Abbott will also pay up to another $440 million in contingent payments between 2011 and 2013, depending on the performance of certain products. The deal will add more than $3 billion to AbbottÔÇÖs annual sales, most of which will come from overseas.