The Associated Press reported yesterday that pharmaceutical giant Merck is buying Schering-Plough Corp. The merger will form the world’s second-largest prescription-drug maker, worth $47 billion in combined revenue in 2008. This comes six weeks after the largest drugmaker, Pfizer Inc., announced itself that it’s in the midst of acquiring Wyeth.

On NPR Morning edition today, Sean Nicholson from Cornell University said the move is an attempt to help big pharma regain firepower as they face multiple challenges, such as the imminent end of patent protection for the blockbuster drugs of the 1990s, a dearth of major new drugs coming out and the decrease of prescriptions in the US for the second consecutive quarter, a first "in recent memory,” Nicholson said.

That expensive drug sales drop in times of economic crisis make sense. What is unclear, however, is how much the online pharma business contributes to this trend. Arguably, buying drugs is not like buying a dress or an ipod. It is an not an expendable expense for cash-strapped customers... to a point. So, do people really by less drugs, or do they use more underground ways to get them?

If the latter is true, big mergers won't necessarily make big pharma better off.