Investors looking for growth in the health-care sector often neglect the major pharmas in favor of their smaller counterparts. The idea is simple enough. Big pharmas are generally believed to be finished with rapid growth, and their biggest attraction as an asset is in their stability.

Yet, nothing could be further from the truth. As I discuss below, many big pharmas have more than doubled in share price over the past five years, while still providing less volatility than developmental stage pharmas. They also tend to offer stable dividends, further amplifying gains for patient investors.

With that in mind, here is my take on the prospects for two of the biggest names in health care going forward.

Will Bristol-Myers play the buyout game in 2014?
Bristol-Myers Squibb (NYSE:BMY) is a household name. As such, you might be surprised by the fact that its stock has absolutely blasted off over the past five years, rising more than 130%. During this period, Bristol-Myers has also offered investors a 2.7% dividend and hasn't been subject to the wild swings in share price seen in many smaller pharmas. In short, Bristol-Myers has been a sound investment the past five years.

Although the company has seen three blockbusters come off patent protection lately, earnings per share still nearly doubled in 2013 compared to 2012. The company attributes this jump in earnings to an increase in demand for Amylin-based products. As a refresher, Bristol-Myers bought Amylin in 2012 for its diabetes drugs, as part of the collaboration with AstraZeneca (NYSE:AZN).

What does 2014 hold for Bristol-Myers? Bristol-Myers decided to sell its share of its diabetes collaboration with AstraZeneca last December, receiving a handsome $4.1 billion as a result. Given that Bristol-Myers' late-stage candidates look somewhat sparse after this deal, I expect them to engage in the merger and acquisition game this year. The company hasn't been shy about going this route in the past, and the recent infusion of cash from the AstraZeneca deal gives it more than enough ammunition to make a deal. As such, you should definitely keep tabs on this health care goliath this year.

What will propel Merck this year?
Merck (NYSE:MRK) has also performed well over the past five years, with a handsome 72% increase in share price. But this increase in share price is far from the full story. Merck has also paid out a dividend around 3.5% over the last five years. So if you used a dividend reinvestment plan, or DRIP, your compounded gains would have been well over 100%. That's impressive by any standard.

Yet, it hasn't been all rainbows and unicorns for Merck investors. The company has lost patent protection for five former blockbusters over the past two years, and revenues are dropping as a result. In fact, this increase in share price has little to do with the performance of Merck's commercial portfolio. Instead, it's the result of the company's restructuring that began in 2008, as well as a share buyback program initiated May 1, 2013. In other words, the company is creating value for shareholders by laying off a substantial portion of its workforce, reducing its global footprint, and lowering the share count.

So, what's in store for Merck in 2014? Merck has a highly diversified pipeline of mid and late-stage clinical candidates, which should produce a handful of approvals in the U.S. next year. That said, I personally don't see anything in the current pipeline that's destined for blockbuster status. Some of the best candidates, such as Merck's hepatitis C drugs, will face stiff competition in the marketplace, if approved. With a small country's worth of cash on hand, I thus expect Merck to also go the acquisition route this year.

A Fool's take
Looking at the broader big pharma landscape, it's easy to understand why many investors have avoided these stocks. Companies like Eli Lilly (NYSE:LLY) and Merck have clearly struggled to deal with lost income from blockbusters coming off of patent protection, and this theme has played out numerous times across the sector. Yet, even Eli Lilly, with its nearly 4% dividend, would have produced compounded gains topping 60% over a five-year period. And Pfizer (NYSE:PFE) was thought to be dead money during this period because of the loss of blockbusters, but compounded gains for even this behemoth would have produced an eye-popping 120% return on investment. In sum, you shouldn't sleep on these health-care giants or you could end up missing out on some of the best opportunities for growth in the sector. Indeed, my bet is that this growth trend will continue for the foreseeable, fueled by an uptick in acquisitions in the sector.