What I'm about to do is play devil's advocate.

Too many investors get excited and jump into a stock without comparing and contrasting against other possibilities.

So before buying shares in pharmaceutical giant Pfizer (NYSE: PFE), read on as I give you one reason to consider one of these five other stocks. The first three offer growth opportunities to complement Pfizer's blue-chip maturity. The last two are large-company alternatives.

Intuitive Surgical (Nasdaq: ISRG)
Intuitive Surgical builds da Vinci surgical systems. Robotic surgery: Talk about disrupting the status quo. And this isn't some pie-in-the-sky concept -- Intuitive Surgical makes real sales and real profits. It has grown profits by 50% a year over the past five years; analysts expect 25% growth for the next five years.

Dendreon (Nasdaq: DNDN)
Dendreon's prospects rest on its prostate cancer drug Provenge, which was approved by the Food and Drug Administration back in April. For the uninitiated, the economics don't work like those for your prescription heartburn medicine. A month of therapy costs more than a BMW -- $93,000!

We'll be able to see the initial sales figures on Tuesday when Dendreon reports earnings. However, our biopharma expert Brian Orelli warns that the initial sales figures aren't as important as the size of the eventual ramp-up.

Cell Therapeutics (Nasdaq: CTIC)
Whereas Dendreon's fate is a matter of sales, Cell Therapeutics' rests largely on whether its non-Hodgkin's lymphoma (NHL) drug, pixantrone, gets FDA approval. Cell Therapeutics' initial application to market the drug was turned down, so its fate now rests on the results of an additional late-stage clinical trial. As its stock price gyrations suggest, this is a binary type of stock -- i.e., you'll either win or lose big.

UnitedHealth Group (NYSE: UNH)
As fellow Fool Morgan Housel has argued, UnitedHealth is still trading around levels it was at when there was more uncertainty about health-care reform. And those levels are extraordinarily cheap -- a single-digit multiple on free cash flow -- if you believe the profitability of the health insurers will hold up reasonably well going forward. If you buy the argument for UnitedHealth, be sure to check out WellPoint (NYSE: WLP). Similar arguments can be made for it.

Teva Pharmaceutical Industries (Nasdaq: TEVA)
As we worry about Pfizer's ability to replenish its drug pipeline as its superstar drugs come off patent, generic-drug maker Teva is trading near 52-week lows. Just as the first three companies offer complementary growth prospects, Teva's generic drug portfolio could complement Pfizer's branded drug focus.

The final reminder
As you decide among Pfizer and these other alternatives (or none of the above), remember that one compelling reason does not an investment thesis make. I present these options to encourage you to compare and contrast as you do your research. Good luck!

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