With the Ides of March approaching, we asked our team of Fool.com healthcare contributors to identify big pharma stocks that look like good picks this month. Read on to see why Dan, Todd, and Brian think Pfizer (NYSE:PFE), Bristol-Myers Squibb (NYSE:BMY), and Johnson & Johnson (NYSE:JNJ) are worth taking a look at now.

Dan Caplinger
I've been impressed with Pfizer's performance recently despite the concerns its most recent earnings report raised in late January. Even though Pfizer saw its overall revenue shrink somewhat, it still managed to eke out greater earnings per share, thanks largely to its massive share buybacks that took advantage of Pfizer's impressive free cash flow. Still, weak guidance led many shareholders to have big doubts about the stock.

More broadly, investors are torn about which strategy might be best for Pfizer's future. Some believe the drugmaker is destined to break itself apart, dividing its business into two parts in an effort to give investors a choice between a high-growth, high-risk innovative-products business and a higher-income, less-volatile established-products company. Others expect Pfizer to stay on the acquisition trail, perhaps by buying up promising biotech companies that could help it bolster its pipeline to replace sales lost to patent expirations.

At the end of the day, Pfizer has an impressive pipeline that can deal with the occasional disappointment in clinical trials without endangering the entire company. Whether the company decides to split or pursue M&As -- or perhaps use a combination of both -- Pfizer remains a compelling company with plenty of strategic options at its disposal.

Todd Campbell
That was lightning fast! The FDA's approval of a label expansion for Bristol-Myers Squibb's Opdivo is one of the fastest approvals I can remember.

Source: Bristol-Myers Squibb.

Opdivo's green light for use in post-chemotherapy non-small-cell lung cancer (NSCLC) patients significantly increases its addressable patient population, and that makes it my top pharma stock to buy this month.

The unmet need for new lung cancer treatments is massive. More people die of lung cancer in the U.S. every year than from any other cancer, and an estimated 224,210 new cases were diagnosed last year alone. The approval means that doctors will have a new weapon to treat squamous NSCLC, which accounts for 25% to 30% of all lung cancers. In trials, 41% of Opdivo patients were alive one year later -- more than two times historical levels for the disease.

In addition to its life-changing impact on patients, the approval also solidifies Opdivo's chances for achieving billion-dollar blockbuster status. Despite having to compete with other new drugs that work similarly, such as Merck & Co's Keytruda, analysts think Opdivo's sales could hit $3 billion by 2017. If so, Opdivo's positive impact on Bristol-Myer's profits makes it one stock that could be worth buying.

Brian Orelli
March is a great month to buy Johnson & Johnson (NYSE:JNJ). So is every other month. It's one of those companies that you can buy anytime, forget that it's in your portfolio, and sit back and collect dividends for years.

Or better yet, use the company's Dividend Reinvestment Program -- DRIP for short -- to use the dividend to buy additional shares without any fees or commissions. In fact, you can use the DRIP program to buy small amounts of Johnson & Johnson stock in every month of the year.

Granted, there are clearly better times to buy the healthcare conglomerate than others. Typically, it's a good time to buy when the dividend yield spikes; you get to collect a larger dividend relative to the price paid for the stock while waiting for the inevitable capital appreciation. But buying shares every month means you don't have to try to time the purchases and hope you hit the dip correctly.

Johnson & Johnson's dividend, around 2.7%, isn't the highest it's ever been, but it has been driven a little higher by the slight pullback in the stock price from the highs seen in January. And we're due for another increase in the dividend, likely next month. The company has raised its dividend for 52 consecutive years; it seems unlikely it would break that streak this year.