As real as her body is, her performance isn’t up to snuff.

Ed Zwick’s film is half a good movie; see it for the “and Other Drugs” part that kicks it off. That’s the portion infused with effervescence, pulling back the curtain on the cutthroat world of pharmaceutical reps that Jamie Randall (Jake Gyllenhaal) jumps into after he’s booted from his electronics sales job for banging his manager’s girlfriend on the clock.

Bubbling with charm (which he uses more or less to separate women from their panties), Jamie is assigned to pitch Zoloft to a Prozac-favoring physician populace. He does all right, but his career really rises when the penile-dysfunction pill known as Viagra is introduced to the market.

That’s interesting stuff (taken from Jamie Reidy’s “Hard Sell” memoir, the disc’s special features reveal), but not the friends-with-benefits relationship he carries on with Maggie (Hathaway), an artist with stage 1 Parkinson’s he meets during one of his doctor’s office visits. Being a womanizer, Jamie isn’t into commitment; being sick, Maggie isn’t, either. You know how that’s going to end. (Spoiler alert: Consider the first word of the title.)

What you don’t expect is that at the midpoint, Zwick puts the brakes on the corporate comedy and makes a hard right toward melodrama, not only to explore the story’s disease-of-the-week trappings, but to give Hathaway a chance to bait award votes. She tries too hard; her work is exaggerated and showy, whereas Gyllenhaal’s runs smooth and natural. He exudes the confidence of an Tom Cruise; she overacts, at one point even eliciting a burst of out-loud laughter from this reviewer, during her obligatory meltdown scene.

Just as the pills Jamie pushes don’t mix with alcohol, the goofy comedy doesn’t jive with Zwick’s attempts at seriousness. While Blu-ray viewers may experience an initial high, side effects may include nausea and drowsiness as that euphoria wears off. —Rod Lott