Anne Hathaway and Jake Gyllenhaal make a lot of whoopee in the film Love and Other Drugs. (20th Century Fox)

Like a bad combination of meds, Love and Other Drugs leaves you with a queasy, disoriented feeling. One minute you're watching a crass sex comedy about Viagra, the next it's a cloying tearjerker about Parkinson's disease.

One minute you're watching a crass sex comedy about Viagra, the next it's a cloying tearjerker about Parkinson's disease.

It's as if director Edward Zwick was trying to concoct the perfect medical-themed date movie that would appeal both to frat boys and to their Nicholas Sparks -reading girlfriends — but it all went horribly wrong. Only the staunchest fans of Jake Gyllenhaal and Anne Hathaway will be able to watch this without groaning at the humour and snickering through the tragedy.

Gyllenhaal stars as Jamie Randall, the wayward playboy son of a medical family who finds an outlet for his fast-talking charm as a representative of the pharmaceutical giant Pfizer. Posted to Ohio and placed under the tutelage of veteran sales rep Bruce (a crusty Oliver Platt), Jamie is charged with pitching the anti-depressant Zoloft to physicians.

One day, while trying to sweet-talk a Prozac-prescribing doc (Hank Azaria) into switching brands, Jamie meets Maggie Murdock (Anne Hathaway), a tart-tongued artist suffering from early-onset Parkinson's. (Their "meet cute" scene, in which Jamie gets a glimpse of Maggie's breast, is in the movie's equally schizoid trailer.)

We know Maggie's type: the ailing young woman who hides her fears behind a glib, tough-cookie pose. We know her because we've already seen her in movies like Love Story and Sweet November, to name only a couple. We also know Maggie doesn't want to get into a serious relationship with Jamie because she believes it will ultimately hurt both of them.

That doesn't stop them from having satisfying bouts of sex that run from wild, can't-get-the-pants-off-quick-enough humping against a kitchen counter, to slow, moaning ecstasy between the sheets. But despite Maggie's best efforts to keep things at the physical level, Jamie falls for her. She is, we are told, the first woman he has ever loved.

Then Pfizer releases Viagra and Jamie's career takes off. No longer stuck trying to hawk Zoloft, he now has the drug du jour in his sample cases and the medical community is clamouring to get their hands on his little blue pills.

The movie's screenplay, by Zwick, Charles Randolph and Marshall Herskovitz, is based on Jamie Reidy's memoir Hard Sell: The Evolution of a Viagra Salesman. An exposé of unscrupulous practices in the U.S. pharmaceutical industry, its revelations are evidently the source of the movie's attempted satire. But Reidy's book was published five years ago and a lot of the outrages here are old news. Will anyone be shocked that some sleazy doctors acquire Viagra for their personal orgies, or that Maggie leads bus tours of seniors to Canada to buy cheaper meds?

The Viagra jokes are also limp — as a pun-happy Maggie would put it. There's a comic sequence about the drug's most notorious side effect — priapism, or an unremitting erection — that even the Farrelly brothers would find tedious. But what's so disconcerting about this movie is that it segues straight from penis jokes into teary scenes between loving but frustrated Jamie and brave little Maggie. Hathaway, who already proved she could play the beautiful, difficult addict in Rachel Getting Married, now sets her sights on the beautiful, difficult invalid. With her pre-Raphaelite curls, big liquid eyes and toothy smile, the fragile-looking actress suffers gorgeously. You'll think not only of Ali MacGraw (Love Story) and Sandy Dennis (Sweet November), but of a younger Julia Roberts, too. You'll also have a hard time not laughing.

Maggie's a struggling artist who works in a café and lives in a big funky loft that only struggling artists in movies can afford. Successful salesman Jamie, conversely, is stuck sharing a small apartment with his ultra-annoying kid brother, Josh (Josh Gad), who has split from his wife. Josh has made a fortune designing medical software, but insists on bunking with Jamie — mainly so he can be Gyllenhaal's comic foil. Gad is the most relentlessly unfunny actor I've encountered since Jonah Hill. To be fair, however, he's given lines and routines (like masturbating to a sex tape of Jamie and Maggie) that are more cringe-inducing than anything else.

After his weak showing in the action flick Prince of Persia, Gyllenhaal is back in his comfort zone as the smooth-and-eager Jamie. But his character, like Hathaway's Maggie, is so well-worn and poorly written that we have little interest in watching how love will inevitably transform him from a selfish opportunist to a caring young man.

Although set in the 1990s, Love and Other Drugs has a late-'60s, early-'70s vibe. Two stars from that era, George Segal and the late Jill Clayburgh, even turn up in cameo roles as Jamie's parents. Zwick goes so far as to rip off the classic final sequence in The Graduate so blatantly that we must charitably assume it's meant as an homage.

As for Zwick’s other intentions, perhaps he meant this film to contrast the way the pharmaceutical companies devote their research and marketing to minor but profitable drugs like Viagra, instead of to ones that might alleviate or cure serious diseases like Parkinson’s. Or something like that. All I know is, by the end of this bummer of a movie not even Zoloft is likely to lift your spirits.

Love and Other Drugs is in theatres now.

Martin Morrow writes about the arts for CBC News.