Forget doctors, cops and lawyers: Nursing is the hot profession on TV.

Jada Pinkett Smith stars as one in “HawthoRNe,” a series that debuts on TNT next week. And half the network series bowing in the fall seem to be built around nursing staffs.

But first up, we have Edie Falco in the splenetic comedy “Nurse Jackie,” premiering tonight at 10:30 on Showtime.

What’s with the sudden proliferation? Maybe television producers are finally figuring out that while doctors get the money and the attention, it’s the underpaid nurses who do all the work.

As the title character in “Nurse Jackie” says to a newbie, “The doctors are here to diagnose, not heal. We heal.”

Everyone but themselves, apparently.

Jackie is one sick caregiver. She snorts stimulants in the morning (“a little bump to get me up and running”) and wolfs painkillers all day long.

She removes her wedding band at work because she’s pumping the hospital’s smitten pharmacist on a daily (sometimes hourly) basis for drugs.

Yet this high-functioning junkie brags about having quit drinking. “I like to have a clear head,” she says with puzzling righteousness. Or maybe that’s the Oxycontin talking.

Falco, who won three Emmys for her role as Carmela Soprano, is all business here, even adopting a boyish, off-the-ears hairstyle. She works at All Saints in Manhattan, the most dreary TV hospital since St. Eligius.

She’s one tough broad, castigating a talkative nursing student, “I don’t like chatty. I don’t do chatty. Quiet and mean are my people.”

Ah, but underneath that crusty surface, she’s the soul of compassion, agonizing over her patients, reassuring the afflicted, comforting the bereaved and punishing the wicked. Despite working insane hours, she still gets home on the subway in time to fix the school lunches for her two young daughters.

You’re getting the picture, right? Jackie is a tarnished saint, a personality type that is becoming an overused TV staple on shows from “House” to “24” to “Saving Grace.” Falco is such an appealing and convincing actress that she can pull off this tricky balancing act.

Unfortunately, she has little assistance. What makes “The Closer” work is that Kyra Sedgwick is surrounded by brawny scene-carriers.

Nurse Jackie? Not so much.

The show’s cast (including Peter Facinelli, Anna Deavere Smith and Eve Best) is more than capable. But with the exception of Jackie’s tart-tongued gay colleague Mohammed (“The Visitor’s” Haaz Sleiman), the characters are paint-by-numbers figments.

That leaves the leading lady to carry far too much of the load. It’s appropriate that Jackie never seems to get out of her work clothes.

In addition to lacking balance, “Nurse Jackie” is also trying a little too hard to be provocative. And its bleak moodiness, like the bitter pills Jackie constantly ingests, is tough to swallow.