"Lovesick" is an undernourished romantic comedy that dotes on the alleged liberation of a bored psychiatrist, played by Dudley Moore, who kisses off his practice after falling in love with a patient. For practical purposes, Marshall Brickman's feckless screenplay depends on convincing an audience that the respectable, repressed shrink, called Saul Benjamin, can't and shouldn't resist a form of temptation at once adulterous and unethical, because the object of his infatuation, an aspiring playwright called Chloe Allen, is simply too precious to be lost.

If the premise sounds curiously familiar, it's because Dudley Moore has worn out the patent on the role of the suddenly, desperately infatuated middle-aged professional twerp.

Nevertheless, Brickman might have triumphed over the feebleness of his powers of invention if Chloe had been calculated for maximum appeal, erotic or spiritual and preferably both. Elizabeth McGovern proves such an insipid image of femininity as this misbegotten sweetheart that the doctor's infatuation looks bewildering and embarrassing rather than inspiring. Benjamin's boredom seems to provoke a crush on a peculiarly school-girlish young woman whose charms are easily resistible to the extent that they're even faintly discernible.

The Bo Derek character in "10" may have left something to be desired as a soul mate for Moore's smitten composer, but audiences were never perplexed over the source of his erotic obsession with her. In the recent unsuccessful tearjerker "Six Weeks," Moore played a political candidate whose devotion to a dying adolescent girl was rationalized to some extent by the elfin beauty of the juvenile actress Katherine Healy. Indeed, the paternal attachment to Healy made far more sense than Moore's alleged romantic attraction to McGovern in "Lovesick," which collapses from a shocking lack of credibility the moment the heroine makes her entrance.

While Brickman belabors a wanly smug form of New York urban facetiousness that he and Woody Allen more or less exhausted in "Annie Hall" and "Manhattan," Moore does a colorless refrain on his "10" number and McGovern turns into a puffy-cheeked juvenile while ostensibly playing her first adult role. The setback to her career is potentially damaging; she seemed vastly more attractive and skillful, not to mention more grown-up, as a high-school girl in "Ordinary People."

Brickman also seems to mistake "Lovesick" for a definitive satiric kiss-off of psychiatry, which hasn't been treated with automatic deference for quite a few years now.

It amuses Brickman to pretend that the profession is a waste of everyone's time and that this observation is so widespread that even Freud himself would endorse it with droll equanimity. To document this presumption, he casts Alec Guinness as a Freud who materializes from time to time to kibitz with the daydreaming hero insultingly cheeky of Brickman to fob off his own facetious opinions as nifties from the mouth of Freud himself. Either you've got the conviction of your ridicule or you don't. It's intellectually dishonest--and timorous--to invoke The Founder himself as a voice of authority for wisecracking comments about the debatable state of the methods he pioneered.

Brickman doesn't even bother to keep the wisecracks logically consistent. At one point it pleases him to solicit a laugh by having Freud remark, "I try to keep up with the literature." A bit later a laugh is predicated on the notion that Freud is ignorant of the term "Freudian slip." Brickman scrapes the bottom with his cutesy-pie mouthpiece Freud in a scene where he offers this nugget of wisdom while observing Saul and Chloe hit the sack: "It's very simple . . . Mother Nature steps in and reminds us what we really are--animals. This is my great lesson. Take it or leave it."

Ironically, "Lovesick" is compromised by Brickman's take-it-or-leave-it approach to dramatization. A mood of blithe dismissal runs from one end of the scenario to the other. For example, the opening sequence is contrived to brush off Saul's patients as so many neurotic time-wasters. The funniest performer in the movie, Wallace Shawn as a fellow analyst whose infatuation anticipates the hero's, is prematurely eliminated. Given the insistent pointlessness of Saul's practice, there's never a compelling illusion of conflict between career and romance.

Even the little technicality of his marriage is casually canceled out by the revelation that his wife was deceiving him first (with a bluntly carnal painter played very likably by Larry Rivers). The possibility that other men might be serious rivals for Chloe's affections is rendered nonsensical by reducing the threat to a single fatuous actor, played by Ron Silver. Among other telltale signs, Silver's character betrays his phoniness by referring to Shakespeare and Chekhov in absurdly patronizing terms. How this defect differs from Brickman's own chummy invocations of Freud is impossible to guess, but it appears that what qualifies as outrageous presumption in a minor character is miraculously transformed into clever presumption in the author. "Lovesick" wants to be a funny cinematic valentine, but it withers inside the confines of New York comic snobbery.