Poor Santa! According to the quartet of zanies on parade in Spiked Eggnog, this year’s version of Centastage’s The Xmas Files, the weight-challenged senior citizen with a penchant for dressing in red has his problems. He’s lost his shirt in the stock market, the elves and the reindeer are unionizing, and Harry Potter is treading on his tail, making him exchange the cup of kindness for something stronger. And the letters he barks into his dictating machine to be sent to kiddies around the world are certain to be banned at Boston’s city limits because of their language and nasty intent.

So it goes with the beloved Christmas customs that get sent up by writer-performers Jan Davidson, John Kuntz, Rick Park, and Julie Perkins, who turn a collective, sardonic eye on our holiday habits in this fast-paced revue. Whether it’s a black-hearted mime version of the Virgin birth or the Bette Davis flick All About Eve performed by the second grade at St. Mary’s School as a Christmas pageant, the gloves are off and the actors come out swinging.

Dressing in drag is one predominant theme — indeed, it’s the tie that binds the trio of longer sketches that anchor the revue: " Santa’s Angels, " " All About Xmas Eve, " and " 4 Girls 4. " Kuntz is simply stunning in a bright orange jumpsuit topped by a Goldilocks wig; he’s rivaled only by Park in a floor-length silver-spangled skirt and tube top with metallic hearts placed over each boob, courtesy of costume designer Nicole Lyons. Although no one is credited with the hysterical assortment of wigs that enhance each costume change, K-Mart comes to mind.

Like all such enterprises, this one has its ups and downs — from the star atop the on-stage (plastic, of course) Christmas tree to the mattresses slung on the floor for a British teeny-boppers’ slumber party. The sight gags are more consistently on target than the lines — imagine Kuntz as a dumb-bunny blonde on a skateboard with a life of its own. Much of the humor comes from the quick changes that are in themselves a bit of a holiday miracle given the cramped backstage quarters of the BCA’s Black Box.

Kuntz also scores as a lounge-lizard vocalist singing " I Don’t Remember Christmas, " in which he denies having a broken heart; he’s accompanied on a miniature keyboard by his mother (Davidson), who hunches her shoulders in time to the music and rolls her eyes in maternal bliss at her son’s performance. Park nails the pretensions of the Brits who think they own the upper crust in " Santa’s Angels, " and Perkins is terrific as the bitchy parochial-school girl diva in the Kuntz-written " All About Xmas Eve. " Kuntz’s " All I Want for Christmas . . .  " has Santa looking for 50 ways to lose his lover, who turns out to be the Tooth Fairy (Perkins in a strapless pink tutu and wings); a rewrite may be in order to develop this promising situation. Park’s playlet " Santa’s Angels " and his finale, " 4 Girls 4, " are spoofs of two of the most familiar of female sisterhoods: the girl-detective squad and the best-friends-forever schoolgirls (so familiar from the Malory Towers boarding-school books by Enid Blyton). The stage picture is particularly potent in " 4 Girls 4, " which puts its nubile foursome in identical nighties as they cavort through a pajama party while wondering who has " done it " and with whom.

And if the visuals deliver more surprises than the dialogue in this review, never mind. Under-spiked eggnog is better than none at holiday time, at least as offered by these consummate clowns.