Christopher on “The Sopranos” had a heroin addiction. And arguably, Tony had one to food…
Melrose Place: Allison was an alcoholic and she dated a sex addict for a while. Kimberly was addicted to crazy.
Bleeding Gums Murphy was addicted to the Fabrege Eggs.
Michael Garibaldi, Security Chief on Babylon 5, was an alcoholic, although on the wagon. In the fourth season he fell off in spectacular fashion, and managed to climb back on again.
Has there ever been a bigger addict than Frank Gallagher from Shameless (strictly speaking, not a sitcom, but very funny)?
He fell off in the 5th season, actually. In the 4th season, he was kidnapped, brainwashed, and forced to betray his friends and further the goals of his archnemesis, Alfred Bester.
But he stayed sober the whole time. 
Also on Babylon 5, Dr. Franklin, the station Medical Chief, was addicted to Stims, which he had started using because the station’s Medlab was understaffed and overworked, especially with various wars breaking out in nearby space.
The Wire, for the win. One of my favorite scenes in all of The Wire was in season 5 when the FBI profiler’s profile of a supposed serial killer actually describes McNulty to a tee basically, including his functional alcoholism. Also Bubbles and a bunch of course.
Yeah, they always work so hard to have a logical setup for those segues… 
and Bulldog. Other male sex addicts include Dan Fielding on Night Court, Sam Malone on Cheers, Fonzie on Happy Days, Charlie on 2 1/2 Men and many more men who will have sex with anybody who can trip them and beat them to the ground.
Are we treating anyone who enjoys frequent sex in a sitcom situation as a sex addict? Or does having flexible morals regarding sex come into play. The only one that sounds like it may be a true addiction is the Girlfriends example, but I have never watched that show.
Wife: I don’t like spam!
Man: Sshh, dear, don’t cause a fuss. I’ll have your spam. I love it. I’m having spam spam spam spam spam spam spam beaked beans spam spam spam and spam!
Vikings: Spam spam spam spam. Lovely spam! Wonderful spam!
I don’t think enjoying frequent sex = sexual addiction. But I think someone who makes repeated passes at her platonic friends and who becomes visibly antsy for no reason other than not having had sex in few days, and who then goes off, masturbates, and returns calmer, can be best described as not entirely in control of her sex drive.
There was an episode of MASH where one of the docs [not Pierce, though] was taking uppers of some kind so he could stay on the job and ended up becoming a jumpy overwrought twitch case.
And of course there was the famous episode of *Taxi *where Latka went into business selling cookies made from the “secret recipe” one ingredient of which, unbeknownst to everyone, was cocaine.
On HBO’s* Larry Sanders Show*, it seemed like most of the fictional Larry Sanders Show’s cast and crew were drunks, dopers or both.
And speaking of HBO, according to OZ there is so much dope freely available in the joint that I wouldn’t mind doing time in Em City myself.
WKRP’s Dr. Johnny Fever was obviously on something.
WKRP had the famous cocaine episode, and Barney Miller had the funniest of them all, the hashish brownies. “Mushie, mushie.”
Yeah, Larry was addicted to prescription drugs for a while (painkillers, I think). Arthur was clearly an alcoholic, but also clearly the kind that would say that “AA is for quitters.”
However, while Phil and other writers who came and went were variously high on various things, I don’t know that we ever had clear indications of addiction. I don’t think there’s any evidence that Hank was ever addicted to anything.
I don’t think everybody on a sitcom who enjoys frequent sex is a sex addict. I mean, it’s clear on The Golden Girls that all three of them have regular boyfriends and enjoy a pretty healthy sex life, but Blanche’s whole life seems to revolve around sex. Every story she tells is about sex. Everything she does can be traced back to a single motive. It’s always played for laughs, of course, but if you knew somebody who can’t have a conversation without making it about sex, who frequently “zones out” because she’s thinking about sex, who’s relationships all come down to sex, it points to a problem. I think Dan Fielding and Sam Malone have similar characterizations.
There are plenty of “players” in sitcoms, and even people who seem to enjoy regular sex, who I wouldn’t consider a sex addict. Both Tony and Bobby on Taxi were popular with the ladies. Frasier had several relationship son Cheers and Frasier. Drew had several relationships on The Drew Carey Show. Carla clearly had the proof that she enjoyed sex, but i wouldn’t argue she’s a sex addict.
He was also just about the only one of the major characters who ever came across as even a wee bit likeable, IIRC, and he was definitely portrayed as the only competent and reliable person on Larry’s staff .
It’s been such a long time since I saw that show that I can’t quite remember: Phil was the skinny obnoxious asshole writer, right, as opposed to Whazzizzface, the pudgy obnoxious asshole writer? ISTR a bit that would come up in various conversations every now and then about one of the duo being a crack fiend. Again, I haven’t seen that show in donkey’s years, or even thought about it before I posted in this thread, so my memory of it could be an utter bollix for all i know.
Dexter Morgan from Dexter, who I didn’t want to like but did, has an addiction to killing people.