Functional Addict

""Just cause you got the monkey off your back doesn't mean the circus has left town.""

- George Carlin

Because Drugs Are Bad, the world of fiction is famous for treating drug addicts as feeble, broken people living in disheveled apartments (or in a worst scenario, homeless) and constantly muttering to themselves. However, there has been a general trend lately towards portraying addicts in a more positive light. These drug users, with addictions just as serious, can lead very normal lives, at least to the strangers on the street. They can wake up in the morning, go to work, have a family, and interact socially without any noticeable problems, as long as they are getting their "fix" when necessary.

Simply put, the addiction does not rule this person's life. Typically, this kind of addict can go long periods of time without getting their "medicine" and doesn't depend on their drugs as a "crutch". Often, this is because they can always get the drug when they need it or have the willpower to keep themselves from getting out of control.

In Real Life these kinds of addicts can go their entire lives without ever becoming dysfunctional. It isn't real likely, but it can happen. Fiction, on the other hand, almost always treats them as ticking time-bombs, slowly working up to the one event that will send them over the edge. While crossing the line into dysfunctional territory definitely happens in Real Life as well, the key difference is that fictional sources treat this as inevitable.

Could be justified because fiction typically involves putting characters through unusual, dramatic and stressful situations which does increase the likelihood of an addict becoming dysfunctional. Also conservation of detail comes into play. Its usually not worth mentioning that the character has an addiction if it plays no role in the plot and tells us nothing important about the character.

It's common for none of the other characters in the work to even know that there is an issue until it gets worse. It is also commonly used as The Reveal for a particular character on a Very Special Episode, where it is revealed they have been a functional addict throughout the series and are now coming to terms with it.

Compare Dark Secret, for characters with any kind of sinister secret in hiding, and Drugs Are Bad, for all forms of fiction dealing with drug abuse.

Anime and Manga

 * Hyakujitsu no Bara: Klaus exhibits the Descontructed form of this trope. He is implied to have been addicted to morphine in the past, so that once he is injured and needs it to help enhance his performance it's not very effective and he has to increase dosages. As one would expect, he doesn't stop using it after that and it's still up in the air whether he'll be able to curb the addiction again or not.

Comics

 * In Cruelty, Reis Northcotte's mother is definitely dysfunctional, but Reis himself fits the bill. The facade is beginning to crack, however.
 * Despite his far more well-known breakdowns, Tony Stark actually spent a lot of time beforehand as a functioning alcoholic. Of course, as typical of works of fiction, that went downhill so steeply that he slammed straight into rock bottom. Hard. Granted, Tony's gone through a lot of awful shit, so his descent into full-blown alcoholism wasn't unjustified.

Film

 * Carlitos Way: Sean Penn's character David Kleinfeld
 * The Expendables: Gunnar is heavily suggested to be a junkie (a heroin addiction, presumably, based on the typical understanding of the word "junkie", but his exact addiction is a mystery), which heavily clouds his sense of better judgment and seriously afflicts his personality, yet he was still able to take on Ying Yang, and would have beaten him in one-on-one combat had Barney not interfered.
 * Ghosts of Mars: Melanie Ballard (Natasha Henstridge) is a drug addict, but manages to hold down a job as a police officer.
 * Minority Report: John Anderton has become addicted to "Neuroin" as a means of dealing with the loss of his son . He is able to hide this from all but his closest acquaintances, and it does not seem to hinder his ability to function as a cop. It's implied that New hEROIN is specifically designed to produce functional addicts.
 * Requiem for a Dream: All the characters begin their addictions completely functional, and most of them are arguably functional for almost the entire film.
 * Tropic Thunder: Jack Black's character Jeff Portnoy.
 * Obviously an Expy of Chris Farley.
 * The title character in Bad Lieutenant Port of Call New Orleans. To the nth degree, and typically with hilarious results. He's still a good cop, and even a Badass, but always in a believable way (I.E. not an overblown action-movie way).
 * "Teardrop" in Winter's Bone. He's competent and level-headed despite being hooked on meth.

Literature

 * Sherlock Holmes is a cocaine addict, but there was nothing wrong with it back in Victorian times. He apparently needs his fixes only when there aren't any interesting cases to solve.
 * Sir Arthur Conan Doyle was actually ahead of his time when he had Watson give Holmes a tongue-lashing over his habit in Sign of the Four.
 * Although technically even Holmes fits into the "ticking time-bomb" trope: in one of the later stories (written after the harmful effects of cocaine had become more widely known), Watson mentions that Holmes' addiction had eventually gotten bad enough that it had started seriously interfering with his work, at which point he was finally persuaded to quit.
 * By all evidence, James O. Incandenza, Jr., of David Foster Wallace's Infinite Jest was one of these (for the Incandenzas)...until he became a straight-up alcoholic and ended up.
 * Tom Clancy's Jack Ryan has a heroin problem, acquired through a pain medication regimen after a gunshot wound. Clancy's been criticized for this plot element, as he's supportive of the War On Drugs and dismissive of real-life chronic pain victims.

Live Action TV
""I'm a functioning alcoholic, you know? And the trick is not to get hung up on the alcoholic but celebrate the function part of the sentence.""
 * 24: Jack Bauer battles a heroin addiction after having to go under a cover as a Junkie just before season 3, but remains functional.
 * Southland: John Cooper is originally a functional addict, but
 * Dexter: Obviously not addicted to a "drug", but still battles with an addiction of sorts and maintains a "normal" lifestyle.
 * Played with, however, when Dexter is forced to go to NA, and uses his "addiction" to give his presence authenticity.
 * Heroes: Exaggerated with heroin addict Isaac Mendez, who is actually most functional when he is using heroin.
 * House: Prior to season 6 and, Dr. House bounced between functional, barely functional, and "holy-crap-I-need-my-Vicodin-right-now".
 * And late in season 7,
 * Law and Order Special Victims Unit: A replacement ADA is eventually revealed as a functioning alcoholic. She's able to disguise her behavior by being a hardass, but eventually she gets so out of control that she's forced to take a breathalyzer test in the middle of a trial and is subsequently disbarred... or rather, suspended. She returns the following season, attending AA meetings and overall putting in a really solid effort not to drink. Ironically, she's actually nicer when she's sober, even though irritability is an extremely common withdrawal symptom.
 * The Wire: Jimmy McNulty is a particularly believable example; hard-drinking and described by his best friend as "an emotional train-wreck of a human being", he clearly has many issues. While he is obviously alcoholic, it's not until season 5 that his alcoholism is explicitly called such (it mostly gets accepted as typical "cop" behaviour), but in a scene where the FBI are investigating . The FBI only listens to a short piece of  McNulty talking, but they use it to nail his personality almost exactly, describing him as an arrogant, high-functioning alcoholic. McNulty is visibly shaken by how accurate they are, especially given that he was loudly proclaiming the inaccuracy of FBI profiles not a minute earlier.
 * What about Bubbles? I mean, sure, the guy had quite a run of bad luck as the series progressed, but on an average day, he functioned just fine. In spite of how much some police underestimated and even dismissed him, he provided invaluable information and aid on many occasions. In the meantime, he was adept at scrounging up enough money to pay for his drugs through some ingenious scams, good with math, and ran a modestly successful business from a shopping cart for a time.
 * Bubbles is still a homeless junkie, despite all that. He has a lot of intelligence and ability but he only ever uses his skills to get more dope, and it's been shown several times that he completely falls apart when he can't feed his habit.
 * Leverage: Discussed by Nate:


 * Nurse Jackie is a functional addict to Oxycodone.
 * Will and Grace: Karen's complete addiction to pills and alcohol is a Running Gag, but she is entirely functional and coherent in her daily life. Oddly, not lampshaded at all in the episode where Will gets addicted to pain pills.
 * Played with in Dark Angel. A flaw in Max's engineered genetics means she has tryptophan deficiencies. Without large regular doses, she has crippling muscle spasms. Because of the state of America After the End, the stuff is expensive and hard to come by - though not quite as much as the steady supplies of chocolate, milk, yogurt, red meat, eggs, fish, poultry, and/or peanuts she'd need to get by without supplements. Because she keeps her condition a secret from her friends, they think she's addicted to recreational drugs and throw away her pills before even confronting her. It comes across as kind of a dick move, though it doesn't help that she won't even explain herself even when they stage an intervention for her.
 * Wait, she's dependent on tryptophan? The one that causes depression and pellagra (no muscle spasms there) when deficient?
 * You could make the argument that just about every main character on MASH is one of these. However, in one episode Margaret catches an old friend drinking during surgery and busts her. The withdrawal symptoms she goes through are...a bit disturbing.
 * Jesse from Breaking Bad starts out this way, mainly a pot smoker who occasionally dabbles in meth while still functioning close to normal,
 * Doctor Stephen Franklin on Babylon 5 is addicted to Stims during the third season, having started on them in the second season to keep up with the crushing burden of running an understaffed hospital and dealing with the many crises that occur on the station. When he nearly gets a patient killed due to being strung out from lack of rest and having dangerous amounts of the stuff in his system,
 * It is implied in the fourth season that Commander Ivanova is a functioning alcoholic, doing double-shots of vodka to try and sleep at night after
 * Justified: Detroit mob lieutenant Robert Quarles pops Oxy pills like candy, but he's still shown to be a cunning and ruthless villain.

Newspaper Comics

 * Doonesbury: Duke has consumed an enormous amount of alcohol and drugs throughout his life, in accordance with the Hunter S. Thompson caricature he was originally. While few of his many schemes and high-profile jobs have proved successful in the end, that hasn't been due to Duke's substance abuse so much as his arrogance, jerkassery and poor judgment even when sober.

Video Games

 * The Elder Scrolls Four: Being turned into a vampire could be considered this. The Player Character is just fine as long as he feeds once every few days.
 * Heavy Rain: Norman Jayden is apparently a functional addict of Triptocaine, though he can die from overuse.
 * The Templars of the "Dragon Age" series are essentially this. They get their anti-magic powers from lyrium, which is extremely addictive. All active-duty templars are functional addicts, but for every one of them, there's several for whom the years of enforced lyrium dependency have lead to becoming brunt-out shells.

Web Comics
"Schtein: I sometimes take amphetamines. You know, to stay alert...but that's more of a casual use thing...Um, then...sometimes I take sleeping pills. You know, the speed sort of keeps me awake. Maybe a little pot, and if someone offered me coke at a party I wouldn't exactly say no, uh...Spent as entire weekend when I was nineteen tripping balls on Ayahuasca...that's not important though, is it?"
 * String Theory: Dr. Schtein, without a doubt.

Western Animation

 * Futurama: Bender is essentially a commentary on functional alcoholism, as he literally needs alcohol in order to function, or else his fuel cells run dry, even though it makes him surly and he could actually survive on mineral oil.
 * Futurama robots could be an inverse; without alcohol, they get uncoordinated, have difficulty speaking, and are prone to erratic behavior. In other words, sobriety is to robots as drunkenness is to humans. Also, alcohol doesn't make Bender surly, he's always like that; now, having to drink mineral oil instead of liquor, that makes Bender surly.
 * Arguably, Homer from The Simpsons is one, but Depending on the Writer, this can vary greatly.
 * Dr Venture on The Venture Brothers is described by the creators of the show as "an addict, not a junkie.". He needs the pills to function (and take care of his various neuroses) but never is portrayed as pathetic because of that, more as a side-effect of why he's REALLY pathetic.

Real Life

 * While generally not vilified, coffee (caffeine) and cigarette (nicotine) addicts count, in addition to common place things such as sugar, salt, and fat, all of which the body naturally craves.
 * Not to mention some things so integrated into society that addiction is the norm, such as easy telecommunication, the Internet, social media, and so on. Drawing a distinct line between addiction and necessity however is hard, meaning only severely dysfunctional addicts are acknowledged as such.
 * The fact that you can hardly get through a television or internet presentation about a vaguely collected concept of "cyber-addiction" without any number of advertisements for Yahoo, Facebook, Google, Twitter, etc. goes to show that the popular concept of where the levels of "hobbyist", "functional addict" and "non-functional addict" seem to always lag a bit behind the research. Just take a look back to alcohol advertisements of the 80's and early 90's, and before that, the characters of family shows such as Lassie and The Flintstones taking breaks to advertise cigarettes among other wares.
 * Theodore Dalrymple's Romancing the Opiates, among other interesting facts, describes studies in which people with opiate addictions were able to maintain jobs for years, quite sufficient to maintain their habits.