Bupropion chemical structure
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Zyban

Bupropion (amfebutamone) is an antidepressant of the amino ketone class, chemically unrelated to tricyclics or selective serotonin reuptake inhibitors (SSRIs). It is similar in structure to the stimulant cathinone, and to phenethylamines in general. It is a chemical derivative of diethylpropion, an amphetamine-like substance used as an anorectic. Bupropion is both a dopamine reuptake inhibitor and a norepinephrine reuptake inhibitor. more...

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History

Bupropion was first synthesized by Burroughs Research in 1966, and patented by Burroughs-Wellcome (later Glaxo-Wellcome, and, as of 2000, GlaxoSmithKline) in 1974. It was approved by the FDA in 1985 and marketed under the name Wellbutrin as an antidepressant, but clinical trials indicated that incidence of seizure was two to four times greater than other antidepressants and the drug was quickly pulled from the market. It was subsequently discovered that reducing the dose by about half greatly reduced the risk of seizures. Glaxo then developed a sustained-release (SR) version of Wellbutrin which releases bupropion hydrochloride at a slower rate. The SR formulation is taken twice a day, in order to further decrease the possibility of adverse side effects and seizures. It is also available in generic form (Bupropion SR). Extended Release bupropion, Wellbutrin XL, is the most recent formulation of bupropion and is taken orally once a day. Because of this altered mechanism of delivery and reduced dosing, incidence of seizures with bupropion is comparable to, and in some cases, lower than that of other antidepressants.

In 1997, bupropion HCl was approved by the FDA for use as a smoking cessation aid. Glaxo subsequently marketed the drug under the name Zyban to help people stop smoking tobacco by reducing the severity of craving and addiction/withdrawal symptoms. It can be used in combination with nicotine replacement therapies. Bupropion treatment course lasts for seven to twelve weeks, with the patient halting the use of tobacco around ten days into the course.

Bupropion is also being investigated as a weight loss drug.

Mode of action

Bupropion is a selective catecholamine (norepinephrine and dopamine) reuptake inhibitor. It has only a small effect on serotonin reuptake. It does not inhibit MAO. The actual mechanism behind bupropion's action is not known, but it is thought to be due to the effects on dopaminergic and noradrenergic mechanisms.

Pharmacokinetics

Bupropion is metabolised in the liver. It has at least three active metabolites: hydroxybupropion, threohydrobupropion and erythrohydrobupropion. These active metabolites are further metabolised to inactive metabolites and eliminated through excretion into the urine. The half-life of bupropion is 20 hours as is hydroxybupropion's. Threohydrobupropion's half-life is 37 hours and erythrohydrobupropion's 33 hours.

Chronic hepatotoxicity in animals

In rats receiving large doses of bupropion chronically, there was an increase in incidence of hepatic hyperplastic nodules and hepatocellular hypertrophy. In dogs receiving large doses of bupropion chronically, various histologic changes were seen in the liver, and laboratory tests suggesting mild hepatocellular injury were noted.

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Rising from the ashes: you've always smoked like a woman. Now you need to quit like one too. The latest research shows that your best shot at tossing tobacco
From Better Homes & Gardens, 11/1/03 by Kelly Garrett

It was so easy to start smoking. You and your friends took tiny puffs until your lungs could handle a full-out draw. You practiced holding cigarettes in ways that looked sophisticated. You felt mature beyond your years.

Soon, smoking became your own private pleasure; it was a way to relax in moments of stress, and something to hold on to when everything else seemed uncertain. You developed your own rituals around the slender white sticks--a few in the morning with a cup of good coffee, one or two while you were on the phone with your sister, a couple in the car to take your mind off a terrible day.

But, years later, when your lungs started feeling heavy and you panicked each time you forgot to pick up cigarettes at the store, you began to realize that this smoking thing wasn't all it was cracked up to be. And you wanted out.

Your cigarettes, though, had a different idea. When you tried quitting, the addiction screamed at you for weeks. And when the screaming died down, the whispering started: You're doing really well, it said. You can have one smoke now. Just one.

Frustrated, angry, and even desperate, you ask yourself: Will I ever be able to get off these things? The answer to that is easy--it's a resounding YES!

Now comes the hard part. About 95 percent of would-be quitters don't make it on any given attempt, and there's strong evidence that women have an even harder time of it than men. New research is recognizing that the entire smoking experience is not the same for men and women. As a rule, women smoke for different reasons than men do. They get pleasure from it in different ways. They value taste over strength. They light up with their own rituals. In short, women's relationship with those little sticks of rolled tobacco is unique--and powerful.

At the same time, the killer diseases that smoking promotes seem to prefer female victims, with women smokers taking on almost twice the risk of heart disease and lung cancer compared to their male counterparts. And the toxic chemicals in smoke even cause women to wrinkle more than men.

But take heart. The same research that is highlighting the differences in the way women smoke is also finding new woman-specific ways to help them quit. Look at it like this: If women smoke in their own way, shouldn't they stop smoking in their own way?

Indeed they should. There are plenty of for-women-only strategies for you to take advantage of next time you try to give up cigarettes. For example, you should know that your menstrual cycle provides a practical quitting opportunity you can use right away. New research has clearly shown that tobacco withdrawal symptoms and low moods--powerful early saboteurs of your quitting quest--are noticeably milder during the first half of the cycle.

That's key information when it comes to setting your quit date. Yet few women smokers ever hear about it, so they often miss out on the obvious advantage of minimizing the misery during the first two crucial weeks of abstinence. "If you have some control over the choice, it's better to quit in the earlier phase of your cycle," says Michele Levine, Ph.D., an assistant professor of psychiatry at the University of Pittsburgh Medical Center who conducts research on women and smoking.

Another surprising revelation is that nicotine, the addicting chemical in tobacco, doesn't seem to influence women's smoking habits as much as it does men's. In one study, investigators at the University of Pittsburgh surreptitiously varied the nicotine doses in volunteers' cigarettes and found that, compared to men, the amount of nicotine inhaled by women has little impact on their pleasure or on reinforcement (that is, on satisfying the habit). Even more important was the related discovery that nicotine replacement therapy--patches, gums, and inhalers--works less well for women, although scientists aren't sure why.

Does that mean you would be wasting your time with something like the patch? Not necessarily, but if you've used nicotine replacement therapy before and it was unsuccessful, you might want to try a different, very specific form of it next time. A clue to handling the situation comes from Nicotine and Tobacco Research, a recent landmark study by French scientists that followed the smoking-cessation efforts of 400 subjects for a year. They were about evenly split between men and women, and a variety of stop-smoking aides were used. The results confirmed that while nicotine dependence is generally lower for women, behavioral dependence is higher. That means, among many other things, that women tend to miss the ritual of lighting up as much as the nicotine hit.

This led the researchers to suggest a best-of-both-worlds approach: If you go for nicotine replacement therapy, choose the inhaler method, which (unlike the patch or gum) requires some behavioral action each time you use it. You have to take the small device out of your purse or drawer, lift the mouthpiece to your lips, and take a smokeless puff of pure nicotine--pretty much like lighting a cigarette. "The nicotine inhaler may be a good tool for women," says lead study author Dr. Abraham Bohadana, of the French National Institute of Health. "It not only provides nicotine craving relief but also seems to satisfy the 'hand-to-mouth' habit smokers are used to."

Remember that talk about behavioral dependence being high in women? A drug called Zyban may be a better way of dealing with that type withdrawal symptom. It's a nicotine-free, prescription-only medication that quells the urge to smoke and eases the withdrawal symptoms as you stop smoking. It helps both men and women--but women more.

Zyban may at first seem a strange candidate to be the preferred treatment plan for women smokers. Swallowing a daily pill obviously doesn't deal much with such behavioral dependencies as hand-to-mouth action. But Zyban does address a smoking-related consideration that's far more crucial to women than to men: mood.

Low moods, sometimes even symptoms of depression, haunt women's smoking-cessation efforts. They're a major reason why women are cursed with a higher relapse rate than men. Zyban often fixes that mood problem for women because it was originally manufactured as an antidepressant before researchers found that it also helped a lot of test subjects quit smoking.

It's still unknown precisely how Zyban works, but that lack of knowledge doesn't seem to affect this medication's ability to help women stop smoking. "What causes early relapse is withdrawal," says Kenneth Perkins, Ph.D., another University of Pittsburgh professor of psychiatry and a prominent smoking-cessation researcher. "But what is withdrawal? It's mostly feeling bad. So even if it's not clear exactly how Zyban works, it's an anti-depressant that can help you feel better."

As damaging as mood lows can be, almost nothing bedevils women's attempts to quit smoking more than weight gain--or, rather, fear of weight gain. Because, sad to report, the odds are that you're going to gain some weight while you're kicking the habit. Ten pounds is typical.

Those extra pounds don't hurt your stop-smoking effort, but worrying about them does. Weight concern, as the experts call it, is one of the top reasons women have a hard time quitting. It keeps many from even trying to quit in the first place.

Obviously, the solution is to start dieting as you stop smoking, right? Absolutely not! The old assumption among experts that weight-control guidance would benefit women is yielding to newer insights. "Going on a diet does not help," Levine says. "Either you won't quit, or you won't lose weight, or you'll end up five pounds overweight and still smoking."

The new advice? Don't fight the weight gain. Focus solely on not smoking. Sacrilegious as it sounds to accept extra pounds, it's the smart thing to do. "From a health standpoint, it's much more critical to stop smoking," Perkins says. "Moderate weight gain is not the end of the world. It's a small price to pay for the health gains of quitting smoking."

Levine and Perkins tested this new strategy by dividing 219 women smokers who wanted to quit into three groups. One group got diet advice, another received counseling to allay their concerns about weight gain, and the third group ignored the issue of weight gain. Those who learned to accept some moderate weight gain--whether they got counseling, advice, or ignored the issue--were far more successful in their quit efforts than the rest.

But here's the real eye-opener: The women who were counseled to not worry about added pounds ended up gaining less weight than even the dieters. In fact, those who focused on weight control not only were far less likely to quit smoking, they gained more than twice as many pounds (11.9 on average) then those who decided to let the pounds fall where they may (5.5).

"We're not saying go ahead and get fat," Perkins says. "We're saying shift the focus to accepting moderate weight gain. It's okay to have food cravings, but don't eat an entire cake."

Women also tend to understand that good social support is essential. "The most powerful way to do that is to have a role model, an ex-smoker telling you 'I quit, and you can too,'" says Edward Feil, Ph.D., of the Oregon Research Institute in Eugene.

Like-minded strangers can sometimes be even more helpful than friends or family. Research by Feil and his colleagues at the Institute found that the newly flowering online stop-smoking communities, such as Quitnet.com, are becoming valuable centers of social support and information. And so far, the main beneficiaries (and overwhelmingly so) are women.

The investigators set up their own stop-smoking Web site and signed on 600 smokers, the vast majority of them women. Everything that the researchers recommend you look for in choosing a site was included--a chat room for the all-important peer support, an ex-smoker staffer to monitor the chat room and bulletin board while also serving as a role model, and professional advice available in an "ask-the-expert" area.

The site was a winner. Of those users who responded to a follow-up survey three months later, fully one in three had quit.

The investigators had no intention of gearing their experimental stop-smoking site to women, but mostly women signed up and mostly women got the benefits. That may be for the best. "Women tell us that being with other women helps," Levine says. "There's something about not having any men around that lets the issues that concern women come to the surface--such as PMS, weight gain, bad moods, and missing the social aspects of smoking."

And, you know, there's probably an element of grace in that too. After all, you likely started smoking in the company of women. Why not quit in their company as well?

PROFILE OF SUCCESS

NANCY MORRIS

ETTERS, PENNSYLVANIA

Like a lot of women, Nancy started smoking around age 18. Also like many women, pregnancy inspired her to quit. For a bit.

"After my second pregnancy, postpartum depression set in," she says, "At least, that was my excuse." Then came eight or nine failed quit attempts.

The breakthrough finally came when Nancy hooked up with an Internet program sponsored by the American Lung Association called Freedom From Smoking, at www.lungusa.org/ffs.

Now, at 42, Nancy will soon be smoke-free for two years. While the program obviously helped, Nancy gives much of the credit to her online quitmates. "I probably learned as much from the people sharing techniques on the site's bulletin board as from the actual program," she says. "For example, if I got the urge to go out and buy a pack, I would first agree to make a list of five other things to do first. By the time I did the other things on the list, I no longer felt like smoking."

CATHY MILCHAK

GRANTS PASS, OREGON

The quit attempts were piling up after a decade of smoking. Then two things happened: Cathy's circle of friends changed, and she found herself feeling good-naturedly ostracized as the only one in the crowd who smoked. Also, her 30th birthday loomed, and she saw it as a milestone for real, honest-to-goodness redirection.

Cathy's chosen quitting strategy? Cold turkey. It's still the most common method women use to quit, as well as the most common method they use to fail. With Cathy it worked, but not without intense physical struggles, followed by extreme mental challenges. "It was hard when I was around people who smoked, it was hard when I was around alcohol, and it was hard when I was under pressure," she says. "My way of handling that was to lie pretty low for a while."

Today, she has seven smokeless years behind her, although she still dreams about cigarettes occasionally. "It's not like something I have to fight though," she says. "I know smoking again is just not an option."

TEOLA BAYMILLER

BERESFORD, SOUTH DAKOTA

It wasn't unusual for Teola to smoke her way through three packs a clay during her 43-year habit. About 10 years ago, her lungs began to Jail and she knew it was either stop or die. Yet quit attempt followed quit attempt.

"I was actually on oxygen treatment and smoking at the same time," she says. "The addiction is that insane."

Teola heard about The American Cancer Society's free Quitline program (800/227-2345) and jumped at it. She also started taking Zyban and using a nicotine patch. The three-pronged approach of pills, patches, and phones worked. "I can go for walks now. I can sing along in church," she says. "I have my breath back."

--Kelly Garrett writes from Mexico City, where relatively few women smoke.

COPYRIGHT 2003 Meredith Corporation

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