Originally marketed as an anti-depressant drug, bupropion is available by prescription only. Its effectiveness as a quit smoking aid was discovered when smokers using it to treat depression also lost interest in smoking. People not planning to quit smoking found themselves stopping with relative ease. Nicotine withdrawal symptoms usually associated with quitting smoking were minimal.

While it isn't understood exactly how bupropion works, we do know that this prescription-strength medicine alters the brain's chemistry. The result is a reduced interest in smoking. Nicotine cravings are diminished, and often people find it easy to quit because smoking loses its appeal.

In 1997, the FDA approved Zyban to be used as a quit smoking aid, and since then, bupropion has become a popular method to help smokers kick the habit. Bupropion, when used in combination with other nicotine replacement therapies (NRT's), such as the nicotine patch or nicotine gum, increase the chances for long term success with smoking cessation.

Zyban must be prescribed by your doctor. Typically, the recommended dosage is one 150 mg pill once a day for the first 3 days. After that, the dosage is increased to one 150 mg pill twice a day, 8 hours apart. It's a good idea to space your pills out so that the second pill of the day is several hours before bedtime as bupropion can have a side effect of insomnia.

Never take an "extra" dose to catch up for missing a pill. Wait and take the next pill at the normally scheduled time. Most doctors suggest using bupropion for 7 to 12 weeks to achieve the best results for smoking cessation. Never stop taking this drug abruptly, or without consulting your doctor first.

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have any new or worsening symptoms such as: mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), more depressed, or have thoughts about suicide or hurting yourself.

Call your doctor at once if you have a seizure (convulsions) or fast, uneven heartbeats

Less serious side effects may be more likely to occur, such as:

• nausea, vomiting, constipation, dry mouth;
• mild itching or skin rash, increased sweating;
• confusion, dizziness, tremors (shaking);
• appetite changes, weight loss or gain;
• headache or migraine;
• loss of interest in sex.