uitting smoking isn't easy. More than 70 percent of smokers say they want to quit, yet only 5 to 10 percent are successful in any given attempt, according to the American Cancer Society. Despite these odds, more than 46 million Americans have managed to quit smoking for good, helping to decrease (or even eliminate) their risk of developing a range of serious health conditions.

Smokers have more tools at their disposal than ever to help them kick the habit, including medications, counseling services, and self-help materials. And many have found success through nicotine replacement therapy (NRT), the use of nicotine delivery methods to help ease withdrawal symptoms and cravings caused by the loss of nicotine from cigarettes.

Wondering if NRT could help you or someone you love quit smoking? Here, the lowdown on the five forms approved by the U.S. Food and Drug Administration (FDA):

The Method: Nicotine Patch

Usually worn on the arm, the nicotine patch releases nicotine into the body through the skin. The patch is available in several doses, or "steps," so that smokers can gradually wean themselves off nicotine completely. For example, smoking a cigarette delivers roughly 1 mg of nicotine, so someone who used to smoke a pack a day (20 cigarettes) may start with the step one patch, which delivers 21 mg throughout the day. Someone who smoked less may begin at a lower dose.

The Pros: The different levels of nicotine patches available allow smokers to choose the appropriate one for their smoking habits. By gradually working down the levels, they're able to cut down on the amount of nicotine until the addiction dissipates completely.
The Cons: Because the nicotine patch slowly releases nicotine into the bloodstream, the level of nicotine can't be adjusted if the person happens to have a strong nicotine craving. It also may not be suitable for people with sensitive skin.
Side Effects: Possible side effects include skin irritation at the site of the patch, dizziness, nausea, vomiting, racing heartbeat, sleep problems, and headaches. Side effects vary, depending on the dose of nicotine, the person's level of skin sensitivity, how long the patch is used, and how it's applied.

The Method: Nicotine Gum

This special chewing gum delivers nicotine to the bloodstream through absorption by the tissues of the mouth. The gum is chewed until it's soft and gives off a tingly sensation and/or peppery taste. Then it should be pressed between the cheek and gums, known as "parking." When the tingling sensation stops, the gum is chewed again and then parked in a different place in the mouth. This process should be continued until the gum is depleted of nicotine (about 30 minutes). Nicotine gum is available over-the-counter, in both 2 mg and 4 mg strengths. A person who smokes a pack or more per day or smokes within 30 minutes of waking up may need to start with the higher 4 mg dose. Nicotine gum is usually recommended for one to three months, with the maximum duration being six months.

The Pros: Nicotine gum allows people to control the nicotine doses their bodies receive. The gum can be chewed as needed or on a fixed schedule during the day, although no more than 20 pieces of gum are recommended per day. It's also a good choice for people who have sensitive skin and don't want to use a nicotine patch.
The Cons: Long-term dependence is one possible disadvantage of nicotine gum. In addition, the gum can damage dentures and dental prostheses.
Side Effects: Potential side effects of nicotine gum include a bad taste in the mouth, throat irritation, mouth sores, hiccups, nausea, jaw discomfort, and a racing heartbeat. Symptoms related to the stomach and jaw are usually caused by improper use of the gum, such as swallowing nicotine or chewing too fast.

The Method: Nicotine Lozenges

These smoking-cessation candies release nicotine as they slowly dissolve in the mouth. Eventually, the quitter will use fewer and fewer lozenges during the 12-week program until he or she is completely nicotine-free. Smokers can choose their dose based on how long after waking up they normally have their first cigarette.

The Pros: Because the nicotine is absorbed through the lining of the mouth (like the gum), it gets into the blood more quickly, and as a result, it reaches the brain much faster, sending the message that the body has enough nicotine.
The Cons: Biting or chewing the lozenge can cause too much nicotine to be swallowed quickly, resulting in indigestion or heartburn.
Side Effects: Possible side effects include nausea, hiccups, coughing, heartburn, headache, gas, and trouble sleeping.

The Method: Nicotine Nasal Spray

The nasal spray delivers nicotine to the bloodstream as it's quickly absorbed through the nose. It is available only by prescription.

The Pros: It relieves withdrawal symptoms very quickly and lets the user control their nicotine cravings. Smokers trying to quit usually like the nasal spray because it is easy to use.
The Cons: Because the person controls how much of the spray he or she uses, there's the potential dangers of using too much. In addition, those with asthma, allergies, nasal polyps, or sinus problems are usually discouraged from using this product.
Side Effects: The most common side effects can include nasal irritation, a runny nose, watery eyes, coughing, sneezing, and throat irritation.

The Method: Nicotine Inhalers

Introduced in 1998, these inhalers, composed of a thin plastic tube with a nicotine cartridge inside, are available by prescription only. When the person puffs on the inhaler, the cartridge emits a nicotine vapor. Unlike other inhalers, which deliver the majority of the medicine to the lungs, the nicotine inhaler delivers most of the nicotine vapor to the mouth. The recommended dose is between six and 16 cartridges a day, for up to six months.

The Pros: Nicotine inhalers are the closest thing to smoking a cigarette, which some smokers find helpful.
The Cons: At this time, inhalers are the most expensive forms of NRT available. According to the American Lung Association, the average cost of the nicotine inhaler is approximately $45 for a package containing 42 cartridges.
Side Effects: The most common side effects, especially when first using the inhaler, include coughing, throat irritation, and upset stomach.

When choosing a type of NRT, it's important to consider which method will best fit your lifestyle and pattern of smoking.

The Benefits of Quitting

Making the decision to stop smoking is one of the best things you can do for your health. According to reports from the U.S. Surgeon General, two weeks to three months after quitting, your circulation improves and your lung function increases. One year after quitting, your risk of coronary heart disease is half that of a smoker's. Five to fifteen years after quitting, your stroke risk is reduced to that of a nonsmoker. Ten years after quitting, your risk of cancer of the mouth, throat, esophagus, lungs, bladder, cervix, and pancreas decrease. And after 15 years of quitting, your risk of coronary heart disease is equal to that of a non-smoker. And it all begins with four simple words: "I want to quit."