Ask Dr. K: Various nicotine delivery methods help smokers quit

Cigarette smoke contains many different substances that damage the tissues of the body and increase the risk of cancer. But those damaging substances are not what make you addicted to cigarettes.

Nicotine, one of the many dangerous chemicals found in cigarettes, is what addicts you. It doesn’t damage your tissues; it just makes you want to smoke. Each hit of nicotine produces pleasure. But as nicotine leaves the body, you begin to experience uncomfortable withdrawal symptoms, and this prompts you to reach for another cigarette.

One type of quit-smoking medication is called nicotine replacement therapy (NRT). It delivers a low dose of nicotine into your bloodstream to ease or erase withdrawal symptoms. You start the nicotine replacement on the day you stop smoking. Instead of getting the nicotine your body continues to need from cigarettes, you get it from the replacement treatment. As your withdrawal symptoms decrease, you lower your dose, then gradually wean yourself off all nicotine, including NRT.

There are several forms of NRT. Some are available over-the-counter, others by prescription:

— Nicotine patches stick on your skin like a bandage. They supply a low dose of nicotine that gets absorbed through the skin and into your bloodstream throughout the day.

— When you chew nicotine gum, it releases a low dose of nicotine that is absorbed through your cheek and into your bloodstream.

— When nasal spray is sprayed as a mist into the nose, nicotine reaches the bloodstream within five to 10 seconds. This is the fastest way to relieve withdrawal symptoms.

— Puffing on a cigarette-shaped inhaler (sometimes called an e-cigarette) delivers a low dose of nicotine through the mouth, throat and lungs. You use the inhaler when you feel the urge for a cigarette.

— Lozenges supply a low dose of nicotine that gets absorbed into your bloodstream.

Two other quit-smoking medications do not contain nicotine; they act on the brain to decrease nicotine cravings, nicotine withdrawal symptoms, or both.

Varenicline (Chantix) and bupropion (Wellbutrin, Zyban) are prescription drugs. They imitate some effects of nicotine, cutting down on cravings and withdrawal symptoms. So if you slip and have a cigarette, you will experience less of a reward.

The U.S. Food and Drug Administration (FDA) has reported that both varenicline and bupropion may, in a few people, trigger thoughts of suicide or actual suicide attempts. Any person starting on these treatments, and their friends and family, should look for changes in mood and behavior.

Withdrawal symptoms are most intense when you first quit. Getting through your fifth or 10th cigarette-free day will be much easier than getting through your first.

Dr. Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK.com, or write: Ask Doctor K, 10 Shattuck St., Second Floor, Boston, MA 02115.