One of these tools is the nicotine patch, a type of nicotine replacement therapy that works by releasing a measured dose of nicotine into the skin, helping to wean smokers off their nicotine addiction and lessen the effects of nicotine withdrawal. Here’s what you need to know about trying it for yourself.

Where Can I Find a Nicotine Patch?

Before the Food and Drug Administration approved the over-the-counter sale of nicotine patches in 1996, they were available only by prescription; now you can buy a supply at a wide variety of stores, for about $4 a day. Most nicotine patches are made for 24-hour use, says Humberto Choi, MD, a pulmonologist at the Cleveland Clinic. But some people may decide to take the patch off before they go to bed, so they wear it only around 16 hours a day. Leaving the patch on for the full 24 hours can help provide you with a steady dose of nicotine, but you might be more likely to experience a side effect like skin irritation, too. The trade-off is that some people who don’t wear the patch overnight may experience more cigarette cravings in the morning.

The Right Way to Apply a Nicotine Patch

A nicotine patch looks much like an adhesive bandage and comes in a variety of sizes. You’ll put it on in the morning, on a clean, dry, and relatively hairless part of the body between the neck and the waist — for example, on the upper arm or the chest. The patch should be changed daily, and when you apply a new one, be sure to choose a different location to avoid any related skin irritation. Once you apply a nicotine patch, you’ll wear it continuously throughout the dosage period. Because it takes a few hours for the nicotine in the patch to seep into the bloodstream, says Dr. Choi, you might want to combat any immediate cravings with a piece of nicotine gum or a nicotine lozenge. Nicotine patches are generally used as part of an eight-week smoking cessation program, which may follow this pattern:

Weeks 1-4: You’ll wear a nicotine patch that delivers a strong dose of nicotine — for example, 15 to 21 milligrams (mg) per day.Weeks 5-8: You’ll switch to a weaker patch, one that may deliver 5 to 14 mg per day.

Side Effects of the Nicotine Patch

Most smokers get real relief from the nicotine patch — but they can also experience some side effects. These may include:

Skin irritation Some people’s skin may become irritated under the patch. Choosing a new skin site each day usually helps alleviate this problem; if it continues, you can consider switching to another brand of patch.

Sleep disturbances Some people using the patch report disruptions to their sleep, such as vivid dreams, insomnia, and other disturbances. If your sleep is still affected after three or four days of using a nicotine patch, try taking the patch off after 16 hours to give your skin a rest.

Racing heartbeat and dizziness If this occurs, stop using the patch immediately and talk to your doctor about switching to a lower-dose patch. According to a research review published in 2012 by the Cochrane Collaboration, nicotine replacement therapy doesn’t increase a smoker’s risk of having heart problems if he or she has a history of heart disease. However, if you do have a history of heart disease, be sure to use a nicotine patch under your doctor’s guidance.

Pain and nausea This includes headaches, muscle aches, and vomiting.

Choi cautions, though, that some of these symptoms may not be due to nicotine replacement therapy but to nicotine withdrawal itself. So be sure to talk to your doctor about the symptoms you’re experiencing; he or she can help you pinpoint the cause. Additional reporting by Maria Masters