Nicotine replacement therapy: Proven aid to quit smoking with less struggle

Quitting smoking is not an easy task for all smokers. When a smoker stops smoking, his/her body experiences strong nicotine cravings and withdrawal symptoms, which lead some people to relapse. Nicotine replacement therapy (NRT) is a well-evident, safe and effective aid for quitting smoking. It provides a safe and low dose of nicotine replacing smoking, helping smokers to gradually break free from nicotine and tobacco dependence, and making the quitting process easier.

Common forms of NRT include nicotine patches, lozenges and gum. All are widely available through smoking cessation services in Hong Kong. Those wish to quit smoking can contact the Integrated Smoking Cessation Hotline 1833 183 of the Department of Health to acquire more information about NRT and other cessation methods, and receive appropriate smoking cessation services.

Watch the video to learn more how to use nicotine replacement therapy properly:

The mechanism of nicotine addiction

Smoking makes nicotine to rapidly enter the brain and bind to specific nicotinic receptors, triggering the release of large amounts of dopamine. This creates a temporary sense of pleasure for smokers. Chronic smoking causes an increase in the number of nicotine receptors in the brain and leads to tolerance towards nicotine stimulation. As a result, smokers crave for more nicotine and need increasingly higher doses to achieve the same level of pleasure.

Learn more about the mechanism and harms of nicotine addiction.

Nicotine replacement therapy helps you through the adjustment period

Instead of smoking, NRT delivers nicotine in lower, controlled, and relatively safe doses. By using NRT, nicotine is slowly released into the bloodstream and steadily binds to receptors without causing excessive stimulation, alleviating withdrawal symptoms and avoiding the substantial health risks associated with tobacco use. Gradually, NRT helps the brain adjust to lower levels of nicotine, ultimately freeing smokers from nicotine dependency and sustaining smoking cessation in long-term.

A systematic review of 133 studies involving over 64,000 participants found that NRT can increase the long-term quit rate (quit for at least six months) by about 50% to 60%. Another systematic review analyzing 14 studies with over 11,000 participants found that using combined forms of NRT increases long-term quit rates by about 25% compared to using a single form.

Types of nicotine replacement therapy

NRT is available in various forms and dosages to cater the needs of adult smokers seeking to quit. See the table below for details.

In Hong Kong, all NRT products are classified as pharmaceutical products and are regulated under the Pharmacy and Poisons Ordinance (the Ordinance). Currently, there are 14 registered NRT products in Hong Kong. Among these, six nicotine patches, one nicotine lozenge and six nicotine gums are classified as poisons under Part 2 Poison of the Ordinance. They are regulated as over-the-counter medicines and are sold in authorized pharmacies or medicine stores. One nicotine oral spray is classified as a poison under Part 1 & Schedule 1 Poison of the Ordinance. It can only be sold in pharmacies in the presence and under the supervision of a registered pharmacist, and relevant sales records must be kept.

Anyone plans to quit smoking may obtain free nicotine patches, lozenges, and gum through designated smoking cessation service providers. They may also receive guidance from professional smoking cessation counsellors on selecting appropriate dosages and treatment regimens.

	Nicotine patch	Nicotine lozenge	Nicotine gum
Dosage (Registered drugs in Hong Kong)	7–25 mg	1mg	2mg or 4mg
Usage	Stick on dry, hairless skin	Keep in mouth and allow it to dissolve slowly; nicotine is absorbed through the oral mucosa	Chew slowly a few times to release nicotine, then park between cheek and gum. Repeat when taste fades
Duration of effect	16 hours or 24 hours per patch	About 20-30 minutes	About 30 minutes
Reference regimen	1 patch at a time Change daily Treatment duration: 8–12 weeks	1 piece at a time Maximum 20 pieces per day Treatment duration up to 12 weeks	1 piece at a time Maximum 24 pieces per day Treatment duration up to 12 weeks
Precautions	Rotate application site daily. Apply a new patch to the same skin site must be in at least 1-week interval.	Avoid eating or drinking 15 minutes before and during use Avoid chewing or swallowing Rotate to different areas of the mouth	Avoid eating or drinking 15 minutes before and during use Park in different areas of the mouth between cheek and gum
Possible adverse effects	Local skin reactions (redness, itching, burning), headache, insomnia	Nausea, hiccups, cough, heartburn, headache, flatulence, insomnia	Mouth/jaw soreness, hiccups, dyspepsia, hypersalivation Effects associated with incorrect use: dizziness, nausea/vomiting, throat and mouth irritation
Features	Regular usage pattern Less obvious when use, suitable for people who cannot eat/drink Long-lasting, stable blood nicotine levels	Oral substitute for tobacco Quickly relieves sudden cravings Flexible to use	Oral substitute for tobacco Quickly relieves sudden cravings Flexible to use
Not suitable for	People with skin conditions	People with sensitive stomach/intestines	People wearing dentures, braces, or dental bridges
Remarks	Light smokers (not smoking daily or smoking fewer than 5–10 cigarettes per day) can also use NRT to quit. Light smokers should consult smoking cessation counsellors to develop a more suitable plan. Pregnant and breastfeeding women should seek counselling to quit smoking first. NRT is generally safe for adolescents, but there is a lack of representative research data. Adolescents should seek counselling to quit smoking first. Persons who have any chronic illness, special medical condition, history of allergies, or are taking other medications, should consult a doctor, pharmacist, or other qualified healthcare professionals before using NRT. Carefully read the product instructions to fully understand usage and precautions.

Frequently asked questions about nicotine replacement therapy

Do I have to use NRT to quit smoking?

Many people can overcome withdrawal symptoms and quit smoking successfully by willpower alone (i.e. quitting cold turkey). However, experiencing withdrawal symptoms is not a sign of weak willpower, but rather the brain's response to nicotine addiction. To some people, NRT can reduce these discomforts and increase the chances of quitting successfully.
Will I get addicted using NRT?

There is currently no evidence suggesting smokers abuse NRT. The dose of nicotine provided by NRT is low and is released slowly, unlike the rapid “hit” from smoking, so it is less likely to trigger dependence. As long as NRT is used correctly according to the instructions, its dose can be gradually reduced over the course of treatment and eventually stopped completely.
Is the nicotine in NRT harmful?

Using NRT to quit smoking prevents smokers from inhaling additional carcinogens and harmful substances present in tobacco smoke and also increases the likelihood of successful quitting. According to World Health Organization (WHO), adverse effects of different forms of NRT are mostly mild, such as skin or oral discomfort. Cardiac adverse effects such as chest pains and palpitations were rare, and serious adverse effects were extremely rare. Overall, NRT is recognized by the WHO as a safe and effective smoking cessation medication and is widely used around the world.
Which forms of NTR are the most effective?

Any single form of NRT use yields comparable results, increasing quit rates by approximately 1.5 to 1.6 times. Using a combined forms of NRT is more effective for long‑term cessation than using a single form alone. The best results are achieved when cessation counselling is combined with pharmaceutical treatments.
Do I need to stop smoking completely while using NRT?

When using NRT, you must stop smoking completely. Keeping on smoking or reducing the number of cigarettes while using NRT adds extra nicotine. It would cause the total intake to become too high and increase the risk of side effects and health problems.
What should I do if I still crave for cigarettes while using NRT?

Persistent strong cravings may indicate insufficient dosage or incorrect use of NRT. Cravings can also be triggered by environmental or psychological factors. Quitters should consult smoking cessation counsellors and learn techniques to manage sudden craving. While NRT is a powerful aid to quitting, your mindset and behavioural changes are crucial.
Can e‑cigarettes help me quit smoking?

E-cigarettes are not a recognized tool for smoking cessation. WHO has repeatedly emphasized that e-cigarettes as consumer products have not been proven to be effective for cessation at the population level. Instead, e-cigarettes attract young users, and mounting evidence indicates their harms. In Hong Kong, the import, promotion, manufacture, sale, and possession for commercial purposes of alternative smoking products (including e-cigarettes) are already banned. Starting from 30 April 2026, possession of alternative smoking substances (including e-liquid) in public places will also be prohibited.

Combining counselling with NRT: A two-pronged approach against nicotine addiction

Correct use of NRT can reduce withdrawal symptoms and greatly improve the chances of quitting successfully. However, besides physical nicotine dependence, psychological factors (e.g., stress and boredom), smoking habits (e.g., smoking after waking up or after meals), and social environments (e.g., workplace routines or gatherings with friends) can also trigger cravings and lead to relapse. Encountering smoking cravings is a common barrier in the quit process. Smoking cessation counselling could help set up suitable NRT treatment and an effective quit plan to combat the difficulties and enhance the chance of cessation.

In Hong Kong, various smoking cessation service providers offer free NRT medication, counselling, and follow-up support for quitters. Through one-stop cessation services, quitters can better understand the correct use and side effects of cessation medications. They can also work with counsellors to review their smoking patterns, identify triggers, learn emotion-management techniques, and master practical skills to resist cravings. This approach helps quitters reduce cravings, strengthen determination, and achieve long-term cessation.

The Integrated Smoking Cessation Hotline 1833 183 is operated by the Department of Health. Anyone in need can call to receive quit-smoking information from registered nurses or make referral for free cessation programmes (including NRT medication, Chinese acupuncture, telephone counselling, etc.) offered by different organizations.

Learn more about smoking cessation services.

Related information:

This article and video are for general reference and health information purposes only and does not constitute medical advice or diagnosis. For any questions regarding your personal health or smoking cessation medications, please consult a qualified healthcare professional.

Media Centre