The logic of nicotine replacement is oddly simple: give the person the addictive chemical, just without the smoke and without the spike. It works. But the headline statistic everyone quotes about how well it works is almost always read wrongly, and that misreading is worth catching.
📚 What you need to know
Nicotine addiction is often treated with agonist substitution therapy, in the form of Nicotine Replacement Therapy (NRT).
NRT acts as an agonist on nicotinic receptors, stimulating dopamine release in a safer, controlled dose.
Available as gum, skin patches, sprays or pouches.
It is released into the bloodstream more slowly than from cigarettes and lacks the harmful chemicals in tobacco smoke.
The dose is reduced gradually over 2 to 3 months, managing withdrawal until the person can quit completely.
Naltrexone works the opposite way — it blocks the rewarding effects of nicotine, reducing the desire to smoke.
Stead et al. (2012) is your study, and its headline figure needs careful reading.
Agonist or antagonist?
This distinction is worth getting straight, because the two drugs on your syllabus sit on opposite sides of it.
The difference
An agonist activates the receptor • An antagonist blocks it
NRT is an agonist. It binds to nicotinic receptors and triggers dopamine release, mimicking nicotine’s effects at a safer, controlled dose. The craving is satisfied, just more gently.
Naltrexone is an antagonist. It blocks the rewarding effects of nicotine, so smoking stops being pleasurable and the desire to do it falls away.
So they attack the same problem from opposite ends: one supplies a safer version of the reward, the other removes the reward altogether. Some textbooks list naltrexone as “another NRT option”, but strictly it is not a replacement at all — it replaces nothing. Being able to say that cleanly shows real understanding.
Why delivery speed matters
The reason NRT works is not just what it delivers but how fast. A cigarette produces a sharp spike of nicotine within seconds, and that spike is what the brain learns to chase. A patch produces a slow, flat, boring supply that keeps withdrawal away without ever giving the hit.
The vertical axis is nicotine in the blood, with no numbers on purpose — what matters for the exam is the shape. The cigarette’s steep rise is the part the brain becomes addicted to, and no form of NRT reproduces it.
🔬 Stead et al. (2012)
A very large review of NRT trials
AIM
To compare the effectiveness of NRT against a placebo and other biological treatments for quitting smoking.
METHOD
A literature review of 150 drug trials, including over 50,000 participants, focusing on randomised trials and dose comparisons.
RESULTS
NRT in the form of gum, patches and sprays increased quit rates by 50 to 70% compared with placebo. Heavily addicted smokers responded best to higher doses of NRT gum. Higher doses of NRT patches did not significantly benefit heavily addicted smokers. Combination therapy — a patch plus a rapid delivery form such as gum — was more effective than using a single form of NRT.
CONCLUSION
NRT is an effective and viable treatment for quitting smoking.
Now read that headline number properly. “Increased quit rates by 50 to 70%” is a relative increase, not an absolute one. If the placebo quit rate were 10%, a 60% increase takes it to about 16% — not to 60%. Most students write as though NRT gets two thirds of smokers to quit. It does not. Spotting the difference between a relative and an absolute change is one of the most transferable skills in the whole course.
Why the dose findings make sense
Look at the two dose results together and a pattern appears. Higher-dose gum helped heavy smokers; higher-dose patches did not. That fits the delivery-speed graph exactly.
A patch supplies a steady background level. Raising that level does not help with a sudden craving, because the patch cannot respond to anything.
Gum is fast and taken on demand. A heavier smoker having more frequent, stronger cravings has something to answer them with.
Which is also why combination therapy wins. The patch and the gum are doing two different jobs: one prevents withdrawal, the other handles the moments. That is the explanation examiners want, not just the observation.
Evaluating drug therapy for addiction
Strengths
Drug treatment is accessible, and cheaper and easier to engage with than CBT, requiring only a prescription and medical supervision.
It frames addiction as a medical condition rather than a moral weakness, which reduces stigma and encourages more people to seek help.
The evidence base is very large: 150 trials and over 50,000 participants.
Gradual dose reduction manages withdrawal rather than demanding sudden abstinence.
Limitations
Side effects such as sleep disturbances, digestive issues or headaches may cause non-compliance and relapse.
Effectiveness is not universal. Small genetic variations between people significantly affect outcomes.
For example, naltrexone’s effectiveness depends on variations in the mu-opioid receptor gene.
The 50 to 70% figure is a relative increase and is easily overstated.
Linking to the concepts
Perspective: although NRT clearly plays a role in reducing nicotine addiction, it cannot work in isolation. The smoker has to want to quit before NRT is even started. Motivation and, to some extent, self-efficacy are key factors in any decision to improve one’s health.
Change: research on NRT should include follow-up studies assessing the longevity of the effect. NRTs may only work in the short term, so it is in the interest of public health to investigate how well their effects hold up over time.
The reductionism point, previewed. Notice that the perspective concept above is already pointing at the next page. A drug can change receptor activity, but it cannot supply motivation, and motivation is where quitting actually starts. That gap is exactly what the reductionism debate is about.
EXAM ANSWER
Discuss one biological treatment for one health problem. [22 marks]
Mechanism, using the right word
NRT is agonist substitution: it activates nicotinic receptors and triggers dopamine release at a controlled dose, without tobacco smoke.
Add the detail that shows understanding
Delivery is slower than a cigarette, and the dose is tapered over 2 to 3 months to manage withdrawal.
Evidence
Stead et al.: 150 trials, 50,000+ participants; combination therapy outperformed single-form NRT.
Evaluate the statistic itself
The 50 to 70% improvement is relative to placebo, so absolute quit rates remain modest.
Then the human limitation
NRT cannot supply motivation, and genetic variation means it does not work equally for everyone.
Conclude: effective support for quitting, not a treatment on its ownquestioning how a statistic is expressed is a genuinely high-level evaluation move
💡 Exam tips
Use the word agonist and define it. It is precise and directly creditworthy.
List the delivery forms — gum, patches, sprays, pouches. Quick, specific marks.
Explain why combination therapy works. The observation alone is not enough.
The relative-versus-absolute point is your best single evaluation sentence on this page.
The stigma argument is a genuine strength of the medical model. Most candidates only criticise it.
Cross-link to the CBT for nicotine page, since the same combination logic appears there.
⚠ Common mix-ups
Reading “50 to 70%” as the quit rate. It is the increase relative to placebo.
Calling naltrexone a replacement therapy. It blocks the reward instead of replacing it.
Saying NRT has no nicotine. It has nicotine. What it lacks are the other harmful chemicals in smoke.
Claiming higher doses always work better. That held for gum, not for patches.
Calling Stead an experiment. It is a literature review of randomised trials.
Forgetting the tapering. Gradual reduction over 2 to 3 months is part of the treatment, not an afterthought.
Up next: Is Drug Treatment Too Reductionist? — both drug pages have ended on the same complaint. Time to make that complaint properly, and to be fair to reductionism while doing it.
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