A nicotine patch is a small, flat device that delivers nicotine through the skin instead of through the lungs or the mouth. You press it onto a clean patch of skin, leave it there for the day, and the nicotine it holds moves slowly into the body. That is the whole idea. The details of how it happens explain most of what people notice about patches: why nothing seems to happen for a while, why the effect is even rather than sharp, and why the label tells you to move it to a new spot each day.
This guide walks through it in order: what a patch is made of, how nicotine gets through the skin, what the timing looks like, and what changes from one patch to the next.
Patches have been around since 1979
Skin patches are not new. The first transdermal patch for delivering a drug through the skin was approved in the United States in 1979: a three-day patch for motion sickness. Since then the format has been used for pain relief, hormones and more, and nicotine patches are among the products sold over the counter in many countries.
That history matters because the basic engineering is well understood. A nicotine patch uses the same principles as any other skin patch. What changes from brand to brand is the amount of nicotine, how the patch controls its release, and what else is on the ingredient list.
What a patch is made of
Every nicotine patch is built in layers. On the outside is the backing, a thin flexible film that keeps the contents in and protects them from clothing, water and air. Underneath is the layer that holds the nicotine. In some designs that layer is a reservoir; in many modern patches the nicotine is spread through a polymer matrix or directly through the adhesive itself.
Some patches add a membrane between the nicotine layer and the skin. Its job is to limit how fast the nicotine can leave the patch. Then there is the adhesive that holds the patch flat against the skin, and finally the release liner: the piece you peel off and throw away just before you put the patch on.
A review of nicotine kinetics by Benowitz and colleagues describes it plainly: every nicotine patch on the US market is a multilayer patch, and the rate at which nicotine is released into the skin is set by the permeability of the skin, the rate of diffusion through the polymer matrix, the rate of passage through a membrane, or a mix of these.
How nicotine gets through the skin
Skin is a barrier, and its outermost layer, the stratum corneum, is the main thing a patch has to get past. Most substances can't cross it in useful amounts, which is why only some drugs are sold as patches. Nicotine is one of the ones that can. In its base form it passes through skin readily. The same review notes that this is why tobacco harvesters handling wet leaves can absorb enough nicotine to feel sick from it.
A patch takes advantage of that by holding nicotine at a high concentration right against the skin. Molecules move from where there are more of them to where there are fewer, so nicotine drifts out of the patch, through the skin layers and into the small blood vessels below. From there it travels around the body like nicotine from any other source.
There is no pump and no trigger. The patch works by diffusion alone, which is why wearing it correctly matters: full contact with clean, dry skin gives the nicotine a consistent path.
Why nothing seems to happen at first
People sometimes notice that a patch doesn't seem to do anything for the first while. That is expected. The skin has to load up before nicotine reaches the bloodstream in measurable amounts. Benowitz and colleagues report an initial lag of about an hour before nicotine appears in the blood, for every patch they looked at.
After that, levels rise slowly. In the studies the review summarises, blood nicotine from a patch took hours to reach its highest point: roughly three to twelve hours depending on the brand and strength. For comparison, nicotine from a cigarette reaches its peak in venous blood within about five to eight minutes. A patch is the slowest common way of taking nicotine, by a wide margin.
A steady level instead of peaks
Because a patch keeps releasing nicotine for as long as it is worn, it tends to produce a fairly even level through the day rather than a series of short spikes. The body breaks nicotine down at a steady pace (its half-life averages about two hours), so a source that keeps topping it up slowly holds the level relatively flat.
That flat profile is the defining feature of the format. It is also why a patch feels very different from faster forms of nicotine, which deliver a quick rise and then fall away.
What happens when you take it off
Taking the patch off doesn't stop absorption straight away. Some nicotine has already moved into the skin under the patch, and it keeps reaching the bloodstream for a while afterwards. The review puts that at about 10% of the total dose, absorbed after the patch is removed.
That skin store is one reason patch labels say to use a different spot each day. It also explains why your skin under the patch can look a little red when you peel it off: it has been covered and in contact with adhesive and nicotine all day. Moving the patch around gives each spot time to recover.
Why strengths and wear times differ
Pharmacy patches are sold in several strengths, commonly 21, 14 and 7 mg, and are labelled for either 16 or 24 hours of wear. The figures in the review show that the label dose isn't the whole story: two patches with the same milligram figure from different makers produced different blood levels and reached their peak at different times. Rates of delivery vary between patch designs.
So when you compare patches, the milligram figure tells you how much nicotine a patch holds, and the wear time tells you the period it is designed for. Neither tells you everything, but both should be on the label. Ours holds 7 mg per patch and is worn one patch a day.
What affects how a patch delivers
A few things on your side change how evenly a patch works. Skin that is oily, damp or covered in lotion can stop the adhesive from sealing, and an edge that lifts gives the nicotine a less consistent path. Hairy skin has the same effect. That is why the usual advice is a clean, dry, mostly hair-free spot on the upper arm, chest, back or hip.
Heat matters too. Warming the skin is one of the methods researchers use to push more of a drug through it, so keep heat pads and hot water bottles off a patch. And a patch that has been cut, folded or left out of its sachet won't behave as designed.
Where the other ingredients fit
Our patch lists four ingredients: natural tobacco extract, which supplies the 7 mg of nicotine, plus resveratrol, liquorice root and clove. The botanicals sit in the patch alongside the nicotine and are named on the label so you know exactly what you are putting on your skin.
The research on each of those plant compounds is separate from the research on how patches work, and none of it is a study of this patch. The home page links to the published reviews if you want to read them.
The short version
A nicotine patch is a layered film that holds nicotine against the skin. Nicotine diffuses through the skin into the blood, starting after about an hour and building over several hours, which gives a slow and fairly even level rather than peaks. Some keeps coming through after the patch is off. Strength, wear time and patch design all change the details, which is why reading the label properly is worth the minute it takes.
Nicotine is an active substance in any form. Keep patches away from children and pets, and talk to a doctor before using one if you are pregnant, breastfeeding or have a heart condition or other medical condition.
