Nicotine and caffeine are central nervous system (CNS) stimulants. Both these substances act on the brain, causing a number of effects.

Nicotine is a substance that is present in tobacco plants. It is a highly addictive substance that may create a temporary feeling of well-being and relaxation.

Caffeine is a stimulant that occurs naturally in some foods. It most commonly comes from coffee beans. Caffeine may make a person experience increased energy levels and feel more alert.

This article looks at the effects of nicotine and caffeine and discusses potential interactions. It also outlines the effects of nicotine and caffeine withdrawal and when to speak with a healthcare professional.

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Nicotine and caffeine affect a person’s brain in different ways.


When a person consumes nicotine, it acts on specific nicotinic acetylcholine receptors in the brain. This causes the brain to release a neurotransmitter, or chemical messenger, called acetylcholine, which plays a role in various bodily processes.

Nicotine also stimulates the dopaminergic system in the brain, which releases another neurotransmitter called dopamine.

When nicotine interacts with the brain in this way, it can cause a person to experience a slight, brief feeling of euphoria due to the release of endorphins. These chemicals may help:

  • reduce stress
  • relieve pain
  • improve mood and feelings of well-being

Because nicotine increases the amount of dopamine in a person’s reward circuits, it can reinforce the behavior of consuming nicotine, for example, through smoking.

If a person repeatedly exposes themselves to nicotine, it can alter these reward circuits’ sensitivity to dopamine. This can lead to changes in other brain circuits involved in:

  • learning
  • stress
  • self-control

These changes can cause many people who use tobacco to develop nicotine dependence.

Learn more about the CNS.


Caffeine is also a CNS stimulant. It works by inhibiting the release of a chemical called adenosine in the brain, which increases the activity of the dopaminergic system.

Adenosine slows down cell activity and promotes sleep. When a person is awake, the levels of extracellular adenosine buildup, and when they are asleep, their adenosine levels go down.

Caffeine binds to the same receptors on cells as adenosine. As a result, the cells are unable to sense adenosine. This means that the cellular activity speeds up instead of slowing down. So, when a person consumes caffeine, they may experience a feeling of alertness and increased energy.

If a person regularly drinks beverages or eats foods that contain caffeine, they may develop a physical and psychological dependence on it.

Learn more about caffeine sensitivity here.

Nicotine and caffeine can increase a person’s heart rate and produce stimulation and arousal. They may also improve a person’s attention.

Combining these two substances may enhance these effects.

Nicotine and caffeine also affect the release of dopamine. Studies suggest that when these substances interact, they may combine to have a more significant effect on the following:

  • pain perception
  • voluntary movement functions
  • behavioral traits

Learn about dopamine deficiency.

If a person becomes dependent on nicotine or caffeine, they may experience withdrawal symptoms if they stop taking the substance.

Nicotine withdrawal

Symptoms of nicotine withdrawal include:

Learn more about nicotine withdrawal symptoms and how to cope.

Caffeine withdrawal

Symptoms of caffeine withdrawal include:

  • headache
  • fatigue
  • decreased alertness
  • drowsiness
  • difficulty concentrating
  • irritability
  • decreased energy levels
  • decreased contentedness
  • depressed mood
  • feeling foggy and not clear-headed

Learn more about the symptoms of caffeine withdrawal.

Anyone living with nicotine addiction who wants to quit smoking might consider talking with a doctor who may be able to offer some helpful advice to make quitting smoking easier.

A healthcare professional may also be able to suggest possible medications a person can use to help them quit. Doctors may also put a person in contact with local support groups and resources to help them quit smoking.

Similarly, a doctor might also advise on steps a person can take to help reduce the amount of caffeine they consume.

Learn more about addiction.

Caffeine and nicotine are both CNS stimulants. They act on the brain in similar ways, producing similar and different results.

Caffeine and nicotine both increase a person’s heart rate and produce stimulation and arousal. The substances can interact with each other and potentially enhance these effects.

Nicotine is also highly addictive, and a person can experience withdrawal symptoms if they suddenly stop consuming it. Some symptoms of nicotine withdrawal include urges or cravings to smoke, feeling irritated, gaining weight, and having trouble sleeping.

A person can also develop a physical and psychological dependence on caffeine. Some symptoms of caffeine withdrawal include fatigue, headaches, depressed mood, and decreased energy levels.

People might want to speak with a healthcare professional about reducing their nicotine and caffeine intake.