Central nervous system (CNS) stimulants are substances that boost the activity of the central nervous system.

CNS stimulants can help treat conditions such as attention deficit hyperactivity disorder (ADHD), depression, and narcolepsy, which causes excessive sleepiness.

However, people may also use them to improve exercise performance and for recreational purposes. The Food and Drug Administration (FDA) does not approve the drugs for these uses.

Examples of CNS stimulants include amphetamines, methylphenidate, caffeine, and cocaine.

This article looks at some common types of CNS stimulants, when a doctor might prescribe them, and possible adverse effects.

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CNS stimulants are drugs that increase alertness, attention, physical activity, and energy levels. They do this by boosting the levels of certain brain chemicals.

CNS stimulants work differently, depending on the individual drug. Most either block or increase the levels of certain neurotransmitters.

For instance, amphetamines raise levels of norepinephrine and dopamine in the body, while caffeine disrupts the way the body uses adenosine. Adenosine causes drowsiness. By reducing adenosine activity, caffeine increases energy levels.

Doctors prescribe CNS stimulants to treat a range of conditions, such as:

However, people also use CNS stimulants for other purposes:

  • Caffeine can help people stay awake.
  • Cocaine, MDMA, ecstasy, and khat are recreational drugs that people may take for their euphoric and other effects.
  • Amphetamines may help enhance athletic performance.

Learn more about the long- and short-term effects of the ADHD medication Ritalin.

Here are some of the CNS stimulants doctors prescribe:

Generic nameBrand nameUses
armodafinilNuvigilnarcolepsy, shift sleep disorders, obstructive sleep apnea (OSA)
modafinilProvigilsleep disorders
solriamfetolSunosinarcolepsy and OSA
pitolisantWakixsleepiness and cataplexy, which involves bouts of muscle weakness
methylphenidateRitalin, ConcertaADHD
dextroamphetamine and amphetamineAdderallADHD
serdexmethylphenidate and dexmethylphenidateAzstarysADHD
methamphetamineDesoxynsometimes prescribed for ADHD
pseudoephedrineAfrinola decongestant present in various over-the-counter medications

Other CNS stimulants include:

These are not generally suitable as treatment options for any health condition. Used recreationally, they are not monitored, and their use can lead to severe adverse effects, dependence, and death.

It is important to note that they are not FDA-approved substances.

CNS stimulants can have adverse effects. A number of these drugs carry a boxed warning due to the risk of overdose, dependence, and other unwanted effects.

The adverse effects of CNS stimulants will depend on various factors, including which substance it is, how the person uses it, and other health conditions they may have.

In general, the use of CNS stimulants may lead to:

More severe adverse effects include:

Anyone who experiences severe adverse effects needs urgent medical attention, as they can quickly become fatal.

When a doctor prescribes a medication containing a CNS stimulant, they will likely recommend regular monitoring to manage or help prevent possible adverse effects.

A doctor may not prescribe CNS stimulants to the following people due to the increased risk of adverse effects:

  • those with a history of cardiac problems, including high blood pressure
  • people with untreated hyperthyroidism or glaucoma
  • children under 12 years of age — although Ritalin, for instance, is suitable for children as young as 6 years
  • those who are pregnant
  • people with a history of adverse effects or susceptibility to CNS stimulants

Learn more about the side effects of Provigil.

Here are some questions people often ask about CNS stimulants.

What are some examples of CNS stimulants?

CNS stimulants include a wide variety of substances, ranging from methylphenidate (Ritalin), which is an ADHD drug, to caffeine and cocaine.

What is the most frequent use of CNS stimulants?

Caffeine is the most widely used CNS stimulant. However, doctors commonly prescribe drugs containing other CNS stimulants to treat conditions such as ADHD and narcolepsy.

How do CNS stimulants help people with ADHD?

CNS stimulants can help alleviate the manifestations of ADHD, such as hyperactivity, inattentiveness, poor concentration, and impulsiveness. They can help enhance alertness, comprehension, response inhibition, and immediate memory.

Learn more about ADHD

Find out more about ADHD, symptoms, treatment options, and more from our dedicated hub.

CNS stimulants are substances that increase the activity of the CNS by either boosting the levels of certain brain chemicals or blocking the activity of others.

They range from caffeine to treatments for various medical conditions, such as ADHD. They also include the recreational drugs cocaine and ecstasy.

Anyone whose prescription contains a CNS stimulant should follow a doctor’s instructions with care, as adverse effects can sometimes arise.