NIDA for Teens: The Science Behind Drug Abuse
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Inhalants

How Do Inhalants Affect the Brain?

The lungs absorb inhaled chemicals into the bloodstream very quickly, sending them throughout the brain and body. Nearly all inhalants (except nitrites) produce a pleasurable effect by slowing down brain activity. Nitrites, in contrast, expand and relax blood vessels.

Short-Term Effects

Within seconds, users feel intoxicated and experience effects similar to those of alcohol, such as slurred speech, lack of coordination, euphoria (a feeling of intense happiness), and dizziness. Some users also experience lightheadedness, hallucinations (seeing things that are not really there), and delusions (believing something that is not true). If enough of the chemical is inhaled, nearly all solvents and gases produce anesthesia—a loss of sensation—and can lead to unconsciousness.

The high usually lasts only a few minutes, causing people to continue the high by inhaling repeatedly, which is very dangerous. Repeated use in one session can cause a person to lose consciousness and possibly even die.

With repeated inhaling, many users feel less inhibited and less in control. Some may feel drowsy for several hours and have a headache that lasts a while.

Long-Term Effects

Inhalants often contain more than one chemical. Some chemicals leave the body quickly, but others stay for a long time and get absorbed by fatty tissues in the brain and central nervous system. Over the long term, the chemicals can cause serious problems:

  • Damage to nerve fibers. Long-term inhalant use can break down the protective sheath around certain nerve fibers in the brain and elsewhere in the body. When this happens, nerve cells are not able to send messages as well, which can cause muscle spasms and tremors or even permanent trouble with basic actions like walking, bending, and talking. These effects are similar to what happens to people with multiple sclerosis.
  • Damage to brain cells. Inhalants also can damage brain cells by preventing them from getting enough oxygen. The effects of this condition, also known as brain hypoxia, depend on the area of the brain affected. The hippocampus, for example, is responsible for memory, so someone who repeatedly uses inhalants may be unable to learn new things or may have a hard time carrying on simple conversations. If the cerebral cortex is affected, the ability to solve complex problems and plan ahead will be compromised. And, if the cerebellum is affected, it can cause a person to move slowly or be clumsy.

Learn more about how the brain works and what happens when a person uses drugs.