How does chronic inhalant abuse affect the brain?

Answer: Inhalant abuse has several consequences for the brain, ranging from poor coordination, slowed reflexes, dizziness, and even cell degeneration.

inhalant abuse brain

Many drugs of abuse enter into the body via inhalation, particularly after the volatilization of certain compounds or preparations of the drug. For example, the burning of preserved tobacco allows nicotine, the primary psychoactive compound of cigarettes, can be turned into a smoke at high temperatures and subsequently inhaled. This process can be done for many drugs of abuse, including marijuana, crack cocaine, or methamphetamine, for example.

However, the class of drugs referred to as “inhalants” generally refers to substances that are almost always taken into the body via inhalation with no other known route of administration. Some of the more well known drugs of this class include volatile anesthetics, solvents such as paint thinner, or adhesives.

Drug effects

It is unclear as to how inhalant drugs affect the nervous system on a cellular level. Gases taken in through inhalation dissolve very readily in the blood, since the exchange of oxygen with carbon dioxide occurs in the lungs rapidly. However, once in the blood, it is difficult to know where these drugs end up. Gases can pass through cell membranes passively, so it is almost impossible to predict the distribution of gaseous compounds.

Most inhalant substances that are abused produce a depression of the central nervous system. An abuser may experience an early excitation before a depression of activity, leading to sluggishness, impaired judgement, or agitation. Weakened reflexes is common.

Inhalant nitrite compounds, sometimes colloquially called “poppers,” often produce the opposite effect. These substances act to relax smooth muscles, which can surround blood vessels. In doing so, they dilate blood vessels, which can result in increased CNS activity. This can produce the feeling of warmth or a sudden rush of excitement.

The most common cause of death from inhalant abuse is hypoxia-related suffocation. A person who is breathing the inhalant substances fails to get sufficient oxygen into their brain cells. The lightheadedness that someone might first experience during inhalant abuse may be in part due to the hypoxic conditions in the brain.


Inhalants are a frequently abused drug, particularly among the young. It was estimated that among high school students, about 20% have tried inhalants. One reason that inhalants are more popular among this age demographic is the ease of access. Many of these substances are not tightly regulated, and can be easily purchased from a store. For example, inhaling the compressed air in a tube of Cool Whip can produce a rapid onset of euphoria. Similar chemicals can be found in cans of compressed air.

As with most other drugs of abuse, there is a range of users. Many discontinue their use of the drug as they get older, some continue to use inhalants recreationally, and others are considered to have a serious substance use disorder as characterized by the traits in the Diagnostic and Statistical Manual for Psychiatric Diseases (DSM-V).

Chronic severe use of this class of drugs is often part of a polydrug abuse pattern, where a person may use several different types of drugs on each session of drug use. Additionally, among patients who abuse inhalants, they are more likely to initiate use of tobacco, alcohol, or other drugs at an earlier age, and have an elevated long-term risk of drug abuse.