How Do Inhalants Produce Their Effects?

Many brain systems may be involved in the anesthetic, intoxicating, and reinforcing effects of different inhalants. Nearly all abused inhalants (other than nitrites) produce a pleasurable effect by depressing the CNS. Nitrites, in contrast, dilate and relax blood vessels rather than act as anesthetic agents.

Evidence from animal studies suggests that a number of commonly abused volatile solvents and anesthetic gases have neurobehavioral effects and mechanisms of action similar to those produced by CNS depressants, which include alcohol and medications such as sedatives and anesthetics.

A recent study indicates that toluene, a solvent found in many commonly abused inhalants—including model airplane glue, paint sprays, and paint and nail polish removers—activates the brain's dopamine system. The dopamine system has been shown to play a role in the rewarding effects of nearly all drugs of abuse.

How Can Inhalant Abuse Be Recognized?

Early identification and intervention are the best ways to stop inhalant abuse before it causes serious health consequences. Parents, educators, family physicians, and other health care practitioners should be alert to the following signs:

• Chemical odors on breath or clothing
• Paint or other stains on face, hands, or clothes
• Hidden empty spray paint or solvent containers, and chemical-soaked rags or clothing
• Drunk or disoriented appearance
• Slurred speech
• Nausea or loss of appetite
• Inattentiveness, lack of coordination, irritability, and depression

What Are the Short- and Long- Term Effects of Inhalant Use?

Although the chemical substances found in inhalants may produce various pharmacological effects, most inhalants produce a rapid high that resembles alcohol intoxication, with initial excitation then drowsiness, disinhibition, lightheadedness, and agitation. If sufficient amounts are inhaled, nearly all solvents and gases produce anesthesia—a loss of sensation—and even unconsciousness.

The chemicals found in solvents, aerosol sprays, and gases can produce a variety of additional effects during or shortly after use. These effects are related to inhalant intoxication and may include belligerence, apathy, impaired judgment, and impaired functioning in work or social situations; nausea and vomiting are other common side effects. Exposure to high doses can cause confusion and delirium. In addition, other possible effects include dizziness, drowsiness, slurred speech, lethargy, depressed reflexes, general muscle weakness, and stupor. For example, research shows that toluene can produce headache, euphoria, giddy feelings, and inability to coordinate movements.

Inhaled nitrites dilate blood vessels, increase heart rate, and produce a sensation of heat and excitement that can last for several minutes. Other effects can include flush, dizziness, and headache.

A strong need to continue using inhalants has been reported by many individuals, particularly those who have abused inhalants for prolonged periods over many days. Compulsive use and a mild withdrawal syndrome can occur with long-term inhalant abuse. A recent survey of 43,000 American adults suggests that inhalant users, on average, initiate use of cigarettes, alcohol, and almost all other drugs at younger ages and display a higher lifetime prevalence of substance use disorders, including abuse of prescription drugs, when compared with substance abusers without a history of inhalant use.