The lungs absorb inhaled chemicals into the bloodstream very quickly, sending them throughout the brain and body. Within minutes of inhalation, users feel "high." The effects are similar to those produced by alcohol and may include slurred speech, lack of coordination, euphoria, and dizziness. The high usually lasts only a few minutes.
With repeated inhalations, many users feel less inhibited and less in control. Some may feel drowsy for several hours and experience a lingering headache.
Effects on the Brain
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.
One of these fatty tissues is myelin, a protective cover that surrounds many of the body's nerve fibers. Myelin helps nerve fibers carry their messages to and from the brain. Damage to myelin can slow down communication between nerve fibers.
Long-term inhalant use can break down myelin. When this happens, nerve cells are not able to transmit messages as efficiently, which can cause muscle spasms and tremors or even permanent difficulty with basic actions like walking, bending, and talking. These effects are similar to what happens to patients with multiple sclerosis—a disease that also affects myelin.
Inhalants also can damage brain cells by preventing them from receiving 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 abuses inhalants may lose the ability 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 clumsily.
Other Health Effects
Regular abuse of inhalants can cause serious harm to vital organs besides the brain. Inhalants can cause heart damage, liver failure, and muscle weakness. Certain inhalants can also cause the body to produce fewer blood cells, which can lead to a condition known as aplastic anemia (in which the bone marrow is unable to produce blood cells). Frequent long-term use of certain inhalants can cause a permanent change or malfunction of peripheral nerves, called polyneuropathy.
Specific Effects by Type of Inhalant
Depending on the type of inhalant abused, the harmful health effects will differ. The table below lists a few examples.