Inhalants: Physiological effects
Last modified: Sunday, 31. May 2009 - 4:35 pm
The physical effects of inhalants vary because different inhalants combine different chemicals, and they produce different effects during and shortly after use.
Based on their studies of animals, scientists believe that, in general, when toxic vapors circulate to the brain, they depress the central nervous system. The action is similar to that of alcohol, sedatives, and anesthetics. Thus, many of the immediate physical changes inhalant users experience are similar to those caused by alcohol or anesthetics, including relaxation, slurred speech, slowed reflexes, lack of coordination, sleepiness, dizziness, headache, nausea, and vomiting. Abusers might also sneeze, cough, and drool.
Overdose can lead to a fast, irregular heartbeat, which can be fatal — a syndrome called sudden sniffing death.
Toluene, an ingredient in many abused inhalants, possibly works on dopamine, a brain chemical involved in the pleasure-producing effects of other abused substances. More research is needed to understand how inhalants produce their Physiological effects.
Nitrites, used to enhance sexual experiences, are in a different category in terms of their effects. When inhaled, nitrates dilate the blood vessels and speed the heartbeat. As a result, abusers feel warm and excited for several minutes. They may also become flushed and dizzy, and may develop a headache.
Harmful side effects
The toxic chemicals in inhalants are capable of damaging many different organs and body systems, including the nervous system (brain, spinal cord, and nerves), heart, lungs, circulatory system, liver, kidneys, and the senses of smell, sight, and hearing. The young age of most abusers increases the potential for damage, because their bodies have not fully matured.
Trichloroethylene, an ingredient in spray paints and correction fluid, can damage the liver. Nitrites and methylene chloride (in paint thinner) reduce the blood’s ability to carry proper amounts of oxygen. Inhaled spray paint can damage the lungs. Regular users of nitrous oxide and hexane (an ingredient in some glues and fuels) damage their nervous systems, resulting in numbness, tingling, or paralysis. Toluene hinders the kidneys’ ability to regulate the amount of acid in the blood. (When the abuse stops, the kidneys go back to properly controlling acid levels, but the user may later develop kidney stones.) Trichloroethylene, a chemical in spot removers and degreasers, can damage hearing, vision, and the liver. Toluene affects reproduction, and may cause changes in chromosomes, abnormalities during pregnancy, and premature births. An overdose of amyl nitrite can be fatal.
Other side effects of inhalant use include persistent headaches, appetite loss, nosebleeds (sometimes severe enough to require hospitalization), and skin rashes (from contact with glue). Long-term inhalant abusers may lose weight, muscle tone and strength, and coordination.
Inhalants cross the placenta and are dangerous to the developing fetus. Infants born to solvent abusers suffer neonatal (newborn) inhalant withdrawal: high-pitched, extreme crying; poor sleeping and eating; quivering and trembling; and rigid, tense muscles. Researchers do not know if abnormalities that these infants develop are due to inhalants or another cause, such as alcohol. Studies of animals indicate that toluene causes low birth weight, skeletal abnormalities, and development delays.
Long-term health effects
Long-term, heavy use of inhalants damages the brain and the network of nerves that connects the brain and spinal cord to other organs. Research already conducted is inadequate, however, to determine the level of damage caused by relatively low levels of inhalant use. There also is insufficient information on the extent to which damage is reversible once a person stops using the substances.
Most damage to the nervous system develops after the abuse has continued two or three times a week for at least six months; but any amount of solvent abuse can break down nerve fibers.
Because different inhalants damage different parts of the brain and nervous system, the resulting problems depend on which areas were affected. If the frontal cortex is affected, problem-solving and advance-planning skills are impaired. The abuser may lose physical coordination and speed if the cerebellum is damaged. Oxygen deprivation in the hippocampus causes problems with learning new information or remembering familiar things. Damage to the myelin sheath (a protective coating on nerve cells) disrupts the nerves’ ability to send and receive the messages that enable the body to think and act.
Health effects from inhalants range from mild to severe. A distinction between harmful side effects and long-term effects has not been fully determined. “Although some inhalant-induced damage to the nervous and other organ systems may be at least partially reversible when inhalant abuse is stopped, many syndromes caused by repeated or prolonged abuse are irreversible,” according to the NIDA research report on inhalants, which was updated in February 2002.
NIDA’s list of irreversible effects include hearing loss, limb spasms, brain damage, and bone marrow damage. Serious but potentially reversible effects include liver and kidney damage, and depletion of oxygen from the blood.
Nitrites carry special risks, even with modest use. Based on their research with animals, scientists suspect that nitrite abuse reduces the number of cells in the immune system. This possibly hinders the body’s efforts to fight infectious diseases and resist the growth of tumors.
Death is also a possible consequence of inhalant abuse, because the chemicals displace oxygen, leading to an increased risk of sudden sniffing death. Users also die from asphyxiation (from inhaling repeatedly, which leaves the lungs full of chemicals instead of oxygen), suffocation (from blocking air to the lungs while inhaling fumes from a plastic bag over the head), choking (from inhaling and choking on vomit), and from a variety of accidental injuries caused by mental and physical effects of inhalants (car wrecks, drowning, falls, burns).