Inhalants and related disorders
The inhalants are a class of drugs that include a broad range of chemicals found in hundreds of different products, many of which are readily available to the general population. These chemicals include volatile solvents (liquids that vaporize at room temperature) and aerosols (sprays that contain solvents and propellants). Examples include glue, gasoline, paint thinner, hair spray, lighter fluid, spray paint, nail polish remover, correction fluid, rubber cement, felt-tip marker fluids, vegetable sprays, and certain cleaners. The inhalants share a common route of administration— that is, they are all drawn into the body by breathing. They are usually taken either by breathing in the vapors directly from a container (known as "sniffing"); by inhaling fumes from substances placed in a bag (known as "bagging"); or by inhaling the substance from a cloth soaked in it (known as "huffing"). Inhalants take effect very quickly because they get into the bloodstream rapidly via the lungs. The "high" from inhalants is usually brief, so that users often take inhalants repeatedly over several hours. This pattern of use can be dangerous, leading to unconsciousness or even death.
The latest revision of the manual that is used by mental health professionals to diagnose mental disorders is the Diagnostic and Statistical Manual of Mental Disorders published in 2000 (also known as DSM-IVTR ). It lists inhalant dependence and inhalant abuse as substance use disorders. In addition, the inhalantinduced disorder of inhalant intoxication is listed in the substance-related disorders section as well. Inhalant withdrawal is not listed in the DSM-IV-TR because it is not clear that there is a "clinically significant" withdrawal syndrome. In addition, withdrawal is not included as a symptom of inhalant dependence, whereas withdrawal is a symptom of dependence for all other substances. Withdrawal symptoms are symptoms that occur when a person who is dependent on a substance stops using the substance.
Anesthetic gases (such as nitrous oxide, chloroform, or ether) and nitrites (including amyl or butyl nitrite) are not included under inhalant-related disorders in the DSM-IV-TR because they have slightly different intoxication syndromes. Problems with the use of these substances are to be diagnosed under "Other Substance-Related Disorders." There is, however, a significant degree of overlap between the symptoms of disorders related to inhalants and these "other" substances.
Inhalant dependence, or addiction , is essentially a syndrome in which a person continues to use inhalants in spite of significant problems caused by or made worse by the use of these substances. People who use inhalants heavily may develop tolerance to the drug, which indicates that they are physically dependent on it. Tolerance is the reduced response to a drug that develops with repeated use.
Inhalant abuse is a less serious condition than inhalant dependence; in most cases, it does not involve physical dependence on the drug. Inhalant abuse refers essentially to significant negative consequences from the recurrent use of inhalants.
When a person uses enough of an inhalant, they will get "high" from it. The symptoms of intoxication differ slightly depending on the type of inhalant, the amount used, and other factors. There is, however, a predictable set of symptoms of inhalant intoxication. When too much of the substance is taken, an individual can overdose.
Dependence on inhalants involves problems related to the use of inhalants. It is often difficult for a person to stop using the inhalants despite these problems. Individuals dependent on inhalants may use these chemicals several times per week or every day. They may have problems with unemployment, with family relationships, and/or such physical problems as kidney or liver damage caused by the use of inhalants.
People who abuse inhalants typically use them less frequently than those who are dependent on them. Despite less frequent use, however, a person with inhalant abuse suffers negative consequences. For example, the use of inhalants may contribute to poor grades or school truancy.
Intoxication from inhalants occurs rapidly (usually within five minutes) and lasts for a short period of time (from five to 30 minutes). Inhalants typically have a depressant effect on the central nervous system, similar to the effects of alcohol; and produce feelings of euphoria (feeling good), excitement, dizziness, and slurred speech. In addition, persons intoxicated by inhalants may feel as if they are floating, or feel a sense of increased power. Severe intoxication from inhalants can cause coma or even death.
Causes and symptoms
Because inhalants are readily available and inexpensive, they are often used by children (ages six to 16) and the poor. Factors that are associated with inhalant use include poverty; a history of childhood abuse; poor grades; and dropping out of school. The latter two factors may simply be a result of inhalant use, however, rather than its cause.
The use of inhalants is highly likely to be influenced by peers. Inhalants are often used in group settings. The solitary consumption of inhalants is associated with heavy, prolonged use; it may indicate that the person has a more serious problem with these substances.
INHALANT DEPENDENCE. The DSM-IV-TR specifies that three or more of the following symptoms must occur at any time during a 12-month period (and cause significant impairment or distress) in order to meet diagnostic criteria for inhalant dependence:
- Tolerance. The individual either has to use increasingly higher amounts of the drug over time in order to achieve the same effect, or finds that the same amount of the drug has much less of an effect over time than before. After using inhalants regularly for a while, people may find that they need to use at least 50% more than the amount they started with in order to get the same effect.
- Loss of control. The person either repeatedly uses a larger quantity of inhalant than planned, or uses the inhalant over a longer period of time than planned. For instance, someone may begin using inhalants on school days, after initially limiting their use to weekends.
- Inability to stop using. The person has either unsuccessfully attempted to cut down or stop using the inhalants, or has a persistent desire to stop using. Users may find that despite efforts to stop using inhalants on school days, they cannot stop.
- Time. The affected person spends large amounts of time obtaining inhalants, using them, being under the influence of inhalants, and recovering from their effects. Obtaining the inhalants might not take up much time because they are readily available for little money, but the person may use them repeatedly for hours each day.
- Interference with activities. The affected person either gives up or reduces the amount of time involved in recreational activities, social activities, and/or occupational activities because of the use of inhalants. The person may use inhalants instead of playing sports, spending time with friends, or going to work.
- Harm to self. The person continues to use inhalants in spite of developing either a physical (liver damage or heart problems, for example) or psychological problem (such as depression or memory problems) that is caused by or made worse by the use of inhalants.
INHALANT ABUSE. The DSM-IV-TR specifies that one or more of the following symptoms must occur at any time during a 12-month period (and cause significant impairment or distress) in order to meet diagnostic criteria for inhalant abuse:
- Interference with role fulfillment. The person's use of inhalants frequently interferes with his or her ability to fulfill obligations at work, home, or school. People may find they are unable to do chores or pay attention in school because they are under the influence of inhalants.
- Danger to self. The person repeatedly uses inhalants in situations in which their influence may be physically hazardous (while driving a car, for example).
- Legal problems. The person has recurrent legal problems related to using inhalants (such as arrests for assaults while under the influence of inhalants).
- Social problems. The person continues to use inhalants despite repeated interpersonal or relationship problems caused by or made worse by the use of inhalants. For example, the affected person may get into arguments related to inhalant use.
INHALANT INTOXICATION. The DSM-IV-TR specifies that the following symptoms must be present in order to meet diagnostic criteria for inhalant intoxication:
- Use. The person recently intentionally used an inhalant.
- Personality changes. The person experiences significant behavioral or psychological changes during or shortly after use of an inhalant. These changes may include spoiling for a fight; assaultiveness; poor judgment; apathy ("don't care" attitude); or impaired functioning socially or at work or school.
- Inhalant-specific intoxication syndrome. Two or more of the following symptoms occur during or shortly after inhalant use or exposure: dizziness; involuntary side-to-side eye movements (nystagmus); loss of coordination; slurred speech; unsteady gait (difficulty walking); lethargy ( fatigue ); slowed reflexes; psychomotor retardation (moving slowly); tremor (shaking); generalized muscle weakness; blurred vision or double vision; stupor or coma; and euphoria (a giddy sensation of happiness or well-being).
Inhalants are one of the few substances more commonly used by younger children rather than older ones. It has been estimated that 10%–20% of youths aged 12–17 have tried inhalants. About 6% of the United States population admits to having tried inhalants prior to fourth grade. The peak time for inhalant use appears to be between the seventh and ninth grades. Inhalants are sometimes referred to as "gateway" drugs, which means that they are one of the first drugs that people try before moving on to such other substances as alcohol, marijuana, and cocaine. Only a small proportion of those who have used inhalants would meet diagnostic criteria for dependence or abuse.
Males generally use inhalants more frequently than females. However, a National Household Survey on Drug Abuse has shown no gender differences in rates of inhalant use in youths between the ages of 12 and 17. Children younger than 12 and adults who use inhalants, however, are more likely to be male.
People rarely seek treatment on their own for inhalant dependence or abuse. In some cases, the child or adolescent is brought to a doctor by a parent or other relative who is concerned about personality changes, a chemical odor on the child's breath, or other signs of inhalant abuse. The parent may also have discovered empty containers of the inhaled substance in the child's room or elsewhere in the house. In other cases, the child or adolescent's use of inhalants is diagnosed during a medical interview, when he or she is brought to a hospital emergency room after overdosing on the inhalant or being injured in an accident related to inhalant use. Although inhalants can be detected in blood or urine samples, laboratory tests may not always confirm the diagnosis because the inhalants do not remain in the system very long.
Other substance use disorders are commonly seen among people diagnosed with inhalant dependence. The use of inhalants is usually secondary to the use of other substances, however; only occasionally are inhalants a person's primary drug of choice.
The use of other substances is not uncommon among people who abuse inhalants.
Intoxication from the use of such other substances as alcohol, sedatives, hypnotics (medications to induce sleep), and anxiolytics (tranquilizers) can resemble intoxication caused by inhalants. Furthermore, people under the influence of inhalants may experience hallucinations (typically auditory, visual, or tactile); other perceptual disturbances (such as illusions); or delusions (believing they can fly, for example).
Inhalant dependence and abuse
Chronic inhalant users are difficult to treat because they often have many serious personal and social problems. They also have difficulty staying away from inhalants; relapse rates are high. Treatment usually takes a long time and involves enlisting the support of the person's family; changing the friendship network if the individual uses with others; teaching coping skills; and increasing self-esteem.
Inhalant intoxication is often treated in a hospital emergency room when the affected person begins to suffer serious psychological (such as hallucinations or delusions) or medical consequences (difficulty breathing, headache, nausea, vomiting) from inhalant use. The most serious medical risk from inhalant use is "sudden sniffing death." A person using inhalants, especially if they are using the substance repeatedly in a single, prolonged session, may start to have a rapid and irregular heartbeat or severe difficulty breathing, followed by heart failure and death. Sudden sniffing death can occur within minutes. In addition, inhalant use can cause permanent damage to the brain , lung, kidney, muscle, and heart. The vapors themselves cause damage, but there are also dangerously high levels of copper, zinc, and heavy metals in many inhalants.
People who use inhalants may also be treated for injuries sustained while under the influence of inhalants or while using inhalants. For example, individuals intoxicated by inhalants may fall and injure themselves, or they may drive while intoxicated and have an accident. People who use inhalants may also die from or require treatment for burns because many inhalants are highly flammable. They may also need emergency treatment for suffocation from inhaling with a plastic bag over the head, or for choking on inhaled vomit.
Inhalant dependence and abuse
The course of inhalant abuse and dependence differs somewhat depending on the affected person's age. Younger children who are dependent on or abuse inhalants use them regularly, especially on weekends and after school. As children get older, they often stop using inhalants. They may stop substance use altogether or they may move on to other substances. Adults who abuse or are dependent on inhalants may use inhalants regularly for years. They may also frequently "binge" on inhalants (i.e., using them much more frequently for shorter periods of time). This pattern of use can go on for years.
The use of inhalants and subsequent dependence on the substance occurs among people who do not have access to other drugs or are otherwise isolated (such as prison inmates). Also, as with other substance use disorders, people who have greater access to inhalants are more likely to develop dependence on them. This group of people may include workers in industrial settings with ready access to inhalants.
Comprehensive prevention programs that involve families, schools, communities, and the media (such as television) can be effective in reducing substance abuse. The recurring theme in these programs is to stay away from drugs in the first place, which is the primary method of ensuring that one does not develop a substance use disorder.
Parents can help prevent the misuse of inhalants by educating their children about the negative effects of inhalant use. Both teachers and parents can help prevent inhalant abuse and dependence by recognizing the signs of inhalant use, which include chemical odors on the child's breath or clothes; slurred speech; a drunken or disoriented appearance; nausea or lack of appetite; and inattentiveness and lack of coordination.
American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 4th edition, text revised. Washington, DC: American Psychiatric Association, 2000.
Kaplan, Harold I., M.D., and Benjamin J. Sadock, M.D. Kaplan and Sadock's Synopsis of Psychiatry: Behavioral Sciences, Clinical Psychiatry. 8th edition. Baltimore: Williams and Wilkins.
American Psychiatric Association. 1400 K Street, Washington, DC 20005. (202) 682-6000. <http://www.psych.org> .
American Psychological Association. 750 First Street, NE, Washington, DC 20002-4242. (800) 374-2721. <http://www.apa.org> .
National Clearinghouse for Alcohol and Drug Information. (800) 729-6686. <http://www.health.org> .
National Institute of Mental Health. 6001 Executive Boulevard, Room 8184, MSC 9663, Bethesda, MD 20892-9663. (301) 443-4513. <http://www.nimh.nih.gov> .
National Institute on Drug Abuse (NIDA). 5600 Fishers Lane, Room 10-05, Rockville, MD 20857. Nationwide Helpline: (800) 662-HELP. <http://www.nida.nih.gov> .
National Library of Medicine. 8600 Rockville Pike, Bethesda, MD 20894. <http://www.nlm.nih.gov/medlineplus/drugabuse.html> .
Jennifer Hahn, Ph.D.