Inhalant disorders are a strange social phenomena that is prevalent in Mexico and the United States. It is estimated that 17 percent of American adolescents have abused inhalants and hospital admissions for inhalant disorders is common in Mexico among adults and adolescents, but with an unknown number of people involved, for some reason. In 2006, one US study estimated that over 2 million children, some as young as 12 years old admitted to inhalant abuse. This added up to an estimated 16.1 percent, more than those who abused other substances such as heroin, amphetamines, hallucinogens and cocaine.
The prevalence of inhalant abuse can readily be explained by the ease of gaining access to substances that are sold as common industrial or household products, but there is just scarce and poor study of this form of substance abuse, not enough to confirm whether easy access is the major cause of so many young children engaging in the abuse. This relative neglect of inhalant abuse has led to many conflicts and unresolved problems in diagnosing and defining what is called a "hidden epidemic".
The wide array of products and substances that are used in inhalant abuse may be the underlying problem with tracking down symptoms that can apply to all. Some substances might cause hallucinations, for example, while others may not.
The major consequences of ongoing inhalant abuse include: cardiac, renal, and liver toxicity and hepatorenal failure. There are bowel and bladder problems, T-Cell dysfunction, bone marrow suppression, irreversible heart problems, severe neurological and cognitive problems in addition to the psychiatric, social, legal, educational and human relationship problems.
Of the psychiatric problems and disorders, the lack of study has created a serious gap in the understanding of the dependence disorders vs the abuse disorders. The criterion that are used in the DSM-IV-TR have unresolved problems and validity issues with some of the descriptors, such as spending inordinate amounts of time in getting access to, being under the influence and recovering from the use of inhalants.
Basically, there are the two states of addiction: intoxication and withdrawal, along with increasing tolerance and a need for more in order to obtain the same results. With withdrawal there is currently poor consensus as to what the exact symptoms are. Unlike the other addictive substances, the current DSM does not include withdrawal as an addiction symptom for inhalants.
Behaviorally, there is the continued use of inhalants despite the damage, illness and destruction of life that it causes, along with the inordinate amount of time spent in obtaining, being under the influence of or recovering from the use of inhalants. This can involve absences from school, periods of absence, running away, or isolation from home, parents and friends and other problematic behaviors.
Then there are delusions and hallucinations that may or may not occur while intoxicated. If the person is seriously ill enough to be hospitalized or is engaging in delinquent behavior that leads to arrest, then there is hope that treatment for the physical and addiction problems can begin.
The US Consumer Product and Safety Commission (link below) has a detailed list of things to look for when inhalant abuse is suspected.
Matthew O. Howard and Brian E. Perron, "A Survey of Inhalant Use Disorders among Delinquent Youth: Prevalence, Clinical Features, and Latent Structure of DSM-IV Diagnostic Criteria", Biomed Central, 2009