Inhalant abuse and dependence are prevalent in adolescent population because inhalants are inexpensive, legal and accessible substance for youth. In Japan, the prevalence of inhalant abuse and dependence is gradually declining in these days, although inhalants can still become a "gateway drug" to other dependent substances such as cocaine and cannabinoids. Inhalant abuse causes show serious mental and somatic symptoms, and mortality in acute and chronic phases, while the abusers are ignorant about it. This paper reviews recent studies that investigate the symptoms and the treatments of inhalant abuse and dependence.