Inhalants are a broad range of drugs whose volatile vapors are taken in via the nose and trachea. They are taken by volatilization, and do not include drugs that are inhaled after burning or heating. For example, amyl nitrite and toluene are considered inhalants, but tobacco, marijuana, and crack are not.

While some inhalant drugs are used for medical purposes, as in the case of nitrous oxide (a dental anaesthetic), this article focuses on inhalant abuse as recreational drugs that are used for their intoxicating effect. Inhaling volatile substances because of their intoxicating effect is called huffing.

Inhalants can be classified by the intended function. Most inhalant drugs that are used non-medically are ingredients in household or industrial chemical products that are not intended to be concentrated and inhaled. A small number of recreational inhalant drugs are pharmaceutical products that are used illicitly.

Inhalants can also be classified by chemical structure. Classes include:

It is also possible to classify inhalants by the effect they have on the body. Many inhalants act primarily as asphyxiant gases, with their primary effect due to oxygen deprivation. Other agents may have more direct effects at receptors.

Heavy Heavy Low Low was a four piece Mathcore band from San Jose, California.

Formed in early 2004 in San Jose, California, Heavy Heavy Low Low began playing what may be called thrash (-core), then metalcore, before evolving into a decidedly more style, and now, with the release of their latest work, becoming much more indistinguishable as a genre, thus becoming experimental metal.

Their first release entitled Courtside Seats to the Greatest of All Time, was released by Twelve Gauge Records and featured their first single, "Inhalant Abuse Is Illegal And Can Be Fatal". They signed with New Weathermen Records, a division of Ferret Music, in mid-2006 and began work on their second full length. In September 2006, Everything's Watched, Everyone's Watching was released, which featured a few old songs re-done and remastered, along with numerous brand new tracks. Extensive and constant touring in support of the record ensued.

In early 2007, their out of print EP ... It?! was re-released via Ferret Music and was limited to 1,000 copies. This EP features numerous early recordings all from producer Sam Pura, including their single, "Tell Shannon Her Crafts Are Ready". It also includes current singer Robert Smith as well as previous singer Matthew Caudle. The release also features an exclusive B-Side track titled "Short Term Exposure, Long Term Damage".