Insufflation (medicine)

For other uses, see Insufflation (disambiguation).

Insufflation (Latin insufflatio "blowing on" or "into") is the practice of inhaling a substance.^[1] Insufflation has limited medical use, but is a common route of administration with many respiratory drugs used to treat conditions in the lungs (asthma or emphysema) and paranasal sinus (allergy).

The technique is common for many recreational drugs and is also used for some entheogens. Nasal insufflation (snorting) is commonly used for many psychoactive drugs because it causes a much faster onset than orally and bioavailability is usually, but not always, higher than orally. This bioavailability occurs due to the quick absorption of molecules into the bloodstream through the soft tissue in the mucous membrane of the sinus cavity. Some drugs have a higher rate of absorption, and are thus more effective in smaller doses, through this route. Prodrugs, drugs that are metabolized or activated by the liver (such as hydrocodone), should not be insufflated, because they need to be metabolized by the liver to break down into the compounds that are active (drugs absorbed through the GI tract pass through the liver before entering the systemic circulation, where drugs which are insufflated are absorbed directly into the systemic circulation).

The intranasal route (administration through the nose) may allow certain drugs and other molecules to bypass the blood-brain barrier via diffusion through the olfactory epithelium and the perineural sheet or via retrograde axonal transport along olfactory and trigeminal nerves. This latter process probably implies endocytosis of the molecules. Using this route to the brain allows high concentrations of products in the olfactory bulb shortly after exposition and by diffusion to the entire brain. Therefore using this pathway allows a better biodisponibility the drug in the central nervous system, assuming that the molecule has the right physico-chemical characteristics to get through the nose and the epithelial defenses.^[2]

Medical uses

Medical procedure

Inert, nontoxic gases, such as carbon dioxide, are often insufflated into a body cavity, in order to expand workroom, or reduce obstruction during minimally invasive or laparoscopic surgery.

In the 18th century, the tobacco smoke enema, an insufflation of tobacco smoke into the rectum, was a common method of reviving drowning victims.^[3]

Intranasal (IN) administration of various lipid soluble medications is increasing in popularity. It is often used for treatment of pediatric patients or patients who are otherwise alarmed or frightened by needles, or where intravenous (IV) access is unavailable. In addition to a variety of nasal sprays readily available from pharmacies, some common medications delivered via IN include fentanyl, midazolam and naloxone. The time of onset for drugs delivered intranasally is generally only marginally slower than if given via IV.

Administering drugs

Psychoactive substances are often insufflated nasally for the purpose of intranasal absorption through the mucous membrane, which is often more rapid, or more complete, than gastrointestinal absorption. For a substance to be effective when insufflated, it must be water soluble so it can be absorbed into the mucous membranes. This practice is commonly referred to as snorting, bumping, railing, or doozing.^[4]

Although the majority of a dose of insufflated drug is taken up through the mucous membranes, some enters other parts of the gastrointestinal tract where it may also be absorbed. This is because some of the dose drips down the throat and into the stomach. This effect is commonly referred to as the 'drip' and is often unpleasant to taste.

Commonly insufflated psychoactive substances (for non-medical use) include:

• Dimethyltryptamine (DMT) - a psychedelic tryptamine, commonly insufflated during south american rituals.
• Cocaine (benzoylmethylecgonine) - a strong stimulant that is highly addictive; most commonly associated with drug insufflation
• Opioids - a class of analgesic drugs (including heroin, morphine, oxycodone, buprenorphine, hydromorphone, oxymorphone, and the synthetic meperidine and fentanyl).
• Amphetamines - another class of strong stimulants (including amphetamine, dextroamphetamine and methamphetamine) that are also highly addictive.
• Ritalin (methylphenidate) - another stimulant closely related to amphetamine, but often reported to have effects similar to that of cocaine when insufflated
• Ketamine - a dissociative anesthetic, used recreationally for its euphoric, anesthetic, and hallucinatory effects
• Phencyclidine - a dissociative anesthetic, commonly known as PCP or angel dust; no longer in common use because of reports of intensely negative experiences
• MDMA/Ecstasy - an entactogen that also possesses stimulant effects
• Zolpidem (Ambien) - a sedative hypnotic that can have various hallucinogenic effects with certain people and/or at high doses
• Tobacco snuff - contains nicotine, a mild stimulant that is highly addictive.

Various other drugs can be taken in intranasally for research purposes such as the neuropeptides MSH/ACTH, vasopressin and insulin.^[5]

Note: Some psychoactive substances such as benzodiazepines (valium, oxazepam, clonazepam) are water soluble to a small degree (about 350ml/1000 mg). Though this means they will be somewhat effective when insufflated, they will not be as readily absorbed into the mucous membrane as highly soluble substances such as amphetamines and opiates. Typically sublingual administration is preferred for this class of drugs.

Dangers

Many recreational drugs which are commonly insufflated such as cocaine, can cause damage to the nasal cavity and have even been known to destroy the nasal septum.^[6] Any damage to the inside of the nose is either because some insufflation highly constricts blood vessels – and therefore blood and oxygen/nutrient flow – to that area, or because the substance is physically caustic. A famous case where the septum was completely destroyed by cocaine was of Eastenders star Danniella Westbrook.

References

1. ^ http://www.merriam-webster.com/medical/insufflation
2. ^ William H. Frey. "Bypassing the Blood-Brain Barrier to Deliver Therapeutic Agents to the Brain and Spinal Cord." Drug Delivery Technology.
3. ^ Lawrence, Ghislaine (20 April 2002). "Tobacco smoke enemas". The Lancet 359 (9315): 1442. http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(02)08339-3/fulltext. Retrieved 2008-11-27.
4. ^ Definition of dooze, definition #4 ["http://www.urbandictionary.com/define.php?term=dooze"]
5. ^ Born J, Lange T, Kern W, McGregor GP, Bickel U, Fehm HL. (2002). Sniffing neuropeptides: a transnasal approach to the human brain. Nat Neurosci.5(6):514-6. doi:10.1038/nn849 PMID 11992114
6. ^ http://www.thesite.org/drinkanddrugs/drugsafety/drugsandyourbody/cokeandyournose