Where Is Fentanyl Absorbed?

Fentanyl is an incredibly powerful synthetic opioid, and it’s used in medical settings for a variety of reasons including for the treatment of severe and chronic pain in people who are resistant to the effects of other opioids. There are different ways fentanyl can be administered including in a transdermal patch form, and orally.

While fentanyl certainly has therapeutic pain relieving benefits, it’s also one of the most commonly abused drugs in the U.S. The majority of illicitly obtained fentanyl comes from China, where there are laxer pharmaceutical regulations. Fentanyl has a high potential for abuse, particularly because its effects occur rapidly but last only a short time, and also because it can create a euphoric high, particularly when taken in larger doses.

Despite the prevalence of fentanyl use, there are still many things people don’t know about this opioid with regard to how it works. Common questions people have are where is fentanyl absorbed, and where is fentanyl metabolized?

Where Is Fentanyl Absorbed?
To answer the first question of where fentanyl absorbed, it’s important to realize that it quickly crosses the blood-brain barrier, regardless of how it’s taken. Because of the lipophilicity of the drug, it creates a fast response and effect on the central nervous system, which is why people feel a rapid, euphoric high, particularly when they first start using it. Other effects that occur quickly include respiratory depression, but there’s also the potential for dangerous side effects like seizures, hypotension, and coma. Many of the effects and properties of fentanyl, including in the development of tolerance, are similar to morphine. The specifics of where fentanyl is absorbed are based on the way it’s administered. When fentanyl is given intravenously because of its high lipid solubility, the effects are more localized than morphine. When fentanyl is given orally, it’s absorbed through the sublingual mucosa, and when fentanyl is given in lozenge form, it’s absorbed through the oral mucosa primarily. When fentanyl is administered by transmucosal routes, it tends to reach the brain very quickly, and the effects are dependent on the individual’s pH. There are also some options that include nasal spray and inhalers, but they’re absorbed quickly and may be unsafe because of that.
The patch is one of the more common ways to administer fentanyl, so it’s particularly relevant to the conversation of where is fentanyl absorbed and where is fentanyl metabolized. The fentanyl transdermal patch includes a gel infused with a certain dose of fentanyl, and when someone applies it to their skin, it can provide continuous pain relief, usually for a period of 48 to 72 hours. These patches are most often prescribed to treat palliative pain relief for cancer patients and to help manage pain following an operation. For this type of fentanyl to be effective, it has to be absorbed by the skin and then build up, and it may take up to 24 hours for it to start working. Unfortunately, with this method of fentanyl absorption, there are opportunities for abuse including applying more than one patch at a time, changing the patches more often than what’s prescribed, inserting patches rectally, or extracting the fentanyl from the patch and then injecting it, among others.
To answer the question of where is fentanyl absorbed: it really depends on the way it’s administered. What about where is fentanyl metabolized? First, fentanyl is very quickly metabolized by the liver, and this metabolization is because of three metabolites which are norfentanyl, hydroxfentanyl, and hydroxynorfentanyl. When someone takes fentanyl, it’s estimated that around 85% of a dose would be excreted via the urine in a three to four day period, at least when it’s taken intravenously. When fentanyl is given transdermally or in oral doses, it can be detected in the urine for around 24 hours. Also pertinent when discussing where is fentanyl metabolized and where is fentanyl absorbed is looking how long it stays in your system. The half-life of fentanyl in terms of elimination is around two to four hours, so it would take anywhere from 11 to 22 hours to leave the system of the user in most cases when taken intravenously. When it’s taken as a patch or lozenge, it’s half life is around seven hours and it could take 36 hours to leave the system of the user completely. When fentanyl is metabolized it leaves behind metabolites, which linger in the system of the user longer.
Where Is Fentanyl Absorbed?
How Would You Rate This Page?