Chemical Properties
White Solid
Uses
Labelled synthetic mu-opioid agonist. This is a controlled substance (opiate)
Brand name
Ultiva (Abbott).
Description
Ultiva was launched in Germany and the US for use in general anesthesia
and immediate post-operative pain management. This compound can be prepared
via the Michael addition of a 4,4-disubstituted piperidine to methyl acrylate. It
behaves as a specific μ-opiod agonist that is about 30 times more potent than its
chemical relative alfentanil. While its pharmacodynamic properties are similar to
other μ agonists, remifentanil has unique pharmacokinetic properties. It has a rapid
onset (1.6 min) and a rapid offset (5.4 min) independent of duration of administration.
This has been attributed to its rapid catabolism by general esterases to the
corresponding acrylic acid derivative. The metabolite has 0.01 to 0.0005 times the
activity of remifentanil and is excreted via the kidneys (80% recovery).
Originator
Glaxo Wellcome (UK)
Biochem/physiol Actions
Remifentanil hydrochloride is a mu opioid receptor agonist, anesthetic, and analgesic compound. Remifentanil was developed as an ultra-short-acting mu opioid receptor agonist with improved pharmacodynamic properties.
Pharmacokinetics
Remifentanil is much like alfentanil in its pharmacodynamic effects. It is a selective μ opioid agonist
with 15 to 20 times greater potency than alfentanil. Remifentanil has an onset of
action of 1 to 3 minutes when given intravenously. Its unique property is its rapid
offset of action, which is independent of the duration of administration of the compound. Thus, it is
very useful for titration of antinociceptive effect, followed by a rapid and predictable recovery time
of 3 to 5 minutes. The short duration of action is a result of the ester group, which has been
rationally designed into the substituent on the piperidine nitrogen. This ester group is rapidly
hydrolyzed to the inactive carboxylic acid by serum and tissue esterases, making the drug's
duration of action essentially independent of the liver or renal function of the patient. Remifentanil
is used extensively for analgesia associated with general anesthesia procedures. It often is used in
combination with injectable general anesthetic agents, such as midazolam or propofol.
