Fospropofol
Fospropofol, often used as the disodium salt, is an intravenous sedative-hypnotic agent. It is currently approved for use in sedation of adult patients undergoing Laboratory [diagnosis of bacteria|diagnostic] or therapeutic procedures such as endoscopy.
Clinical applications
Several Water-soluble#Solubility of [ionic compounds in water|water-soluble] derivatives and prodrugs of the widely used intravenous anesthetic agent propofol have been developed, of which fospropofol has been found to be the most suitable for clinical development thus far. Purported advantages of this water-soluble chemical compound include less pain at the site of intravenous administration, less potential for hyperlipidemia with long-term administration, and less chance for bacteremia. Often, fospropofol is administered in conjunction with an opioid such as fentanyl.Clinical pharmacology
Mechanism of action
Fospropofol is a prodrug of propofol; as an organophosphate it is metabolized by alkaline phosphatases to phosphate and formaldehyde and the active metabolite, propofol.Pharmacodynamics
Pharmacokinetics
Initial trial results on fospropofol pharmacokinetics were retracted by the investigators. As of 2011, new results were not available.Distribution
Following the administration of fospropofol 12.5 mg/kg loss of consciousness takes about four minutes, compared to one arm-brain circulation time with propofol 2.5 mg/kg.Metabolism
Fospropofol is metabolized in the liver by alkaline phosphatases to propofol, formaldehyde, and phosphate. The hepatic metabolism of this prodrug to an active metabolite means that peak plasma levels of propofol after the administration of a bolus of fospropofol are lower than for an equipotent dose of propofol and also that its clinical effect is more sustained. These features can be desirable for endoscopic procedures such as esophagogastroduodenoscopy, colonoscopy, bronchoscopy, as well as for some surgical procedures done under local or regional anesthesia.Propofol is further metabolised to propofol glucuronide and quinol glucuronide. Formaldehyde is a known carcinogen but label information states that serum formaldehyde levels are similar to background levels. No long term studies have been done on the cancer risks. The parent drug has a terminal elimination half-life of 0.88+/-0.08 hours, which is non-renal.