Aprepitant, sold under the brand name Emend among others, is a medication used to prevent chemotherapy-induced nausea and vomiting (CINV) and to prevent postoperative nausea and vomiting (PONV). It may be used together with ondansetron and dexamethasone. It is taken by mouth or administered by intravenous injection.Common side effects include tiredness, loss of appetite, diarrhea, abdominal pain, hiccups, itchiness, pneumonia, and blood pressure changes. Other severe side effects may include anaphylaxis. While use in pregnancy does not appear to be harmful, such use has not been well studied. Aprepitant belongs to the class of neurokinin-1 receptor antagonists medications. It works by blocking substance P from attaching to the NK1 receptors.Aprepitant was approved for medical use in the European Union and the United States in 2003. It is made by Merck & Co. It is on the World Health Organizations List of Essential Medicines. Medical uses
Aprepitant is used to prevent chemotherapy-induced nausea and vomiting (CINV) and to prevent postoperative nausea and vomiting (PONV). It may be used together with ondansetron and dexamethasone. Mechanism of action
Aprepitant is classified as an NK1 antagonist because it blocks signals given off by NK1 receptors. This, therefore, decreases the likelihood of vomiting in patients. NK1 is a G protein-coupled receptor located in the central and peripheral nervous system. This receptor has a dominant ligand known as Substance P (SP). SP is a neuropeptide, composed of 11 amino acids, which sends impulses and messages from the brain.
In addition, the new process also reduces the amount of solvent and reagents required by about 80% and saving an estimated 340,000L per ton of aprepitant produced.The improvements in the synthesis process have also decreased the long-term detriment to the natural environment associated with the original procedure, due to eliminating the use of several hazardous chemicals. History
It was approved by the US Food and Drug Administration (FDA) in 2003. In 2008, fosaprepitant, an intravenous form of aprepitant was approved in the United States. Research
Major depression
Plans to develop aprepitant as an antidepressant have been withdrawn. Subsequently, other trials with NK1 receptor antagonists, casopitant and orvepitant, have shown promising results.Beyond suggestions that PET receptor occupancy must not be used routinely to cap dosing for new medical indications for this class, or that > 99% human receptor occupancy might be required for consistent psycho-pharmacological or other therapeutic effects, critical scientific dissection and debate of the above data might be needed to enable aprepitant, and the class of NK1 antagonists as a whole,  to fulfill preclinically predicted utilities beyond CINV (i.e., for other psychiatric disorders, addictions, neuropathic pain, migraine, osteoarthritis, overactive bladder, inflammatory bowel disease and other disorders with suspected inflammatory or immunological components. However, most data remain proprietary and thus reviews on the expanded clinical potential for drugs like aprepitant range from optimistic to poor. References
External links
"Aprepitant". Drug Information Portal. U.S. National Library of Medicine.