*Prices reflect U.S. average retail price

Naldemedine (INN, USAN; S-297,995, Symproic) is a peripherally-selective μ-opioid receptor antagonist developed by Shionogi which is approved for the treatment of opioid-induced constipation in adult patients with chronic non-cancer pain. Clinical studies have thus far found it to possess statistically significant effectiveness for these indications and to be generally well-tolerated with predominantly mild to moderate gastrointestinal side effects.... Wikipedia

Manufacturer's Website: Symproic                                                                                                                               Average retail cost: $498/month

Naloxegol (INN; PEGylated naloxol; trade names Movantik and Moventig) is a peripherally selective opioid antagonist developed by AstraZeneca, licensed from Nektar Therapeutics, for the treatment of opioid-induced constipation. It was approved in 2014 in adult patients with chronic, non-cancer pain... Wikipedia

Manufacturer's Website: Movantik                                                                                                                              Average retail cost: $480/month

Methylnaltrexone (MNTX, brand name Relistor), used in form of methylnaltrexone bromide (INN, USAN, BAN), is one of the newer agents of peripherally acting μ-opioid antagonists that act to reverse some of the side effects of opioid drugs such as constipation without affecting analgesia or precipitating withdrawals. Because MNTX is a quaternary ammonium cation, it cannot cross the blood–brain barrier, and so has antagonist effects throughout the body, counteracting effects such as itching and constipation, but without affecting opioid effects in the brain such as analgesia... Wikipedia

Manufacturer's Website: Relistor                                                                                                                              Average retail cost: $2,582/month

Alvimopan (trade name Entereg) is a drug which behaves as a peripherally acting μ-opioid antagonist. With the limited ability to cross the blood–brain barrier and reach the μ-opioid receptors of the central nervous system, the clinically undesirable effects of centrally acting opioid antagonists (like reversal of opioid-mediated analgesia) are avoided without affecting the intended blockade of μ-opioid receptors in the gastrointestinal tract... Wikipedia

Manufacturer's Website: Entereg                                                                                                                              Average retail cost: *

* This prescription is provided by your healthcare provider. It cannot be filled in a pharmacy and may be expensive.