110355
Furthermore , as methylnaltrexone cannot cross the blood–brain barrier , it does not reverse the pain-killing properties of opioid agonists or cause withdrawal symptoms , but since a small portion of analgesia comes from the peripheral opioid receptors , it can increase pain from inflammatory conditions such as arthritis .
 arthritis
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
Answer:
 arthritis