ia ▁is ▁referred ▁to ▁as ▁non - ul cer ▁d ys pe ps ia ▁and ▁its ▁diagn osis ▁is ▁established ▁by ▁the ▁presence ▁of ▁ep ig astr alg ia ▁for ▁at ▁least ▁ 6 ▁months , ▁in ▁the ▁absence ▁of ▁any ▁other ▁cause ▁explaining ▁the ▁sympt oms . ▁ ▁Post - in fect ious ▁ ▁Gast ro enter itis ▁increases ▁the ▁risk ▁of ▁developing ▁chron ic ▁d ys pe ps ia . ▁Post ▁inf ect ious ▁d ys pe ps ia ▁is ▁the ▁term ▁given ▁when ▁d ys pe ps ia ▁occurs ▁after ▁an ▁ac ute ▁g astro enter itis ▁in fection . ▁It ▁is ▁believed ▁that ▁the ▁underlying ▁causes ▁of ▁post - in fect ious ▁I BS ▁and ▁post - in fect ious ▁d ys pe ps ia ▁may ▁be ▁similar ▁and ▁represent ▁different ▁aspects ▁of ▁the ▁same ▁path oph ys i ology . ▁ ▁Function al ▁ ▁This ▁is ▁the ▁most ▁common ▁cause ▁of ▁chron ic ▁d ys pe ps ia . ▁More ▁than ▁ 7 0 % ▁of ▁people ▁have ▁no ▁obvious ▁organ ic ▁cause ▁for ▁their ▁sympt oms ▁after ▁evaluation . ▁Sym pt oms ▁may ▁arise ▁from ▁a ▁complex ▁interaction ▁of ▁increased ▁vis cer al ▁af fer ent ▁sens itivity , ▁g astr ic ▁delayed ▁empty ing ▁( g astro par esis ) ▁or ▁imp a ired ▁accommod ation ▁to ▁food . ▁An x iety ▁is ▁also ▁associated ▁with ▁functional ▁d ys pe ps ia . ▁In ▁some ▁people , ▁it ▁appears ▁before ▁the ▁on set ▁of ▁gut ▁sympt