The Collaborative International Dictionary of English v.0.48:

Dyspeptic \Dys*pep"tic\, Dyspeptical \Dys*pep"tic*al\, a.
   Pertaining to dyspepsia; having dyspepsia; as, a dyspeptic or
   dyspeptical symptom.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Dyspeptic \Dys*pep"tic\, n.
   A person afflicted with dyspepsia.
   [1913 Webster]

WordNet (r) 3.0 (2006):

dyspeptic
    adj 1: suffering from dyspepsia
    2: irritable as if suffering from indigestion [syn:
       atrabilious, bilious, dyspeptic, liverish]
    n 1: a person suffering from indigestion

Moby Thesaurus II by Grady Ward, 1.0:

65 Moby Thesaurus words for "dyspeptic":
   allergic, anemic, apoplectic, arthritic, bilious, bitter,
   cancerous, case, chlorotic, choleric, colicky, consumptive,
   dropsical, edematous, embittered, encephalitic, epileptic,
   hot-tempered, ill-humored, ill-natured, incurable, inpatient,
   invalid, jaundiced, laryngitic, leprous, luetic, malarial,
   malignant, measly, nephritic, neuralgic, neuritic, outpatient,
   palsied, paralytic, patient, phthisic, pleuritic, pneumonic, pocky,
   podagric, rachitic, rheumatic, rickety, rusty, scorbutic,
   scrofulous, shut-in, sick person, sour, sour-tempered, soured,
   spastic, sufferer, tabetic, tabid, terminal case, the sick,
   tubercular, tuberculous, tumorigenic, tumorous, valetudinarian,
   vinegarish