Or search: pi, virazole, ribavirin, interferon, medication, medicament, didanosine, dideoxyinosine, dideoxycytosine
1 Syllable: S
aisle, dial, Lisle, miles, rial, trial, vial
2 Syllables: SU
Bible, bridal, bridle, cycle, direful, final, idle, idol, libels, Michael, Michael's, Michel, primal, rifle, rival, sible, spinal, spiral, stifle, tidal, title, tribal, trifle, vital
2 Syllables: US
denial
3 Syllables: SUU
friable, liable, Lionel, pliable, sizable, sizeable, viable
3 Syllables: USU
archetypal, arrival, disciple, entitle, recital, reprisal, revival, survival, unbridled, unrivalled, vaginal
4 Syllables: USUU
advisable, assignable, definable, desirable, excitable, inviolable, parietal, reliable
4 Syllables: UUSU
suicidal
5 Syllables: UUSUU
inadvisable, indefinable, indescribable, recognizable, undeniable, undesirable, unreliable
6 Syllables: UUUSUU
unjustifiable, unrecognizable

Found 68 words across 9 groupings. Skipped 28 excess words of a similar stem.