Most of his relatively few coins have been found in northern Pakistan, indicating that he ruled a smaller principate around the lower Kabul valley.

R. C. Senior on the other hand places him as a successor of Menander, c. 135–125 BC, according to his interpretation of hoard findings.

Regardless of which period is correct, the fact that Nicias ages visibly on his coins seems to indicate some longevity to his rule.

Nicias struck Indian silver drachms of diademed or helmeted king with three reverses:

Even though Nikias ruled in the western parts of the Indo-Greek realm, no Attic coins have been found.His monograms generally match those of the kings Theophilus and Philoxenus, though one is shared with Thraso, the short-lived son of Menander I.