Pills with imprint C4

The imprint C4 is used by 3 distinct products in our FDA label database, covering 3 different medicine(s). An imprint alone does not always identify a pill — makers reuse short codes — so always compare the colour, shape and size as well.

Imprint	Medicine & strength	Colour	Shape	Size	Labeler
C4	Chlorpromazine Hydrochloride 100 mg	Yellow	Round	10 mm	Remedyrepack Inc.
C4	Cyproheptadine Hydrochloride 4 mg	White	Round	7 mm
C4	Doxazosin Mesylate 4 mg	Yellow	Round	10 mm

Source: FDA label data via DailyMed/openFDA, export of October 29, 2026.