Pill Identification by Imprints: M 1840 Home Pill Identification by Imprints: M 1840 1 result METHYLPHENIDATE ER 40 MG CAP Side 1: M 1840 Color: Yellow Side 2: 40 mg Shape: Oblong Other Popular Drug Imprint M 261 463 DAN 5440 NL 572 7033 MYLAN 6899 LCI 1338 PC23 MYLAN 186 L059 AN 54 US 5 SD 12 Dia B OV 111 E 771 4 9 G 3720 P58 A4 Y 46 WATSON 409 7.5 300 104 KEY 74 RF 28 93 4067 54 552 Z45 E1 or E2 HP 27 WPI 9 MIA 106 L2 or F BRISTOL 3030 M 722 VP Triax M050 72 L189