Pill Identification by Imprints: S 521 Home Pill Identification by Imprints: S 521 2 results CETIRIZINE HCL 10 MG TABLET Side 1: S 521 Color: White Side 2: Shape: Rectangular (Rounded End) CETIRIZINE HCL 10 MG TABLET Side 1: S 521 Color: White Side 2: Shape: Rectangular (Rounded End) Other Popular Drug Imprint I3 KADIAN 54 533 cor 131 F19 25 IP 54 P 400 OR 606 MYLAN 6320 B 153 CM1 MP 573 318 Z 2083 S251 G 60 ADDERALL XR E4 512 ALEVE PM DAYPRO WPI 1118 NEURONTIN 600 TCL 086 VBZ 40 VP 077 R717 38AV GG C6 H 148 628 P2 TN 2 R 200 MP 272 cardizem CD 240 mg R207 logo and 718 I31 NL 771