Stability Testing Question & Answers –Container orientation

What is the recommended container orientatation of stability samples (liquids, solutions,semi solids and suspensions) for US market ?

There are two USFDA guidance’s, which gives inputs on container orientations during stability study. 1.According to USFDA Guidance “ANDA Submissions — Content and Format Guidance for Industry” "For primary batches of liquids, solutions, semi-solids, and suspensions, the product should be placed into worst-case and non-worst-case scenarios. For post-approval stability studies, the applicant should pick the worst-case orientation for the study". 2.According to “USFDA Guidance for industry ANDAs: Stability Testing of Drug Substances and Products - Questions and Answers” "For primary batches of liquids, solutions, semi-solids, and suspensions, the product should be placed into an inverted (or horizontal) position and an upright (or vertical) position. For routine stability studies, the applicant should pick the worst case orientation for the study".