A drainable ostomy pouch has an outlet. Reinforcing members at the outlet are deformable by application of manual pressure at their ends to distend the outlet. The lateral edges of the reinforcing members may be offset, which encourages the reinforcing members to consistently bend away from each other. A peelable distributed mechanical engagement fastener secures the outlet in a folded condition. The fastener parts are hook-hook type plastic extrusions, and provide a snap-engagement. A security flap is foldable under the outlet when in its folded condition. The outlet is released in two stages.