A sachet is a flat flexible pouch; a stick pack is a narrow, elongated pack commonly formed with a longitudinal seal and end seals. Both can contain a single measured dose. Pack width, fill characteristics and the opening method influence which configuration suits the product.
| Decision | Sachet | Stick pack |
|---|---|---|
| Geometry | Flat pouch with a wider face | Narrow, elongated format |
| Filling interface | Pouch opening and dose distribution | Narrow fill path and available headspace |
| Label layout | Wider face for text and coding | Long, narrow print area |
| Opening assessment | Tear position and controlled discharge | Tear position and discharge through a narrow opening |
| Seal assessment | Perimeter seal layout | Longitudinal and end-seal layout |
Establish filling and sealing requirements
Specify the medicine’s dosage form, target fill and acceptable variation. Check whether the material bridges, adheres to the dosing path or reaches the seal area. For liquids, examine drips and wet seals; for powders, examine dust and product caught at the seal.
US 21 CFR 211.94 ties container suitability to protection of the drug and compatibility with it. Material selection and seal design should therefore be evaluated for the actual formulation and intended storage conditions.
Keep output units explicit
Ask suppliers to distinguish cycles per minute, the number of active lanes and finished packs per minute. For four lanes producing one pack each per cycle at 30 cycles/min, gross output is 4 × 30 = 120 packs/min before rejects and stoppages. A machine acceptance test uses the agreed product and pack configuration.
Record good packs separately from total packs produced. A faster cycle setting is useful only if fill, sealing and coding remain within the agreed acceptance criteria.
Qualify the operating range
EU GMP Annex 15, section 7.2, calls for qualification at defined minimum and maximum settings for critical primary-packaging parameters such as temperature, speed and sealing pressure. Test how the selected material and product behave across the agreed range, including start-up and restart conditions where relevant.
The line-selection guide connects these requirements with available production time. Use the URS checklist to specify the evidence and acceptance check for each requirement.
