On the basis of the above and in consideration of the formulation and posology from the treatment guidelines;
- Zinc sulfate tablets should be stored in blister packaging (not bottles or multi-dose containers).
- Zinc formulations should be distributed in quantities sufficient for treatment for 10-14 days i.e., at least 5- 14 tablets per blister packaging or 50-140 mL as oral solution.
- The strength of the formulation on the labelling should always be in terms of zinc sulfate and elemental zinc e.g. zinc (as sulfate monohydrate) 20mg tablets. If the USP standard is claimed, the composition in the SmPC and PIL should include the strength in terms of the API form, e.g. “Each tablet contains 54.9 mg zinc sulfate monohydrate equivalent to 20 mg of zinc”.
- As specified in the Ph.Int. monograph, “Liquid Preparations for Oral Use”, oral solutions in multi-dose containers are required to have a device capable of uniformly dispensing the required range of doses (5 to 10 ml for 10mg/5ml solution). A sample of the device must be provided, along with specifications (with IR identification of the material); data to demonstrate the uniformity of mass of doses delivered by the measuring device at the lowest intended dose, as outlined in the monograph referenced above; and the “Instructions on Use and Handling” should provide clear instructions.
- A one-time study of extractables (e.g. USP <661> and <671>), leachables (either a study or certification that the materials of construction for packaging components in contact with the product meet the requirements for indirect food additives, e.g. 21 CFR 174-186) and water loss (e.g. USP <671>) is required for oral solutions in plastic bottles.
