From compounding to formulation design

Assessment starts with the patient, route, required dose and available authorised product. Document swallowing difficulty, device use, age-related excipient restrictions and allergies. Another dosage form may meet the need, but the change requires formulation, dose-delivery and clinical-suitability evidence. Sharing an active ingredient alone does not establish therapeutic equivalence.

A formulation’s identity includes active chemical form, concentration, excipients, water, preservatives and starting products. Changing a salt, base or tablet type is not merely a naming change. The process specifies addition order, mixing, thermal stages and final volume or mass. The laboratory establishes that its equipment can achieve those conditions.

Mechanical mixing does not establish solubility, uniformity or chemical compatibility. Assess pH, crystallisation tendency, emulsion structure and preservative partitioning. A concentration stated for the original base may change after dilution. The two starting products’ expiry dates do not establish the mixture’s lifetime.

Appearance identifies some failures but does not establish strength, absence of degradants or microbiological suitability. Select method and criterion for the actual dosage form and use. A suspension needs redispersibility and device-delivered-dose assessment; at low strength, uniform mass does not imply uniform API. A critical specification failure requires quarantine and investigation.

The same rpm in a different mixer does not establish equivalent mixing. Scale, impeller diameter, time, geometry and temperature affect the process. Assess packaging-material or excipient-supplier changes against the attributes they could alter. Document applicability in F-013 before reusing the previous dating decision.