UNIFORMITY OF DOSAGE UNITS

uniformity of dosage unit (UOD)  can be known as the uniformity in the amount of the drug substance among dosage units

It (UOD) can be determined by two methods

1. By content uniformity (CU) -  based on the assay / amount of the individual content of drug substance(s)

2. Weight variation (WV) - Name itself showing weight as you might understand. (It prefers when a dosage unit contains more than 25% of Active substance(s).



Generally, When a tablet / capsule contains more than 25% of active substance, unnecessary to carry Content uniformity when tablet as in core where as coated tablets other than film coated require to send for CU (content uniformity). Though, In pharmaceutical industry , wish to send for CU even for core.

Content uniformity:

Required for dosage forms as follows
1. Core tablet(s) less than 25% of active substance and Coated tablets other than film coated tablets that comprises  25% or more of one tablet.
2. Trans dermal system
3. Suspension / Emulsion / gels in unit-dose container
4.Inhalations
5.Suppositories
6. Soft gelatin capsules



Table: Application of CU and WV tests for dosage forms (Source from USP)