Dear Shaymaa

The dissolution test is performed for a specified time period, sampled and analyzed for amount of active ingredient dissolved (Q) in terms of percentage. This is the general study called S1stage. In this stage the amount dissolved from each unit (tab/cap/etc) placed in each jar of dissolution apparatus should not be less than Q plus 5%. If the limits obtained are below the actual limits, then it is recommended to study 6 additional units to test the dissolved amount of drug in total 12 units. This is called stage S2, where the average of 12 units should not be less than Q and also each unit should be less than Q-15%. If the results are disappointing by each unit below Q-15% or average of 12 units below Q, then we shall proceed to test by adding additional 12 units. Now total of 24 units are tested and their average amount of drug dissolved should not be less than Q,

Only 2 units may be less than Q-15% (some flexibility is officially given) and no unit should be less than Q-25%.

At this stage, flexibility is officially made available by average of 24 units should be equal to or more than Q but two units may be permitted up to Q-25%.

These stages are officially accepted by majority of regulatory bodies.

If you are satisfied with my answer please let me know. Thank you

For the prolonged tablets, "none is more than 10% of labeled content outside each of the stated ranges" means: For example , IF the range is 50%--70%.

then 40%--80% is the acceptable range.

Its a criteria / stage wise dissolution testing.

S1 - dissolution testing of 6 units

check the acceptance criteria if failed proceed for S2 with additional 6 units

check the acceptance criteria for 12 units in total (S1+S2) if failed proceed for S3 with additional 12 units

check the acceptance criteria for 24 units in total (S1+S2+S3) if failed

reject the batch