Questions in Practical 4

1. What are the objectives of the tests for uniformity of diameter and uniformity of

content ?

          The objective of the test for uniformity of diameter is to make sure the tablets produced are all uniform in size. This is important in the later process of tablet packaging either blister packaging or plastic container. The test for uniformity of content is to ensure that each tablet contains the similar amount of active ingredients and excipients so that each tablet contains correct dose of drugs. Hence, the bioavailability and efficacy carried out by the drug is the same for each of the tablet taken orally.

2. State the type of tablets and capsules that must be tested for uniformity of diameter and     uniformity of content.

          For uniformity of diameter, all tablets are applicable such as coated tablet, effervescence tablet and modified release tablet except enteric tablet, film-coated tablet and sugar-coated tablet. In this case, mostly capsules are applicable such as hard capsules, soft capsules, gastro-resistant capsules, modified-release capsules and cachets.

           For uniformity of content, normally single dose preparations are required. Tablets and capsules included are coated tablets, others than film-coated tablets containing 50mg or more of an active ingredient that comprises 50% or more of one tablet. Tablets or capsules have active ingredients less than 5% are needed. Liquid-filled soft capsules, solids packaged in single-unit containers with or without added substances and solutions for inhalation packaged in glass or plastic ampules are not applicable for testing uniformity of content.

3.  Give reasons for the non-compliance to test for uniformity of weight.

The reasons for the non-compliance to test for uniformity of weight are due to uneven feeding of granules into the die due to irregular movement of the lower punch that cause variation in capacity die space. This will result in unsatisfactory mix of ingredients at blending stage, and amount of ingredients cannot be weighed accurately. Segregation of  compound in formulation is also can happen.

4. Why does dissolution test suitable to be used for batch to batch quality control?

           Dissolution test suitable to be used for batch to batch quality control because it is easier to assess batch-to-batch consistency of solid oral dosage forms such as tablets which can be easily obtained and to predict in vivo drug release profiles. It also allows the prediction of time for complete release of the drug. This test is very effective and guarantee the quality of the pharmaceutical products by detecting deviations in manufacturing in order maintain to consistency and ensure optimum bioavailability so that the tablets can give the desired therapeutic effect.

5. Explain the difference found in the procedure for dissolution test in United States Pharmacopoeia and the British Pharmacopoeia.

            In Unites States Pharmacopoeia, typical acceptance criteria for the amount of active ingredient dissolved must be in the range of 75% to 80% whereas, in British Pharmacopoeia, the amount of active ingredient dissolved must not be less than 70%. In United States Pharmacopoeia, a retest may be carried out in three stages with different amount of tablets if the test failed. In British Pharmacopoeia, if the test failed, a retest may be carried out using the same number of units of tablets.