I. Tablet quality inspection items mainly include appearance, weight variation, disintegration time, dissolution rate, content uniformity, and microbial limits.
(1) Tablet Appearance
Tablets should be intact and smooth, with a uniform color, and possess the appropriate hardness and abrasion resistance to prevent wear or breakage during packaging and transportation.
(2) Tablet Weight Variation
Weight variation is checked by sampling and weighing individual tablets and comparing the actual weight with the labeled weight. The difference must not exceed the allowable range specified in the pharmacopoeia.
(3) Tablet Hardness and Friability
The hardness and friability of tablets are important indicators affecting their quality. Hardness refers to the tablet’s resistance to breakage, usually measured by applying pressure, while friability reflects the tablet’s resistance to abrasion and vibration. Appropriate hardness ensures that tablets are not easily broken during production, transportation, and storage, and also affects the rate of drug release. Excessive hardness may lead to slow drug release, while insufficient hardness may cause tablets to break during packaging and transportation. Therefore, during tablet production, hardness and friability need to be reasonably controlled to ensure quality and efficacy. If tablets repeatedly show abnormal breakage during inspection, further optimization is required, which may involve combining hardness testing with formulation process analysis to identify the root cause of the issue.
(4) Tablet Disintegration Time
Disintegration time is the time required for a solid dosage form (such as tablets, capsules, etc.) to completely disintegrate or dissolve in a specified medium (simulating the gastrointestinal environment). The test environment temperature is 37±1℃.
Disintegration Time Requirements for Different Types of Tablets
Ordinary Tablets: Should completely disintegrate within 15 minutes.
Film-coated Tablets and Hard Capsules: Disintegration time is 30 minutes.
Sugar-Coated Tablets and Soft Capsules: The disintegration time is extended to 1 hour.
Enteric-coated Tablets: Must remain undisintegrated in an acidic environment for 2 hours, followed by complete disintegration in a buffer solution within 1 hour.
Drops: Dissolution time is 30 minutes for ordinary types and extended to 1 hour for coated types.
(5) Content uniformity of tablets
Content uniformity of tablets refers to the degree to which the amount of active pharmaceutical ingredient contained in each tablet of a small-dose or single-dose solid dosage form (such as tablets, capsules, etc.) conforms to the labeled amount. It is an essential indicator for evaluating the quality of pharmaceutical preparations, especially for small-dose drugs, as it can more accurately reflect the uniformity of drug distribution.
Content uniformity checks the uniformity of drug content in a single dose, ensuring the stability of the active ingredient dosage in each tablet and thereby ensuring the safety and effectiveness of the medication.
Compared with traditional weight variation checks, it can more accurately control the quality of small-dose drugs.
(6) Dissolution and release of tablets
Dissolution refers to the rate and extent to which a drug dissolves from solid dosage forms, such as tablets or capsules, in a specified solvent. It is a crucial indicator for evaluating the quality of pharmaceutical preparations, as it directly affects the bioavailability and therapeutic efficacy of drugs. Dissolution testing typically involves placing the formulation in a specific volume of solvent (such as simulated gastric or intestinal fluid), stirring or shaking it for a particular time, and then measuring the concentration of the drug dissolved in the solvent. Release rate, on the other hand, focuses more on describing the drug release behavior of sustained-release, controlled-release, or different formulations with special release characteristics. These formulations are designed to release the drug at a predetermined rate and pattern, achieving a specific therapeutic purpose.
(7) Tablet Effervescence Volume
Tablet effervescence volume refers to the volume of foam produced by an effervescent tablet under specific conditions, primarily used to assess its disintegration performance. The effervescence volume of vaginal effervescent tablets must meet pharmacopoeia standards, specifically requiring an average effervescence volume of not less than 6 ml, and no more than two tablets with a volume less than 4 ml.
(8) Tablet Dispersion Uniformity
Tablet Dispersion Uniformity is an essential indicator for assessing the quality of tablets, especially in the preparation and clinical application of dispersible tablets. Dispersion uniformity testing must be performed using specific instruments and standardized procedures to ensure rapid disintegration and uniform dispersion of the drug in vivo, thereby improving bioavailability.
(9) Microbial Limits for Tablets
Microbial limits for tablets refer to the limits set for the degree of microbial contamination in non-sterile tablets, aiming to control the number of microorganisms and ensure the safety of the medication.
The results of microbial limit tests must comply with the standards for microbial contamination control of non-sterile preparations.
II. Packaging and Storage of Tablets
(1) Packaging of Tablets
Tablets should generally be sealed in packaging to prevent moisture and air exposure, thus preventing deterioration and ensuring compliance with hygiene standards. Blister packaging and bottle packaging are commonly used. For some light-sensitive tablets, light-proof containers, alu-alu blister packs, or blister packs with pillow packing should be used.
(2) Storage of Tablets
Tablets should be stored in a sealed environment, taking into account the effects of temperature, humidity, and light. Light-sensitive tablets should be stored away from direct light. Tablets that are easily decomposed by moisture should be placed inside a container with a desiccant to prevent moisture from affecting them.
Tablet production must strictly adhere to GMP standards, with regular quality monitoring of raw materials, excipients, and finished products. During storage, tablets should be sealed and placed in a dry environment to prevent moisture absorption or component degradation. Before use, check the packaging integrity and expiration date and follow the instructions carefully. If any abnormalities are observed, such as discoloration, swelling, or an unusual odor, discontinue use immediately.