Tablets and Quality Control

• Tablets are solid dosage forms of medicaments, with or without excipients.
• They're prepared by compression or molding.
• Tablets are designed for oral administration.
• They are intended for local or systemic effects.
• Compressed tablets are characterized by shape, diameter, thickness, weight, hardness, friability, disintegration time and dissolution characteristics.

Quality Control (QC)

• Quality control is a subset of quality assurance (QA).
• QC involves sampling, testing, and documentation.
• It occurs during and after manufacturing.
• QC monitors actual quality performance and compares it to pharmacopeia standards.
• Standards include USP/IP/BP.
• The aim is to identify and correct deviations from standards.
• Quality control is a procedure to ensure a product meets requirements.
• It confirms the product is reproducible.

Why quality control tests are needed

• Quality control ensures safety, potency, efficacy, stability, patient acceptability, and patient compliance.
• The tests check if a tablet meets quality standards.
• It verifies that quality parameters are within acceptance limits.

Evaluation of secondary & primary package

• Package specifications include:
• Type of container.
• Material of container.
• Color.
• Shape.
• Size and dimension.
• State of package.
• Written material (batch no., man. date, exp. date).

Types of quality control tests

• Official tests are described in official compendia.
• Official tests are standardized with stated limits for acceptance.
• They assess content and in-vitro release of active ingredients.
• Unofficial tests are performed on tablets but not listed in official compendia.
• They relate to quality attributes such as hardness, friability, and thickness.
• Some unofficial tests lack official acceptance/rejection limits.
• These limits may vary by manufacturer and formulation.

Unofficial (Non-Pharmacopoeial) Tests

• General appearance tests assess visual identity and elegance.
• These are important for consumer acceptance.
• Tests ensure batch-to-batch and tablet-to-tablet uniformity.
• They monitor trouble-free manufacturing.
• Evaluation includes size, shape, color, odor, taste, surface texture, physical flaws, and markings.

Shape and Size

• Tablet shape and size can be dimensionally described, monitored, and controlled.
• Tooling determines these characteristics during compression.
• Tablets are often discoid, but can also be oval, oblong, round, cylindrical, or triangular.
• Surfaces can be flat, round, concave, or convex.
• Deep concave oval or capsule-shaped tablets are usually sugar coated.
• Deep concave shapes are selected for coating reasons.
• Their shape lends itself to rolling and interaction with liquid in coating pans.
• Tablets may be scored in halves or quadrants for easier dose adjustment.
• Tablets range from 1mm to 22mm.
• Mini-sized tablets: 2-5 mm (e.g., buccal tablets).
• Standard/conventional tablets: >5 mm (e.g., 500 mg paracetamol is 13 mm).
• Largest tablets: Around 1 inch or 25.4 mm (e.g., effervescent tablets).

Unique Identification Markings

• Techniques, such as embossing or engraving, aid rapid product identification.
• Types of informational marking placed on a tablet include:
  • Company name/symbol.
  • Product code (e.g., NDC number).
  • Product name.
  • Product potency.

Organoleptic Properties

• Color allows rapid identification and consumer acceptance.
• Color must be uniform within a tablet, also from tablet to tablet, and from lot to lot.
• Nonuniformity ("mottling") is an aesthetic disadvantage.
• Consumers may recognize nonuniformity, indicative of poor quality.
• Odor indicates stability.
• examples of odor issues include acetic acid (degrading aspirin), drug odors (vitamins), added ingredients (pleasant odors), and dosage form (film-coated tablets).
• Taste is important for chewable tablets.
• Companies use taste panels for flavor preference testing.

Physical Flaws

• Capping: Partial or complete separation of tablet crowns.
• Lamination: Separation of a tablet into distinct horizontal layers.
• Picking: Small amounts of material stick to and are removed by a punch.
• Sticking: Tablet surface adheres to the punch face or die wall during compression.
• Binding: Tablet adheres, seizes, or tears in the die; hindering ejection.
• Cracking: Small, fine cracks on the tablet surface.
• Chipping: Breaking of tablet edges during pressing or handling.
• Double impression: Monogram or logo appears twice on the tablet surface.

Official (Pharmacopoeial) Tests

• "Uniformity of dosage form" describes the uniformity of drug substance amounts among dosage units.
• It's a pharmacopoeial test for tablet evaluation.
• Uniformity is demonstrated through weight variation or content uniformity.

Weight Variation Test

• Weight variation is an important quality control parameter.
• It’s related to the content uniformity of a drug.
• It's applicable to tablets with 25 mg or more of drug, or if the drug substance is 25% or more of the dosage form unit.
• It detects tablets where average or individual weight falls outside accepted limits.
• The test is performed for uncoated and film-coated tablets.
• The procedure involves:
  • Weighing 20 tablets after cleaning.
  • Determining the weight of each tablet and calculating the average weight of all 20.
  • Calculating the percentage deviation of each tablet.

Official Weight Variation Standards

• According to USP, BP & IP, standards for uncoated tablets are:
  • Tablet weight 80 mg or less: ±10%.
  • More than 80 mg or less than 250 mg: ±7.5%.
  • 250 mg or more: ±5%.
• According to USP:
  • Tablet weight 130 mg or less: ±10%.
  • 130 mg to 324 mg: ±7.5%.
  • More than 324 mg: ±5%.
• Note: No more than two individual weights can deviate from the average by more than the percentage listed; no weight can deviate by more than twice that percentage.

Causes of Weight Variation

• Differences in the size of compressed granules (presence of too large or fine granules).
• Poor flow (causes incomplete filling of the die).
• Poor mixing (non-uniform distribution of lubricants and glidants).
• Unequal length of lower punches causes different filling of each die.