What are Tablet formulations?
Join our community on Telegram!
Join the biggest community of Pharma students and professionals.
Tablets are solid dosage forms that consist of active pharmaceutical ingredients (APIs) and various excipients compressed into a specific shape and size. They are one of the most commonly used pharmaceutical dosage forms due to their convenience, stability, and ease of administration.
Tablet formulations refer to the various types of tablets that are commonly used to deliver medications, supplements, or other active ingredients. Tablets are solid dosage forms made by compressing or molding a powdered or granulated mixture of active pharmaceutical ingredients (APIs) and excipients. Excipients are inactive substances that aid in the processing and effectiveness of the tablet. The formulation of a tablet is essential to ensure its stability, bioavailability, and efficacy. As a GPAT aspirant, understanding the key aspects of tablet formulations is crucial for success in the examination. Let's delve into the details of tablet formulations:
Here are some common tablet formulations:
1. Immediate-Release Tablets: These tablets deliver the entire dose of the active ingredient(s) at once upon ingestion. They are designed to release the drug rapidly and provide an immediate therapeutic effect.
2. Extended-Release (Sustained-Release) Tablets: These tablets release the drug gradually over an extended period, allowing for prolonged therapeutic action and reducing the frequency of dosing. They may be designed to release the drug at a constant rate or in a controlled manner.
3. Enteric-Coated Tablets: Enteric coatings are used to protect the drug from stomach acid and ensure that it dissolves and releases the active ingredient in the intestine. This is often done to protect sensitive drugs from degradation in the acidic environment of the stomach.
4. Chewable Tablets: These tablets are designed to be chewed before swallowing, making them more convenient for patients who have difficulty swallowing regular tablets.
5. Effervescent Tablets: These tablets are designed to dissolve rapidly in water, releasing carbon dioxide and creating a bubbly or effervescent solution. They are often used for quick absorption or to improve palatability.
6. Sublingual and Buccal Tablets: These tablets are placed under the tongue (sublingual) or against the cheek (buccal) for absorption through the mucous membranes, bypassing the gastrointestinal tract and leading to faster drug action.
7. Dispersible Tablets: These tablets disperse in water before ingestion, making them easier to administer to patients who have difficulty swallowing whole tablets.
8. Bi-layer and Multi-layer Tablets: Tablets with two or more distinct layers, each containing different drugs or varying release rates, are used to deliver multiple drugs or achieve specific drug-release profiles.
9. Scored Tablets: Tablets with score lines are intended to be easily divided into halves or quarters to allow for more flexible dosing, especially when lower doses are required.
10. Film-Coated Tablets: These tablets have a thin film coating that may serve various purposes, such as improving appearance, taste, or ease of swallowing.
It's important to note that the specific formulation and design of tablets depend on the characteristics of the active ingredient(s), the desired therapeutic effect, and the needs of the patient. Pharmaceutical manufacturers carefully consider these factors when developing tablet formulations to ensure the safety and efficacy of the medications they produce.
Tablet Excipients:
- Binders: Binders are substances that provide cohesiveness to the tablet ingredients, ensuring proper tablet compression. Common binders include starch, cellulose derivatives (e.g., hydroxypropyl cellulose), and polyvinylpyrrolidone (PVP).
- Diluents/Fillers: Diluents add bulk to the tablet and ensure proper content uniformity. Commonly used diluents are lactose, microcrystalline cellulose, and dicalcium phosphate.
- Disintegrants: Disintegrants promote tablet disintegration into smaller particles upon contact with fluids, facilitating drug release. Examples include croscarmellose sodium and crospovidone.
- Lubricants: Lubricants reduce friction between the tablet and the die wall during compression, preventing sticking. Magnesium stearate and stearic acid are commonly used lubricants.
- Glidants: Glidants improve powder flow properties during tablet manufacturing. Talc and colloidal silicon dioxide are popular choices.
- Coloring Agents: Coloring agents (dyes or pigments) are used to provide visual identification and brand recognition. They have no therapeutic significance.
Tablet Manufacturing Techniques:
- Direct Compression: In this method, all the tablet ingredients, including the API and excipients, are blended and directly compressed into tablets. It is the simplest and most preferred method when the ingredients have good flow and compressibility properties.
- Wet Granulation: Here, the API and excipients are granulated using a liquid binder, dried, and then compressed into tablets. Wet granulation enhances powder flow and compressibility for challenging formulations.
- Dry Granulation (Roller Compaction): In dry granulation, the ingredients are compacted into large flakes or ribbons using a roller compactor, which are then milled into granules before compression.
- Effervescent Tablets: These tablets contain effervescent agents (e.g., citric acid and sodium bicarbonate) that release carbon dioxide upon contact with water, leading to effervescence and disintegration.
Conclusion:
Tablet formulations are an essential aspect of pharmaceutical science, and understanding their excipients, manufacturing techniques, and different types of tablets is vital for any GPAT aspirant. A clear grasp of these concepts will not only help in the examination but also prepare you for a successful career in the pharmaceutical industry or academia.
