TABLET | TYPES OF TABLETS | ADVANTAGES | DISADVANTAGES

This presentation covers the tablet dosage for m introduction with classification of tablets .

1. CONTENT Introduction Advantages and Disadvantages tablets Types of tablets Reference :- Lachman/Lieberman’s , Industrial Pharmacy , Fourth Edition ,CBS Publishers & Distributors Pvt Ltd Page No – 449 – 546 TABLET

2. According to the Indian Pharmacopoeia :-Pharmaceutical tablets are solid, flat or biconvex dishes, unit dosage form, prepared by compressing a drugs or a mixture of drugs, with or without diluents. They vary in shape and differ greatly in size and weight, depending on amount of medicinal substances and the intended mode of administration. It is the most popular dosage form and 70% of the total medicines are dispensed in the form of Tablet. All medicaments are available in the Tablet form except where it is difficult to formulate or administer. DEFINITION

3. PRODUCTION ASPECTS Large scale production at lowest cost Easiest and cheapest to package and ship High stability (chemical, mechanical & biological) Lightest and most compact formulation aspects Greatest dose precision with least content variability Tend to give special release profile products e.g. enteric or delayed release tablets Product identification is cheap – embossing or monogrammed punch face 2. PATIENT ASPECTS Ease of handling Coating can mask unpleasant tastes & improve patient acceptability. ADVANTAGES

4. Some drugs resist compression into dense compacts owing to amorphous nature, low density character. Difficult to swallow in case of children, Old age patients and unconscious patients. Drugs with poor wetting & slow dissolution may be difficult or impossible to formulate and manufacture as a tablet that provide adequate or full drug bioavailability. Bitter taste drugs , drugs with an objectionable odour , or sensitive to oxygen or moisture may require encapsulation or entrapment prior to compression or the tablets may require coating. DISADVANTAGES

5. 1.Oral tablets for ingestion Compressed tablets or standard compressed tablets Multiple compressed tablets Layered tablets Compression coated tablet Chewable tablet Sugar and choclate coated tablet Film coated tablet Repeat action tablet Delayed action tablet & enteric coated tablet Controlled release tablets TYPES & CLASSES OF TABLET

6. 2.Tablets used in the oral cavity Buccal & sublingual tablets Troches & lozenges Dental cones 3. Tablets administered by other routes Implantation tablet Vaginal tablet 4.Tablets used to prepare solutions Effervescent tablet Dispensing tablet Hypodermic tablet Tablet triturates TYPES & CLASSES OF TABLET

7. COMPRESSED TABLET Uncoated tablet intended to provide rapid disintegration & drug release. To exert local effect Made by wet granulation, double compaction or direct compression. These drugs are typically water insoluble e.g Antacid & Adsorbents. ORAL TABLETS FOR INGESTION

8. Multiple compressed tablets (Layered tablets & Compression coated tablet ) Two components or three layer tablets Tablets with in a tablet Tablets with in a tablet with in a tablet Intended to separate physically or chemically incompatible ingredient To produce repeat action & Prolonged action products Complete physical separation is required for stability purpose in case of three layer tablets ORAL TABLETS FOR INGESTION

9. CHEWABLE TABLET Intended to be chewed in mouth. Most commonly used chewable tablet in market for children. “Chewable Aspirin tablet” Antacid tablets, Anthelminthics Disintegrant not required Activity of antacid increases when  No. of particle increases. SUGAR & CHOCLATE COATED In preparation of multivitamin and multivitamin mineral combination. Permit separation of incompatible ingredient FILM COATED TABLET Alternative procedure for drugs not require coating Coating material: plasticizer + surfactant  Facilitate spreading ORAL TABLETS FOR INGESTION

10. POLYMER Hydroxy Propylcellulose (HPC) And HP Methyl Cellulose(HPMC) Dissolve In Water With Appropriate Plasticizer  Immediately Release Film Coating Colloidal Dispersion Of Ethyl Cellulose In Water  Slow Or Controlled Released Film Coating 30% Ethyl Cellulose Dispersion Aqua Coat By Fmc Corporation. Adv. Of Film Coated Over Sugar Coated Tablet Mechanical Strength Little Increase In Tablet Weight Loss Likely To Be Mistaken For Candy. ORAL TABLETS FOR INGESTION

11. REPEAT ACTION TABLETS Core tablet is coated with shellac or with enteric polymer. For the purpose to release the drug in intestine(avoid release in stomach) DELAYED ACTION TABLET & ENTERIC COATED TABLET Intended to release a drug after some time delay or after the tablet has passed through one part of the GI tract into another Not all delayed action tablets are enteric or intended to produce enteric effect Enteric coating polymer: Cellulose acetate phthalate, polyvinyl acetate phthalate, HPMC phthalate . Contains dicarboxylic acid and phthallic acid  In esterified form  Being acid ester  Insoluble in gastric media Mechanism  lose of integrity the polymer film ORAL TABLETS FORINGESTION

12. BUCCAL & SUBLINGUAL TABLETS These tablets intended to be held in mouth . Release drug for absorption. These tablets intended to be held between the cheek and teeth or in the cheek pouch (buccal tablet ) or beneath the tounge (sublingual tablets) Not to disintegrate but too slowly dissolve typically over a 15- 30 min period. Intended to produce systemic effect(drug absorption from oral mucosa directly enters into blood circulation) : Avoid 1ST pass metabolism e.g steroid and hormones TABLETS USED IN THE ORAL CAVITY

13. TROCHES & LOZENGES Made by [Candy molding process] Intended to exert local effect in mouth or throat. No disintegrant is added. Larger amount of binder and no disintegrant  t o control sore throat + coughing DENTAL CONES Intended to be placed in empty socket remaining following tooth extraction. Purpose  to prevent the multiplication of bacteria in the socket of tooth extraction. Vehicles used:- NaHCO3, NaCl, amino acids. Formulated to dissolve in presence of small volume of serum or fluid over 20-40 minute period. TABLETS USED IN THE ORAL CAVITY

14. IMPLANTATION TABLET (DEPOT TAB.) E.G., NEXLPANON Implant intended for subcutaneous implantation. Prolong drug release from months to year at constant drug release rate Tablets are small, cylindrical or rosette shaped & not more than 8 mm in length. Kern injector (special injector with hollow needle & plunger) used Again surgery done to discontinue treatment, tissue toxicity at site of implant can occur. E.g., Growth hormones administered in animals through ear . TABLETS ADMINISTERED BY OTHER ROUTE

15. VAGINAL TABLET E.G. CLOTRIMAZOLE TABLET Slow drug release in vaginal cavity ovoid or peared shaped Used to release antibacterial, antiseptic or astringent to treat vaginal infections or to release steroids. Tablets are buffered to promote pH favorable action of antiseptic agent vehicles same as for buccal or sublingual tab. Drug should be compatible with plastic tube inserter used to place tab. in vaginal cavity. TABLETS ADMINISTERED BY OTHER ROUTE

16. EFFERVESCENT TABLET (E.G. DISPIRIN TABLET (ASPIRIN) Intended to produce solution rapidly with simultaneous release of CO2 Tabs. prepared by compressing drug with organic acids-such as citric acid or tartaric acid & sodium bicarbonate When tab dropped in water chemical reaction occurs within a min. or less between acid & NaHCO3 to form sodium salt of acid & to produce CO2 & water pleasant flavored carbonated drink masks bitter taste of drugs. Disadvantage:- Difficult to produce chemical stable product. Specially packaged in hermetic type for. Pouches or Stack or packed in cylindric tube. New chemically stable system. TABLETS USED TO PREPARE SOLUTION

17. DISPENSING TABLET Dispensing tablets are intended to be added to given volume of water by the pharmacist or the consumer to produce a solution of given drug concentration. HYPODERMIC TABLET One or more drugs with readily soluble (water) ingredients intended to be added in sterile water or water for injection. TABLET TRITURATES Are small, usually cylindrical molded compressed tablet for extemporaneous use prepared by the pharmacist. The drugs employed in such products were usually quite potent and mixed with lactose and a binder such as powdered acacia after which the mixture moistened to produce a moldable compactable mass. This mass was forced into the holes of mold board  for making tablets. TABLETS USED TO PREPARE SOLUTION