Drug Dosage Forms Lecture Notes PDF

Drug Dosage Forms: Physical Form Physical Form Liquids Semi Solids Solids Solid Powders: Solid dose formulations comprising micron-sized, finely fragmented particles. Granules: Particles in a group.(aggregated) Tablets: Medication in solid dose form. Capsules: G...

Drug Dosage Forms: Physical Form Physical Form Liquids Semi Solids Solids Solid Powders: Solid dose formulations comprising micron-sized, finely fragmented particles. Granules: Particles in a group.(aggregated) Tablets: Medication in solid dose form. Capsules: Gelatin capsules are used to encapsulate drugs. Lozenges: Sugar and gum-based solid formulations used to treat mouth and throat disorders. Suppositories: Solid dosage form carrying medication that is put into bodily cavities other than the mouth, such as the rectum, nose, or ear. Powders & Granules Powders are a collection of solid, loose, dry particles of the same or different chemical compositions having equivalent diameters less than approximately 1000 µm. Granules are preparations containing solid, dry aggregated groups of smaller powder particles, or individual larger particles that may have overall dimensions greater than 1000 µm. Powders and granules are themselves dosage forms. They can be filled into sachets and be administered as a dosage form.  Powders & Granules Cons Pros Lack of dose accuracy: Bulk doses Internal and external use 01 01 Bitter and unpleasant taste difficult to be masked 02 02 Internal: Reconstitution, effervescent External: Dusting powders, Large SA: stability may be compromised 03 03 Insufflation, dentifrices 04 Dry: Enhanced stability?! Powders & Granules Granules are most commonly used as an intermediate in the manufacture of other dosage forms. Most pharmaceutical granules have a short lifetime before being incorporated into tablets (mainly) or hard capsule dosage forms. Powders are granulated to improve the flow properties of the mix Capsules A shell that is mainly made of gelatin Have various sizes and colours Hard gelatin capsules: Can be filled with: powders, granules, pellets Two parts: body and cap Soft gelatin capsules: Composed of one single piece  Capsules Cons Pros Relatively expensive Taste and odour can be masked 01 01 Highly affected with storage conditions Relatively easy to swallow 02 02 Possible interaction with the gelatin Enhanced drug stability shell 03 03 Elegant 04 Compressed Tablets There are many shapes and types: Orally ingested Sublingual\Buccal Chewable Lozenges Effervescent Coated Tablets Sugar Film: normal, enteric  Compressed Tablets Cons Pros Special excipients and processing Relatively cheap equipment are needed 01 01 Maybe difficult to swallow according to Accurate dosing patient condition 02 02 Many factors can affect drug release Enhanced stability and absorption 03 03 Elegant 04 Transdermal Patches A medicated adhesive patch that is placed on the skin to deliver a specific dose of medication through the skin and into the bloodstream. Provides sustained delivery and a steady concentration of the drug in the blood. According to formulation: two main types: Matrix Reservoir Examples: nicotine, fentanyl, nitro-glycerine, hormones, scopolamine. Transdermal Patches Drug administration through skin avoids the pH variations seen with gastrointestinal transit. Drug reaches the systemic circulation whilst avoiding first-pass hepatic metabolism. Self- administration is possible. Drug intake can be stopped at any point by simply removing the transdermal patch. The simplified medication regimen leads to improved patient compliance Comparable characteristics with intravenous infusion avoiding the inconvenience of parenteral therapy invasiveness. Can be route of drug administration of choice in patients who are nauseated or unconscious. Suppositories Intended to be inserted in body cavities: Rectum, vagina (pessaries) or urethra (BOUGIES) The main excipient is called the suppository base, which can be: Fatty (oily): cocoa butter and WITEPSOL® Water-miscible: carbowax, PEG Water-soluble: Glycerogelatin Drugs are released from suppositories through either: Melting of the suppository base at body temperature Dissolution of the suppository base in rectal or vaginal fluids Suppositories Cons Pros Erratic, incomplete absorption Local and systemic effects 01 01 Irritation Avoid Gastric pH 02 02 Cultural sensitivity Avoid 1st pass effect 03 03 If oral route is not an option 04