Dosage Forms PDF

DOSAGE FORMS 11.09.24 Dosage Forms Are the means by which drug molecules are delivered to sites of action within the body to produce optimum desired effects and minimum adverse effects. Why do we need dosage forms? 1. To provide safe and convenient delivery of accurate dosage Eg. ta...

DOSAGE FORMS 11.09.24 Dosage Forms Are the means by which drug molecules are delivered to sites of action within the body to produce optimum desired effects and minimum adverse effects. Why do we need dosage forms? 1. To provide safe and convenient delivery of accurate dosage Eg. tablets, capsules,syrups 2. To protect drug substances from atmospheric oxygen or moisture Eg. coated capsules, sealed ampoules 3. To protect drug substances from gastric acid after oral administration Eg. enteric coated tablets 4. To conceal bitter taste or bad odour of a drug substance Eg. capsules, coated tablets, flavoured syrups 5. To provide optional drug action from topical administration sites Eg. ointment, cream, ear & nasal preparations. 6. To provide for insertion of a drug into one of the body’s orifices Eg. rectal & vaginal suppositories 7. To provide extended drug action through controlled release mechanisms Eg. controlled release tablets, capsules 8. To provide for the placement of drugs within body tissues Eg. implants 9. To provide for optimal drug action through inhalation therapy Eg. inhalants Classification of dosage forms 1. Based on route of administration Oral Parenteral Topical Transdermal Inhaled Ophthalmic Rectal Vaginal Otic 2. Based on physical form Solid Semi-solid Liquid Gases Based on route of administration Based on physical form SOLID DOSAGE FORMS. Examples 1. Tablets Solid dosage form prepared by compression method, containing one or more medications 2. Capsules Solid unit dosage form that contain a solid, semi solid or liquid fill and a gelatin shell Hard gelatin capsules are used for dry powder ingredients Soft gelatin capsules are used for semi-solid or active ingredients that are dissolved in oil LIQUID DOSAGE FORMS. Examples 1. Oral solution Clear liquid preparation containing one or more active ingredients dissolved in a suitable vehicle 2. Oral suspension One or more active ingredients suspended in a suitable vehicle that usually sediments but is readily dispersed on shaking to give a uniform suspension 3. Syrup Concentrated aqueous solution of a sugar, usually sucrose, to which medicaments are added. Flavoured syrups are able to mask disagreeable tastes SEMI-SOLID DOSAGE FORMS. Examples 1. Ointments Semi-solid, greasy preparations for application to the skin, comprise less than 20% water 2. Gels Semi-solid, clear, transparent, non greasy preparation also applied on the skin 3. Creams Viscous semi-solid emulsions for external use, comprise more than 20% water PARENTERAL DOSAGE FORMS. Parenteral dosage forms INHALED DOSAGE FORMS. Examples 1. Inhaler Solutions, suspensions or emulsions of drugs in a mixture of inert propellants Lead to release of a dose of the medication under pressure in an aerosol dispenser in the form of droplets Commonly used in treatment of asthma 2. Nebulizer Device used to administer medication in form of a liquid mist to the airways Pumps air or oxygen through a liquid medicine to turn it into a vapor which is then inhaled by the patient RECTAL & VAGINAL DOSAGE FORMS. Examples 1. Suppository Semi solid, cone-shaped medication inserted into the rectum where it melts at body temperature 2. Enema Liquid introduced into the rectum and colon via the anus, eg for treatment of constipation (acts as a bowel stimulant) 3. Pessary Solid medicated preparation designed for insertion into the vagina where they melt or dissolve THE END.