route of drug administration (pharmaceutics)

ppt

1. Route of drug administrations By Dr. Muhannad Al Rabaty MS.c pharmaceutics Course name: Pharmaceutics 1 st semester-2 nd theoretical lecture

2. CHANNELS OF DRUG ADMINI S T R A T I ON ENTE R AL P ARENTERAL TOPICAL

3. Outlines

4. Objectives

5. S Y S TEM I C Enteral Oral Rectal LOCAL Skin topical Intranasal Ocular drops Mu cosa l - t h r oa t , vagina, mouth, ear Inhalational T r ansder m al CLASSIFICATION Parenteral I n halat ional Injections Transdermal Intravenous Intr a m uscul a r Subcut a neous Intra-arterial Intr a -ar t i c ul a r Intrathecal Intradermal

6. Systemic Routes : The drugs administered through systemic routes are intended to enter blood circulation & distribute to the body & target site. Examples: Oral tablet, capsules, suspensions, injections, etc Local Routes : The drugs administered through local routes act locally to the applied areas without exposing to the other parts of the body. Examples: topical ointment, lotion, cream, spray, drops, suppositories, etc .

7. Oral or Enteral Route Drugs are administered through the alimentary tract (Enteron) known as Oral route. This is the most common route of administration . Oral refers to two methods of administration: 🞑 applying topically to the mouth 🞑 swallowing for absorption along the gastrointestinal (GI) tract into systemic circulation

8. Advantages 8 Generally safest route of administration. Convenient for patient. Economical Systemic distribution No need for sterile equipment Self-medication is easy

9. Disadvantages Slow absorption slow action Irritable and unpalatable drugs Poor bioavailability due to poor absorption First-pass effect Food–Drug interactions and Drug-Drug interactions I rritation to gastric mucosa - nausea and vomiting D estruction of drugs by gastric acid and digestive juices

10. Oral Dosage Forms Common dose forms for oral administration -Solid oral dosage forms Powders granules tablets capsules - liquid oral dosage forms solutions suspensions syrups elixirs

11. Tablet dosage form Tablet is defined as a compressed solid dosage form containing medicaments with or without excipients. 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. It is the most popular dosage form and 70% of the total medicines are dispensed in the form of Tablet.

12. Ingested tablets are as follows Ordinary tablet : These are uncoated tablets made by compression of granules. These provides rapid disintegration and drug release. e.g. Paracetamol tablet. Multiple compressed tablet Sustained action tablet Enteric coated tablet: These tablets are coated with the material which does not disintegrate in stomach but passes These tablets dissolve in intestine and are site specific. Sugar coated tablet: The compressed tablets with sugar coating are called sugar coated tablets. It is done to mask the bitter and unpleasant taste and odour of the medicament. Film coated tablet: aid in easy swallowing Chewable tablet: These tablets are chewed in mouth and are broken into small pieces. Types of tablet

13. Tablets applied in oral cavity Buccal Tablets: These tablets are to be placed in buccal pouch or between the gum & lip or cheek. Tablet dissolve & disintegrated slowly & absorb directly. Sublingual Tablet: These tablets are to be placed under the longue. They dissolve & disintegrated quickly & absorbed directly without passing into G.I.T.

14. Orodispersible tablet Lozenge tablet & troches: These tablets are designed to exert a local effect on mouth or throat. Oral thin films

15. Effervescent tablets Effervescent tablets are designed to release carbon dioxide upon contact with water, promoting their disintegration. Within a couple of minutes the tablets completely dissolve and the drug becomes available in solution. The generation of carbon dioxide is a result of the chemical reaction that occurs between a carbonate or  bicarbonate  salt (e.g., sodium bicarbonate) and a weak  organic acid  (e.g., citric or tartaric acid) in the presence of water.

16. ADVANTAGES & DISADVANTAGES Of Tablet Advantages : Easy to administered. Easy to dispense. More stable. Accuracy in dose. Bitter and nauseous substance can be easily dispensed. Light and compact. Economical .

17. Disadvantages : Hygroscopic drugs are not suitable for compressed tablets. Drugs with low or poor water solubility, slow dissolution, may be difficult to formulate. Swallowing is difficult especially for children and ill (unconscious) patients.

18. EXCIPIENTS USED IN TABLET FORMULATION Diluents: The diluent is filler needed to increase the bulk when quantity of medicament is very small in each tablet. e.g. Lactose , starch etc. Disintegrating agents : To break the tablet in smaller particles when swallowed. Glidants : To improve the flow properties of granules. e.g magnesium stearate &Talc

19. Lubricants : To reduce the interparticular friction during compression and between tablet and die wall during ejection of tablet. e.g. Talc & magnesium stearate. Binding agents: these provides strength to the granules to keep the tablet intact . e.g . gum tragacanth, methyl cellulose etc . Colors, flavors and sweetening agents

20. TABLET COATING Reasons for coating : To mask unpleasant taste and odor. To improve the appearance of tablets. To prevent the medicament from atmospheric effects. To control the site of action of drugs. To produce the sustained release product . Methods of tablet coating Sugar coating: Film coating Enteric coating.

21. ENTERIC COATING Enteric Coated tablet: These tablets are coated with the material which does not disintegrate in stomach but passes through as it is i.e. enteric polymer e.g.: Hydroxypropyl methyl cellulose phthalate etc. These tablets dissolve in intestine. These are site specific. Enteric coating is given to the tablets when: Medicaments produce severe irritation in stomach. Action required in intestine. Medicament may decompose or destroyed by stomach pH. Drug absorption is better in intestine. Delayed action is needed.

22. Evaluation tests of tablets Size and shape and appearance of tablet. Content of active ingredient. Uniformity of weight/weight variation test Uniformity of content Disintegration. Dissolution . Hardness test. Friability