The document discusses various routes of drug administration including enteral (oral, buccal, rectal) and parenteral (injections like IV, IM, SC; topical, inhalation) routes. It provides details on factors affecting absorption for different routes like buccal/sublingual, rectal, intravenous, subcutaneous, intramuscular, inhalation, nasal and topical administration. Advantages and disadvantages of each route are highlighted with examples.

1. Routes of Drug Administration Presented by: Marcia Williams

9. Isosorbide concentrations after a 5 mg oral or sublingual dose. Data from: Assinder et al. J Pharm Sci 66:775, 1977.

10. Effect of buffer pH on the buccal absorption of nicotine Adapted from: Svensson CK. Clin Pharmacokinet 12:30, 1987.

12. Availability (%) of lidocaine after IV, oral and rectal administration Data from: de Boer et al. Clin Pharmacol Ther 26:701-709, 1979. Subject IV 1 100 2 100 3 100 4 100 5 100 6 100 100 Oral 17 49 53 13 35 37 34 Rectal 59 87 80 31 100 59 71

17. While it is generally viewed that 100% of drug administered intravenously is bioavailable, prodrug administration via this route may result in less than 100% bioavailability . Drug Bioavailability Chloramphenicol succinate ~70% Dexamethasone phosphate ~90% Dexamethasone sulfate ~40% Prednisolone phosphate ~90% Prednisolone phthalate ~50% Comparative bioavailability of IV chloramphenicol succinate and oral chloramphencol palmitate IV PO Mean C90-min (mg/L) 22.6 27.5 Mean AUC (mg/hr/L) 78 110

23. Sites for SC injection

24. Disappearance of I 125 -insulin from subcutaneous injection at different sites. Data from Koivisto & Felig, Ann Intern Med 92:59, 1980 .

25. Disappearance of I 125 -insulin from subcutaneous injection at different sites. Data from Koivisto & Felig, Ann Intern Med 92:59, 1980.

28. Injection site deltoid vastus lateralis gluteus maximus Males 11.7 9.8 11.1 Females 10.2 9.4 4.3 Data from: Vukovich et al. Clin Pharmacol Ther 18:215, 1975. Peak plasma cephradine concentrations (mcg/mL) after IM administration to different sites in male and female subjects

31. Mucosal Atomizer Device From: www.ofmaa.org Intranasal naloxone administration in the field by paramedics

33. Figure from: http://www.drugdeliverytech.com/cgi-bin/articles.cgi?idArticle=61 Nasal to brain delivery of drugs