Parenteral formulation injectable medication

Reports of macrolides causing adverse reactions in humans relate primarily to medicated stockfeed and parenteral formulations for injection. Farmworkers exposed to stockfeed medicated with spiramycin and tylosin have developed dermatitis and bronchial asthma. In addition, accidental needlesticks with needles contaminated with tilmicosin have caused minor local reactions, whereas accidental self-administration of injectable formulations of tilmicosin has resulted in serious cardiac effects and death. 

Many drugs are administered as parenterals for speed of action because the patient is unable to take oral medication or because the drug is a macromolecule such as a protein that is unable to be orally absorbed intact due to stability and permeability issues. The U.S. Pharmacopoeia defines parenteral articles as preparations intended for injection through the skin or other external boundary tissue, rather than through the alimentary canal. They include intravenous, intramuscular, or subcutaneous injections. Intravenous injections are classified as small volume (<100 mL per container) or large volume (>100 mL per container) injections. The majority of parenteral dosage forms are supplied as ready-to-use solutions or reconstituted into solutions prior to administration. Suspension formulations may also be used,101 although their use is more limited to a subcutaneous (i.e., Novolin Penfill NOVO Nordisk) or intramuscular (i.e., Sandostatin LAR Depot Novartis) injection. Intravenous use of disperse systems is possible but limited (i.e., Doxil Injection Ortho Biotec). 

Many drugs can now be delivered rectally instead of by parenteral injection (intravenous route) or oral administration. Generally, the rectal delivery route is particularly suitable for pediatric and elderly patients who experience difficulty ingesting medication or who are unconscious. However, rectal bioavailabilities tend to be lower than the corresponding values of oral administration. The nature of the drug formulation has been shown to be an essential determinant of the rectal absorption profiles. The development of novel absorption enhancers with potential efficacy without mucosal irritation (low toxicity) is very important. The delivery of peptide and protein drugs by the rectal route is currently being explored and seems to be feasible. 

Chitosan was also formulated in a controlled-release protein delivery system using bovine serum albumin (BSA) as a model drug. Chitosan was reacted with sodium alginate in the presence of tripolyphosphate for bead formation [94]. Parenteral administration of proteins/peptides requires repeated injections because of their extremely short biological half-life. Daily multiple injections are highly risky and require close medical supervision. On this basis, bovine serum albumin (BSA)-loaded chitosan microspheres were prepared to test the drug release behavior in buffers with different pH values. BSA-chitosan microspheres with particle sizes in the range from 5 to 10 pm... 

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