Prodrugs and Parenteral Drug Delivery

Abstract

Parenteral or injectable drug dosing is the desired route of drug administration under a number of clinical circumstances. In some countries, such as Italy, patients often prefer this route to oral dosing, while in countries like the USA the parenteral drug market is more limited. The most obvious reasons for a parenteral dosage form are when a drug cannot be taken orally due to oral absorption limitations, e.g., insulin for the treatment of diabetes, or when the patient cannot swallow oral medication, e.g., a comatose patient. Additionally, if the drug is orally toxic, as are some anticancer drugs, or immediate action is required, for example, acute life-saving treatment in an emergency room for conditions like a heart attack or an anaphylactic reaction, then injectable dosage forms are essential. For some drugs, a single sustained release intramuscular (IM) injectable dosage resulting in once a month dosing might be desired for patient convenience or for those patients known to be non-compliant.