Advances in Drug Research, Volume 21 comprises three chapters that deal with the general subject, specific therapeutic class, and chemical family of diverse drugs. The first chapter of this book discusses the absorption and distribution of drugs in the lymphatic system. A presentation of the anti-infective quinolones is provided in Chapter 2, while the design and therapeutic potential of peptides are elaborated in Chapter 3. Other topics covered include lymphotropic carriers and the lymph uptake mechanism; basis of circulation in lymphatic transport of molecules through various routes of administration; and general aspects and characteristics of quinolone antibacterial agents. The mode of action and mechanisms of resistance of quinolones; potent agonists and antagonists of peptides; and inhibitors of atrial natriuretic factor-degrading enzymes are also deliberated in this text. This publication is valuable to drug researchers and students interested in advances in drugs.