The mechanism of action of drugs is traditionally considered the specific action of the main active ingredients. Therefore, to study the mechanism of action of drugs, specialists use selected chemical compounds in chemically pure form. However, at the beginning of the 21st century, studies have reported that the action of drugs in dosage forms (tablets, solutions, etc.) is different from the action of chemically pure ingredients. The fact is that tablets, solutions, and other dosage forms contain not only the main ingredients but also auxiliary, shape-forming ingredients, and gases that supplement the specific action of the main ingredients with their nonspecific action. The gases penetrate the dosage forms from the air; however, selected gases can be introduced into the drugs under excessive pressure. Evidence presents that purposefully altering the gas content of drug tablets and solutions can regulate their mass, volume, specific gravity, porosity, physicochemical activity, and local pharmacokinetics and pharmacodynamics, especially when drugs are administered locally. Examples are shown on how the use of this regularity has allowed the development of a new generation of drugs in Russia, namely, drugs with a specific gas composition. Studies have reported that changing the gas composition of old (registered) drugs may turn them into new drugs. Some drugs invented in Russia included gases in their formulation, which play the role of auxiliary, shape-forming, and even main ingredients. Thus, the gas composition of drugs was proposed as an additional indicator of their quality and an important factor in their physicochemical activity. An expanded list of new generation drugs was hoped for in the near future.