Pleiotropy (drugs) can respond to them, because the endogenous ones are endocrine messengers. Pleiotropy (drugs) In pharmacology, pleiotropy includes all of a drug's actions other than those for which the agent was specifically developed. It may include adverse effects which are detrimental ones, but is often used to denote additional beneficial effects. For example, statins are HMG-CoA reductase inhibitors that primarily act by decreasing cholesterol synthesis, but which are believed to have other beneficial effects, including acting as antioxidants and stabilizing atherosclerotic plaques. Steroid drugs, such as prednisone and prednisolone, have pleiotropic effects, including systemic ones, for the same reason that endogenous
Reference ranges for blood tests range for a blood test is generally the venous range, as the standard process of obtaining a sample is by venipuncture. An exception is for acid-base and blood gases, which are generally given for arterial blood. Still, the blood values are approximately equal between the arterial and venous sides for most substances, with the exception of acid-base, blood gases and drugs (used in therapeutic drug monitoring (TDM) assays). Arterial levels for drugs are generally higher than venous levels because of extraction while passing through tissues. Reference ranges are usually given as what are the usual (or "normal") values found in