ABSTRACT
Drugs are used in medicine to treat or to prevent disease. Sometimes they can be used alone, sometimes in conjunction with nonpharmacological measures. The vast majority of drugs have been developed to relieve symptoms or distress-to help people feel better; it is easy to assess their value to an individual patient, often immediately. A small number of available drugs are intended to modify the course of disease progression, to reduce or delay pathology Very few drugs indeed have the capacity to effect a cure; even antibiotics only serve to tip the balance in favor of host defense systems-although
certain chemotherapeutic agents can radically stop specific cancers in their tracks. The value of these drugs to an individual must be made early on clinical evidence of a response so that, if they fail, other alternatives can be tried. In most cases with drugs effective in changing the course of a disease progression, a symptomatic improvement also takes place.
