In some cases, chemoprophylaxis is initiated to prevent the spread of an existing disease in an individual to a new organ system, as when intrathecal chemotherapy is administered in patients with malignancy to prevent brain metastasis.
A related term is primary prevention, in which measures are undertaken to prevent the onset of disease in individuals who are susceptible (as when patients receive aspirin or statins to delay the development of coronary artery disease).
The use of chemoprophylaxis is limited primarily by two factors:
- All medications have the potential to cause side effects. In general, chemoprophylaxis should be initiated only when the benefits of treatment outweigh the risks.
- The cost associated with chemoprophylaxis may be prohibitive, particularly when the cost of treatment is high or the incidence of the target disease is low. Many forms of chemoprophylaxis are therefore not cost-effective.
Chemoprophylaxis is also used to treat several different varieties of meningococcal infections for close contact exposure to Neisseria menigitidis.