Chemoprophylaxis
Encyclopedia
Chemoprophylaxis refers to the administration of a medication
for the purpose of preventing disease
or infection
. Antibiotics, for example, may be administered to patients with disorders of immune system
function to prevent bacterial infection
s (particularly opportunistic infection
). Antibiotics may also be administered to healthy individuals to limit the spread of an epidemic
, or to patients who have repeated infections (such as urinary tract infection
s) to prevent recurrence.
In some cases, chemoprophylaxis is initiated to prevent the spread of an existing infection in an individual to a new organ system, as when intrathecal
chemotherapy
is administered in patients with malignancy to prevent further infection.
The use of chemoprophylaxis is limited primarily by two factors: risk and financial costs.
has proven to be effective. In familial adenomatous polyposis
physicians observed polyps regression with NSAIDs for anti-inflammatory therapy. Chemoprophylaxis is also used to treat several different varieties of meningococcal infections for close contact exposure to Neisseria meningititis.
Medication
A pharmaceutical drug, also referred to as medicine, medication or medicament, can be loosely defined as any chemical substance intended for use in the medical diagnosis, cure, treatment, or prevention of disease.- Classification :...
for the purpose of preventing disease
Disease
A disease is an abnormal condition affecting the body of an organism. It is often construed to be a medical condition associated with specific symptoms and signs. It may be caused by external factors, such as infectious disease, or it may be caused by internal dysfunctions, such as autoimmune...
or infection
Infection
An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
. Antibiotics, for example, may be administered to patients with disorders of immune system
Immune system
An immune system is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own...
function to prevent bacterial infection
Infection
An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
s (particularly opportunistic infection
Opportunistic infection
An opportunistic infection is an infection caused by pathogens, particularly opportunistic pathogens—those that take advantage of certain situations—such as bacterial, viral, fungal or protozoan infections that usually do not cause disease in a healthy host, one with a healthy immune system...
). Antibiotics may also be administered to healthy individuals to limit the spread of an epidemic
Epidemic
In epidemiology, an epidemic , occurs when new cases of a certain disease, in a given human population, and during a given period, substantially exceed what is expected based on recent experience...
, or to patients who have repeated infections (such as urinary tract infection
Urinary tract infection
A urinary tract infection is a bacterial infection that affects any part of the urinary tract. Symptoms include frequent feeling and/or need to urinate, pain during urination, and cloudy urine. The main causal agent is Escherichia coli...
s) to prevent recurrence.
In some cases, chemoprophylaxis is initiated to prevent the spread of an existing infection in an individual to a new organ system, as when intrathecal
Intrathecal
Intrathecal is an adjective that refers to something introduced into or occurring in the space under the arachnoid membrane of the brain or spinal cord...
chemotherapy
Chemotherapy
Chemotherapy is the treatment of cancer with an antineoplastic drug or with a combination of such drugs into a standardized treatment regimen....
is administered in patients with malignancy to prevent further infection.
The use of chemoprophylaxis is limited primarily by two factors: risk and financial costs.
- All medications have the potential to cause side effectsAdverse drug reactionAn adverse drug reaction is an expression that describes harm associated with the use of given medications at a normal dosage. ADRs may occur following a single dose or prolonged administration of a drug or result from the combination of two or more drugs...
. 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 incidenceIncidence (epidemiology)Incidence is a measure of the risk of developing some new condition within a specified period of time. Although sometimes loosely expressed simply as the number of new cases during some time period, it is better expressed as a proportion or a rate with a denominator.Incidence proportion is the...
of the target disease is low. Many forms of chemoprophylaxis are therefore not cost-effectiveCost-effectivenessCost-effectiveness analysis is a form of economic analysis that compares the relative costs and outcomes of two or more courses of action. Cost-effectiveness analysis is distinct from cost-benefit analysis, which assigns a monetary value to the measure of effect...
.
Specific diseases
Using chemoprophylaxis as a treatment against early signs of tuberculosisTuberculosis
Tuberculosis, MTB, or TB is a common, and in many cases lethal, infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis. Tuberculosis usually attacks the lungs but can also affect other parts of the body...
has proven to be effective. In familial adenomatous polyposis
Familial adenomatous polyposis
Familial adenomatous polyposis is an inherited condition in which numerous polyps form mainly in the epithelium of the large intestine. While these polyps start out benign, malignant transformation into colon cancer occurs when not treated....
physicians observed polyps regression with NSAIDs for anti-inflammatory therapy. Chemoprophylaxis is also used to treat several different varieties of meningococcal infections for close contact exposure to Neisseria meningititis.
See also
- Prophylaxis, a more general term.
- Primary prevention, in which measures are undertaken to prevent the onset of disease in individuals who are susceptible (as when patients receive aspirinAspirinAspirin , also known as acetylsalicylic acid , is a salicylate drug, often used as an analgesic to relieve minor aches and pains, as an antipyretic to reduce fever, and as an anti-inflammatory medication. It was discovered by Arthur Eichengrun, a chemist with the German company Bayer...
or statinStatinStatins are a class of drugs used to lower cholesterol levels by inhibiting the enzyme HMG-CoA reductase, which plays a central role in the production of cholesterol in the liver. Increased cholesterol levels have been associated with cardiovascular diseases, and statins are therefore used in the...
s to delay the development of coronary artery disease).