The words care, therapy, treatment, and intervention overlap in a semantic field, and thus they can be synonymous depending on context. Moving rightward through that order, the connotative level of holism decreases and the level of specificity (to concrete instances) increases. Thus, in health care contexts (where its senses are always noncount), the word care tends to imply a broad idea of everything done to protect or improve someone's health (for example, as in the terms preventive care and primary care, which connote ongoing action), although it sometimes implies a narrower idea (for example, in the simplest cases of wound care or postanesthesia care, a few particular steps are sufficient, and the patient's interaction with that provider is soon finished). In contrast, the word intervention tends to be specific and concrete, and thus the word is often countable; for example, one instance of cardiac catheterization is one intervention performed, and coronary care (noncount) can require a series of interventions (count). At the extreme, the piling on of such countable interventions amounts to interventionism, a flawed model of care lacking holistic circumspection—merely treating discrete problems (in billable increments) rather than maintaining health. Therapy and treatment, in the middle of the semantic field, can connote either the holism of care or the discreteness of intervention, with context conveying the intent in each use. Accordingly, they can be used in both noncount and count senses (for example, therapy for chronic kidney disease can involve several dialysis treatments per week).
The words aceology and iamatology are obscure and obsolete synonyms referring to the study of therapies.
Levels of care classify health care into categories of chronology, priority, or intensity, as follows:
Treatment decisions often follow formal or informal algorithmic guidelines. Treatment options can often be ranked or prioritized into lines of therapy: first-line therapy, second-line therapy, third-line therapy, and so on. First-line therapy (sometimes called induction therapy, primary therapy, or front-line therapy) is the first therapy that will be tried. Its priority over other options is usually either: (1) formally recommended on the basis of clinical trial evidence for its best-available combination of efficacy, safety, and tolerability or (2) chosen based on the clinical experience of the physician. If a first-line therapy either fails to resolve the issue or produces intolerable side effects, additional (second-line) therapies may be substituted or added to the treatment regimen, followed by third-line therapies, and so on.
An example of a context in which the formalization of treatment algorithms and the ranking of lines of therapy is very extensive is chemotherapy regimens. Because of the great difficulty in successfully treating some forms of cancer, one line after another may be tried. In oncology the count of therapy lines may reach 10 or even 20.
Often multiple therapies may be tried simultaneously (combination therapy or polytherapy). Thus combination chemotherapy is also called polychemotherapy, whereas chemotherapy with one agent at a time is called single-agent therapy or monotherapy.
Adjuvant therapy is therapy given in addition to the primary, main, or initial treatment, but simultaneously (as opposed to second-line therapy). Neoadjuvant therapy is therapy that is begun before the main therapy. Thus one can consider surgical excision of a tumor as the first-line therapy for a certain type and stage of cancer even though radiotherapy is used before it; the radiotherapy is neoadjuvant (chronologically first but not primary in the sense of the main event). Premedication is conceptually not far from this, but the words are not interchangeable; cytotoxic drugs to put a tumor "on the ropes" before surgery delivers the "knockout punch" are called neoadjuvant chemotherapy, not premedication, whereas things like anesthetics or prophylactic antibiotics before dental surgery are called premedication.
Step therapy or stepladder therapy is a specific type of prioritization by lines of therapy. It is controversial in American health care because unlike conventional decision-making about what constitutes first-line, second-line, and third-line therapy, which in the U.S. reflects safety and efficacy first and cost only according to the patient's wishes, step therapy attempts to mix cost containment by someone other than the patient (third-party payers) into the algorithm. Therapy freedom and the negotiation between individual and group rights are involved.
|abortive therapy||A therapy that is intended to stop a medical condition from progressing any further. A medication taken at the earliest signs of a disease, such as an analgesic taken at the very first symptoms of a migraine headache to prevent it from getting worse, is an abortive therapy. Compare abortifacients, which abort a pregnancy.|
|bridge therapy||A therapy that figuratively provides a bridge to another step or phase, crossing over some immediate chasm (challenge), in contrast with destination therapy, which is the final therapy in cases where clinically appropriate.|
|consolidation therapy||A therapy given to consolidate the gains from induction therapy. In cancer, this means chasing after any malignant cells that may be left.|
|curative therapy||A therapy with curative intent, that is, one that seeks to cure the root cause of a disorder. (also called etiotropic therapy)|
|definitive therapy||A therapy that may be final, superior to others, curative, or all of those.|
|destination therapy||A therapy that is the final destination rather than a bridge to another therapy. Usually refers to ventricular assist devices to keep the existing heart going, not just until heart transplantation can occur, but for the rest of the patient's life expectancy.|
|empiric therapy||A therapy given on an empiric basis; that is, one given according to a clinician's educated guess despite uncertainty about the illness's causative factors. For example, empiric antibiotic therapy administers a broad-spectrum antibiotic immediately on the basis of a good chance (given the history, physical examination findings, and risk factors present) that the illness is bacterial and will respond to that drug (even though the bacterial species or variant is not yet known).|
|gold standard therapy||A therapy that is definitive, just as a gold standard diagnostic test is a definitive test.|
|investigational therapy||An experimental therapy. Use of experimental therapies must be ethically justified, because by definition they raise the question of standard of care. Physicians have autonomy to provide empirical care (such as off-label care) according to their experience and clinical judgment, but the autonomy has limits that preclude quackery. Thus it may be necessary to design a clinical trial around the new therapy and to use the therapy only per a formal protocol. Sometimes shorthand phrases such as "treated on protocol" imply not just "treated according to a plan" but specifically "treated with investigational therapy".|
|maintenance therapy||A therapy taken during disease remission to prevent relapse.|
|palliative therapy||See supportive therapy for connotative distinctions.|
| preventive therapy
|A therapy that is intended to prevent a medical condition from occurring (also called prophylaxis). For example, many vaccines prevent infectious diseases.|
|salvage therapy (rescue therapy)||A therapy tried after others have failed; it may be a "last-line" therapy.|
|stepdown therapy||Therapy that tapers the dosage gradually rather than abruptly cutting it off. For example, a switch from intravenous to oral antibiotics as an infection is brought under control steps down the intensity of therapy.|
|supportive therapy||A therapy that does not treat or improve the underlying condition, but instead increases the patient's comfort, also called symptomatic treatment (see there for more information). For example, supportive care for flu, colds, or gastrointestinal upset can include rest, fluids, and over the counter pain relievers; those things don't treat the cause, but they treat the symptoms and thus provide relief. Supportive therapy may be palliative therapy (palliative care). The two terms are sometimes synonymous, but palliative care often specifically refers to serious illness and end-of-life care. Therapy may be categorized as having curative intent (when it is possible to eliminate the disease) or palliative intent (when eliminating the disease is impossible and the focus shifts to minimizing the distress that it causes). The two are often contradistinguished (mutually exclusive) in some contexts (such as the management of some cancers), but they are not inherently mutually exclusive; often a therapy can be both curative and palliative simultaneously. Supportive psychotherapy aims to support the patient by alleviating the worst of the symptoms, with the expectation that definitive therapy can follow later if possible.|
|systemic therapy||A therapy that is systemic. In the physiological sense, this means affecting the whole body (rather than being local or locoregional), whether via systemic administration, systemic effect, or both. Systemic therapy in the psychotherapeutic sense seeks to address people not only on the individual level but also as people in relationships, dealing with the interactions of groups.|
Treatments can be classified according to the method of treatment: